Carbon Steel Key-Locking Inserts (AKA Keenserts®) at www.mfsupply.com

MF Supply is an expert and industry leader when it comes to key-locking inserts, commonly known by the popular brand name Keensert®. We stock and source key-locking inserts in a wide variety of materials, platings and sizes, including Inch, Metric, Commercial and Mil-Spec options.

In today’s blog, we will showcase a comprehensive overview of Carbon Steel Key-Locking Inserts, covering their benefits, uses, styles, standards, sizes, and comparison with other key-locking inserts made from other materials — so you are all set before jumping off to procure them for your next project.

What are Carbon Steel Key-Locking Inserts?

Carbon Steel Key-Locking Inserts, often referred to in industry vernacular as Carbon Steel Keenserts®, are precision-engineered threaded inserts predominantly fabricated from high-grade carbon steel.

Featuring both internal and external threads, these inserts are adept at providing wear-resistant thread interfaces in substrates that are inherently susceptible to thread degradation or are insufficiently robust for the intended mechanical loads. The external threading of these inserts exhibits a larger diameter and pitch compared to the internal threads, ensuring a secure engagement with the parent material.

These components are specifically designed for thread reinforcement and repair applications across a broad spectrum of parent materials. Their key-locking mechanism involves the deployment of keys integrated into the insert body. Upon installation into a pre-tapped hole, these keys are driven outward into the parent material, thereby affording a secure mechanical lock that resists rotational and axial forces. Hence, this feature is pivotal in applications where vibrational loads or cyclic stresses are prevalent.

The versatility of Carbon Steel Key-Locking Inserts makes them beneficial for any sector requiring durable, reliable threaded connections, especially where materials are subject to wear, high stress, or require thread repair and reinforcement.

Carbon Steel Keenserts®, or Key-Locking Inserts, have different styles in order to cater to a wide range of application requirements and material conditions. The distinct styles are designed to address specific challenges such as load capacity, space constraints, installation requirements, and the physical properties of the base material. Below is a list of all the styles available for these Key-Locking Inserts:

  • Thin Wall | RKKA | KNM: These are used when minimal space is available or in applications where less material needs to be removed. They offer a good balance between strength and size. Available off the shelf in Internal Thread 10-24 through 1/2-20 and Metric M5-M12. Often referred to by their original Fairchild part numbers: RKKA
  • Heavy Duty | RKK | KNHM: Designed for higher strength and durability, these are suitable for applications subject to high stress or where a stronger thread is required. Available off the shelf in Internal Thread 8-32 through 1-1/2, and Metric M4-M24. Often referred to by their original Fairchild part numbers: RKK
  • Extra Heavy Duty | KNHXH: These inserts are used in extremely demanding applications where very high pull-out and torque resistance is needed. Available off the shelf in Internal Thread 6-32 through 1-12. No standard Metric option available. Often referred to by their original Fairchild part numbers: KNHXH
  • Solid | KNJ: Unlike other types have both internal and external thread, solid inserts have only external thread. Once installed, they can be drilled and tapped as required. These solid inserts can be used to relocate misplaced holes, customize the internal threads, or plug existing holes.  They are extremely durable but might require more installation space. Available off the shelf in External Thread 3/8-16 through 1-1/4 and Metric M8-M32. Often referred to by their original Fairchild part numbers: KNJ.

Commonly available in diameters from 6-32 through 1-1/2, Carbon Steel Key-Locking Inserts can be used in a wide range of applications from small electronics to heavy machinery. The thread pitch varies accordingly, with finer pitches for delicate applications and coarser pitches for heavy-duty applications.

Carbon Steel Key-locking inserts are generally offered as commercial parts, and don’t have a Mil-Spec equivalent. They come standard with a phosphate finish.

*Note – Carbon Steel Key-locking Inserts do not come with a Self-Locking option, which is a standard option with Stainless Steel Keenserts®.

The Carbon Steel Difference!

How do Carbon Steel Key-Locking Inserts stack up against other materials? Here’s the breakdown:

  • Stainless Steel: Stainless Steel Keenserts® are known for their corrosion resistance, especially in marine and chemical environments. However, Carbon Steel Key-Locking Inserts are generally stronger and more wear-resistant, which is beneficial in applications where the primary concern is strength rather than exposure to corrosive elements.
  • 4140 Alloy Steel: This is a high-carbon alloy steel that provides excellent wear resistance and strength. While 440 Alloy Steel Keenserts® offer superior hardness, Carbon Steel Key-Locking Inserts typically excel in toughness and are more ductile, making them less likely to crack under high stress.
  • A286: A286 is an iron-nickel-chromium stainless steel alloy known for its high strength and corrosion resistance at elevated temperatures. Carbon Steel Key-Locking Inserts may not match the high-temperature performance but are significantly more cost-effective for applications where extreme temperatures are not a concern.
  • Nitronic 60: This material provides excellent galling and wear resistance. While it is superior in environments where these factors are critical, Carbon Steel Key-Locking Inserts offer a better balance of strength and cost-efficiency for general-purpose use.
  • Inconel: Known for its ability to withstand extreme temperatures and corrosion, Inconel is often used in high-temperature applications. Carbon Steel Key-Locking Inserts, on the other hand, are more widely used in applications where high temperature and corrosion are not as critical but where high strength and lower cost are important.

Hence, Carbon Steel Key-Locking Inserts offer an excellent balance of performance and value, making them a preferred choice for applications where the benefits of higher-cost, specialized materials are not required. They stand out for their strength, toughness, and cost-effectiveness, providing a reliable and affordable solution for thread reinforcement and repair.

Carbon Steel Key-Locking Inserts at MF Supply!

MF Supply is a WBE/WOSB certified business, and a leading supplier of Carbon Steel Key-locking Inserts (AKA Keenserts®) for manufacturers, government and industry. At MF Supply, we understand the dynamic needs of the industry, including the balance of price, quality, availability and certification paperwork. Ready to see how we can help you make a difference?

Visit our website or browse through the links provided below to discover the perfect Carbon Steel Key-Locking Inserts for your next project!

Inch Carbon Steel Key-locking Inserts:

Metric Carbon Steel Key-locking Inserts:

Note – Installation requires a drill bit, a standard tap, an installation tool, and a hammer. Feel free to ask us about Keensert® Kits available for many Carbon Steel sizes. Kits include a minimum of 2 inserts, a drill bit, a tap and an installation tool.

Do you still have questions or would like to speak with a representative? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “The right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Creatively Solve Problems – We are sourcing experts and specialize in hard to find parts. We offer custom manufacturing and reworking solutions at competitive pricing, reducing long deliveries.
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies, with an expertise in inserts, military fasteners and stainless steel hardware.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


Domestic Socket Products at www.mfsupply.com!

Greetings to our precision manufacturing community!

We are reaching out with an important announcement regarding our domestic sockets product lines. As we continuously strive to bring you the best in quality and service, we want to inform you of a significant change in our offerings.

Firstly, we want to address a key change: the Blue Devil® brand, a name many of you have come to trust and rely on for your domestic socket products needs, will no longer be produced. This marks the end of an era, but also the beginning of an exciting new chapter.

We are thrilled to introduce American Sockets – a new brand of domestic socket products! This transition is more than just a change in name; it’s a reaffirmation of our continued commitment to quality and excellence.

  • Continuity in Quality and Manufacturing: While the brand name changes, what remains constant is the quality of the products. American Sockets are manufactured by the same esteemed US manufacturers that produced the majority of the Blue Devil products. This ensures that the products you’ve trusted for years will continue to be of the same high standards.
  • Seamless Transition: We understand the importance of consistency in your operations. Rest assured, that this transition from Blue Devil to American Sockets will be seamless, with no compromise in the product quality or variety that you have come to expect.

MF Supply is a WBE/WOSB woman owned business, and leading supplier of Domestic Socket Products including major OEM brands, such as American Sockets, and brand equivalents, in various sizes and materials. We offer options when it comes to made in the USA, DFAR compliant Socket Products. Many of our products are available with Certificate of Conformance and full certifications available upon request.

Here are links to the American Socket brand of Inch Domestic Socket Product Lines:

Here are links to the American Socket brand Metric Domestic Socket Product Lines:

In addition to American Sockets brand Socket Products, we offer a vast choice of socket products, including Mil-Spec, OEM branded, standards and custom made specials. To search for what you need, use our Search bar, then filter by size, material, specification, or other qualities you are seeking. Alternatively, you can check out these handy links to view by category:

Do you still have questions or would like to speak with a representative? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “Finding the right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts and specialize in hard to find parts. We offer custom manufacturing and reworking solutions at competitive pricing, reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


Inch & Metric Carriage Bolts Now Available at www.mfsupply.com!

In the realm of industrial manufacturing and engineering, Carriage Bolts often go unnoticed, yet they play a pivotal role in ensuring structural integrity and reliability. This versatile fastener, commonly known for its unique design featuring a rounded head and a square shank, is a cornerstone in a myriad of applications, such as construction and industrial projects. But just like many other popular fasteners, one size isn’t the right fit for all applications, and this is also the case with Carriage Bolts. So how do you make the right choice?

In today’s blog we will enlighten you about the key aspects of Carriage Bolts, covering their unique features, standards, materials, sizes, strengths/grades, uses and anything else you should know before setting off to buy them for your next big project!

What are Carriage Bolts?

A Carriage Bolt is a type of fastener that belongs to the bolt family. It is characterized by a domed or rounded head and coupled with a square section just beneath the head. This distinctive shape allows the bolt to sit smoothly against surfaces while the square part locks into the material, preventing the bolt from rotating or turning when the nut is being tightened.

Commonly used in industrial manufacturing and construction, they are ideal for metal-to-metal or metal-to-wood connections, providing a secure and aesthetically pleasing joint. Available in various materials like carbon steel, stainless steel, and alloy steel, and conforming to specific standards like ASME 18.5, SAE J429 and DIN 603 carriage bolts come in a range of sizes and grades to suit different mechanical and environmental requirements. Their versatility and reliability make them a staple in heavy-duty applications where robust fastening is essential.

Who Uses Carriage Bolts?

The robust nature of Carriage Bolts makes them an indispensable asset in many sectors, each valuing their unique combination of strength, security, and aesthetics.

  • Construction and Building Industry: In the construction and building industry, they are essential for timber framing and outdoor decking, ensuring durability and safety.
  • Automotive and Heavy Machinery Sectors: The automotive and heavy machinery sectors rely on them for vehicle assembly and manufacturing robust equipment.
  • Marine and Coastal Applications: In marine and coastal applications, particularly, stainless steel Carriage Bolts are prized for their resistance to saltwater corrosion, vital in boat building and dock construction.
  • Railway Industry: Their use also extends to the railway industry for maintaining railway lines and infrastructure.
  • Aerospace Industry: Even in aerospace, though less common, Carriage Bolts find a place in non-critical applications, appreciated for their ease of installation and tamper-resistant design.

Whether you’re in construction, automotive manufacturing, aerospace or marine applications, Carriage Bolts play a pivotal role, underscoring their versatility and the trust placed in them by many professionals. Remember, when you’re choosing Carriage Bolts, you’re not just buying a component; you’re investing in the integrity and longevity of your entire project.

What Styles, Standards, Materials, Finishes & Sizes Are Available?

Carriage Bolts’ Styles

The world of Carriage Bolts is vast and varied, catering to a wide range of applications. Understanding this diversity is key to selecting the right bolt for your project. The traditional round head and square neck style is commonly used, but there are other types like Ribbed Neck or Knurled Neck bolts, which offer extra grip. Short Neck variants are useful in tight spaces, while Shaker Screen bolts are designed to withstand high-vibration environments. For specific fitting requirements, Under Sized Body bolts might be the solution, and Flat Head Carriage Bolts are ideal when a flush surface finish is needed. This variety demonstrates how specific designs cater to unique functional needs.

Quality Standards

Carriage Bolts are manufactured according to various quality standards, such as ASME 18.5, SAE J429, and DIN 603. These standards ensure consistency in dimensions, strength, and durability. They also play a crucial role in ensuring that carriage bolts meet the necessary safety and performance requirements across different applications. For instance, a bolt compliant with these standards would have reliable tensile strength and dimensional accuracy, making them suitable for a range of uses from construction to machinery assembly.

Materials

Different materials are used in the manufacturing of Carriage Bolts to suit various environmental and mechanical demands.

  • Low Carbon Steel Zinc: Commonly used for standard Carriage Bolts. The zinc coating provides a layer of corrosion resistance. Offers a good combination of tensile strength and ductility, making it suitable for light to medium load applications.
  • Grade 5 Steel: Contains a higher carbon content than low carbon steel, resulting in increased strength. Often used in automotive and construction applications where higher strength is needed. Provides a good balance between strength and flexibility, making it less likely to break under high stress.
  • Grade 8 Steel: Contains an even higher carbon content than Grade 5, offering superior strength and hardness. Commonly used in demanding applications like heavy machinery and military equipment. Ideal for applications where the bolt must withstand high stress or sudden impact without deforming.
  • Stainless Steel 18-8: Composed of approximately 18% chromium and 8% nickel, hence the name 18-8. Offers excellent resistance to corrosion and oxidization. Widely used in environments where exposure to water, chemicals, or saline is common.
  • Stainless Steel A2: Similar to 18-8 stainless steel but with slight variances in the alloy composition. Common in food processing equipment and outdoor furniture. Resistant to corrosion and staining, making it ideal for aesthetic applications as well.
  • Stainless Steel A4: Also known as marine grade stainless steel. Contains higher levels of nickel and added molybdenum for enhanced corrosion resistance. Ideal for use in highly corrosive environments such as marine, coastal, and tropical climates.

Finishes

The finish of a carriage bolt not only affects its appearance but also its functionality, especially in terms of corrosion resistance. Black Oxide and Black Zinc finishes offer a degree of corrosion resistance along with an aesthetically pleasing look. For environments with high moisture, Hot Dip Galvanized bolts are an excellent choice for their superior corrosion protection. Zinc-Plated and Zinc-Yellow finishes are also popular, offering a balance between corrosion resistance and affordability. Understanding these options is essential for selecting a bolt that not only fits the technical requirements but also withstands environmental conditions.

Sizes Available

The size of a carriage bolt is also another critical factor in ensuring its effectiveness in a given application. The range of sizes available is extensive, from 6-32 through 7/8-9 for inch sizes to M5-0.8 through M12-1.75 for metric DIN 603 sizes. This broad spectrum of sizes accommodates everything from large-scale industrial needs to smaller, custom projects. Selecting the appropriate size is vital for the bolt’s performance, as it affects the strength of the joint and the overall integrity of the project.

How to Order Them

On our website, navigate to the Search bar and type “Carriage Bolt,” and hit the Search Button.

Once the results are listed and the filter appears on the left of the results page, select your desired attributes to get the specific Carriage Bolt(s) you need. Common attributes available in our filters include:

  • Inch or Metric
  • Head Style
  • Size (Diameter & Thread)
  • Length
  • Material
  • Finish
  • Other Type (Full or Partial thread or Flank Degree)
  • Standard (ASME, SAE, DIN)

Carriage Bolts at MF Supply

MF Supply is a WBE/WOSB certified business, and a trusted supplier of Carriage Bolts to manufacturers, government and industry. At MF Supply, we understand the dynamic needs of the manufacturing industry, including the balance of price, quality, availability and certification paperwork. The expansion of our product catalog to include Carriage Bolts in a myriad of styles, materials, and sizes demonstrates our commitment to being a one-stop solution for all your fastener needs.

Visit our website or browse through the links provided below to discover the perfect Carriage Bolt(s) for your next project!

Do you still have questions or would like to speak with a representative? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “Finding the right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts and specialize in hard to find parts. We offer custom manufacturing and reworking solutions at competitive pricing, reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


Inch & Metric Nitronic Keenserts® Now Available at www.mfsupply.com!

In the bustling world of manufacturing and engineering, where every component counts and the margin for error is slim, MF Supply recognizes the intricacy involved in sourcing materials that offer both superior performance and extended durability. This is where our friends, the Key-locking Inserts (AKA Keenserts®) become the stars of the show. Today, we’re turning the spotlight on an insert that’s been making waves in the industry: the Nitronic 60 Key-locking Insert!

If you’re on the quest for Key-locking Inserts that promise to elevate the integrity of your projects, you’re in the right place. Nitronic 60 key-locking Inserts are not just components; they’re your peace of mind molded into high-performance alloy.

Why Nitronic 60 Key-locking Inserts? The Vanguard of Resilience

Picture a material that laughs in the face of wear, shrugs off corrosion, and doesn’t flinch under high torque. That’s Nitronic 60 for you — an alloy steel that’s as tough as they come. Crafted from this robust alloy, Nitronic Key-locking Inserts boast unparalleled wear and galling resistance. For those of you constantly battling the wear and tear that comes with mechanical demands, these threaded inserts are your knights in shining armor. Think of them as the silent guardians against the everyday wear-and-tear that can compromise your work.

The Rust Doesn’t Sleep, But You Can

Corrosion is the arch-nemesis of metal, lurking and waiting to undermine your structures. But with Nitronic 60’s exceptional corrosion resistance, rest easy knowing that your components are as steadfast as your ambition. Whether it’s the salty bath of marine environments or the demanding conditions of chemical processing, they’ve got you covered.

Strength That Speaks Volumes

Nitronic 60 Key-locking Inserts don’t just resist wear; they embrace strength. High stress, high torque — bring it on! The formidable might of Nitronic 60 makes these Key-locking Inserts the backbone for applications that can’t afford to falter, from the aerospace zeniths to the depths of automotive innovation.

The Nitronic 60 Difference

We hear you asking, “But how do they stack up against other materials?” Here’s the deal:

Nitronic 60, as a material, is a high-performance stainless steel alloy known for its excellent strength and resistance to wear and galling. This versatile alloy provides exceptional resistance to high temperature oxidation, crevice corrosion and general corrosion, making it well suited to marine and chemical applications. Key-locking inserts made from Nitronic 60 are used in various applications where high strength and corrosion resistance are a must.

  • Carbon Steel Inserts: Compared to standard steel, Nitronic 60 offers superior resistance to corrosion and galling.
  • Stainless Steel Inserts: Among stainless steels, Nitronic 60 typically outperforms varieties such as 304 or 316 in wear resistance.
  • Inconel Inserts: Inconel excels in high-temperature applications but comes at a higher cost and greater machining difficulty than Nitronic 60.
  • 4140 Alloy Inserts: 4140 Alloy provides greater tensile strength and enhanced performance at high temperatures, although it falls short in corrosion resistance and often necessitates protective coatings. Nitronic 60 is better suited for applications involving friction at moderate temperatures.
  • A286 Inserts: A286 excels in high-temperature applications, maintaining higher strength at elevated temperatures, though it’s tougher to machine and more expensive than Nitronic 60.

A Spectrum of Possibilities

We’re not about “one-size-fits-all” because we know your engineering needs are as unique as your blueprints. That’s why we offer Key-locking Inserts in inch, mil-spec and metric sizes that are tailored to the scope and scale of your vision — common internal diameters include #2-56 through 1 1/2-6 for inch & mil-spec sizes, and M2 through M24 for metric sizes. And with varying lengths at your disposal, the only limit is the application and your imagination. Materials

Compliance with stringent industry standards is not just a promise; it’s our practice. Our inserts meet or exceed critical aerospace and military specifications, ensuring that they deliver in applications where there is no room for error. Standards available include MS51830, MS51831, MS51832, NAS1394 and NAS1395. Series available include Miniature KNC, Thin Wall KN & KNM, heavy-duty KNH & KNHM, and extra heavy-duty series KNHXH.

Whether you’re in aerospace, automotive, defense, or any field that demands unyielding materials, these inserts are ready to serve. They’re the go-to for applications that require repeated assembly and disassembly, ensuring longevity and reliability every step of the way.

Discover More, Achieve More

MF Supply is a WBE/WOSB certified business, and a trusted supplier of Nitronic 60 Key-locking Inserts (AKA Keenserts®) for manufacturers, government and industry. Eager to delve deeper into the world of Nitronic 60 Key-locking Inserts? Visit our website, where innovation is just a click away, and join the ranks of manufacturers and engineers who don’t just build, but inspire.

With Nitronic 60 Key-locking Inserts, it’s not just about holding things together; it’s about unlocking possibilities. Discover the sizes, standards, and the success that our inserts can enable.

Inch & Mil-Spec Nitronic 60 Key-locking Inserts

Metric Nitronic 60 Key-locking Inserts

Do you still have questions or would like to speak with a representative? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “Finding the right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts and specialize in hard to find parts. We offer custom manufacturing and reworking solutions at competitive pricing, reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


“Heli-coils®” vs. “Keenserts®”: 3 differences you must know-Part 2 of 2

Welcome back to the second part of, “Heli-coils®” vs. “Keenserts®”: 3 differences you must know. As a refresher, both Helical Wire Inserts (AKA Heli-coils®) & Key-locking Inserts (AKA Keenserts®) are popular threaded inserts that are commonly used in precision manufacturing, transportation, and aerospace applications. Their uses overlap range from restoring/repairing stripped threaded holes, strengthening threaded holes in metals and other soft materials, providing high resistance to torque-out and pull-out, & to place threaded holes on materials too thin to accept them. The three main differences between Wire Inserts and Key-Locking Inserts lie in their strength, ease of installation & price. Today we will continue on from where we left of on our previous blog, and discuss about OEM brands, Mil-spec options, and how to order them!

Threaded Inserts’ Brands & Equivalents

A Helical Wire Insert, commonly known as “threaded wire insert,” is essentially a coil-wire made of stainless steel or other materials which, when installed, provide a new threaded hole surface. One of the most recognized brands for helical inserts is “Heli-Coil®,” but there are several others as well, including E-Z Lok, Bollhoff, Recoil, KATO, Perma-Coil, V-Coil and Time-Sert. Below is a list of some of the most well known brands for this category:

  • Heli-Coil®: Part of the Stanley Engineered Fastening brand, Heli-coil’s name is nearly synonymous with threaded wire inserts, and Heli-coil®is a registered trademark of Emhart® Teknologies, Inc.
  • Recoil®: Part of Howmet’s (previously Arconic, formerly Alcoa Fastening Systems) wire thread insert offering. Recoil offers helical wire inserts in bulk, replacement packets, kits and associated tools, taps and drill bits.
  • E-Z Lok®: Offering Wire Inserts under the E-Z Coil™ Helical Coil Insert brand, specializing in industrial and automotive .
  • KATO®: The Original Inventor & Manufacturer of the Bi-Directional Tangless Insert.

A Key-locking Threaded Insert, commonly known by the popular brand name “Keensert® and Keysert®,” is a solid bushing style threaded insert with unique external keys that get hammered into grooves through the threads—permanently locking the insert in place. Key-locking inserts are specifically designed for high-stress applications where strong, permanent threads are essential. Key-locking inserts offer exceptional resistance to vibration, torque-out and pull-out, making them suitable for critical components and assemblies that require a secure, immovable joint, or in scenarios where frequent assembly and disassembly might weaken the primary thread strength of the base material. While “Keensert®” is a trademarked name, tens of manufacturers and brands offer similar products in the solid threaded insert category including Acme, Camloc, Chrislynn, Clarendon, Fairchild, Loksert, Kaynar, Microdot and Tridair brands. Here is a list of the most popular brands:

  • Keensert®: is a registered trademark of Huck Patents, Inc. The trademark name is currently owned by the company that started it all, Howmet (formerly Arconic & Alcoa Fastening Systems).
  • Recoil®: The trademarked Keysert name belongs to Recoil, which is also part of the current Howmet family (formerly Arconic & Alcoa Fastening Systems).
  • Carr-Lane: Specializing in Tooling Components, Carr-Lane offers a large selection of Inch and Metric Key-locking inserts in steel and stainless steel.
  • Fairchild Fasteners®: Purchased by Arconic in 2002, Many original Fairchild part numbers are still produced and commonly used in the aerospace industry.
  • Acme – USA based manufacturers of inch, metric, Industrial Style and Mil-Spec key-locking inserts in a variety of materials and finishes.

Note: Various manufacturers and brands have their own designs, strengths, materials and applications for which they’re best suited. When choosing a threaded insert, it’s essential to consider factors like the material you’re working with, the stresses the insert will be under, and the expected lifecycle of the product. Industrial, automotive and aerospace industries each have their own requirements, which may include DFAR, First Article or other certifications. If you need assistance finding out what type of threaded insert is best suited for the project you’re working on, read part one of this blog, or reach out to us with your questions. MF Supply is an expert and leading supplier of Helical Wire Inserts and Key-locking Threaded Inserts—functional equivalents to top & expensive brands, such as Heli-Coil® & Keensert®.

Mil-Spec Options

Mil-spec Helical Wire Inserts (Heli-Coils®) are crafted to meet military specifications. They carry specific labels signifying their adherence to the rigorous standards established by the U.S. Department of Defense in order to guarantee that the inserts will fulfill the necessary requirements for military applications.

With that having been said, these threaded inserts often show up as free-running or self-locking inserts under their Mil-spec numbers, which can be crossed to commercial equivalents. Some common Mil-spec Helical Wire Inserts’ series include MS122076 through MS124831, MA1565, MA3276, MA3277, MA3278, MA3279, MA3280, MA3281, MA3329, MA3330, MA3331, , MS21208, MS21209, MS33537, NA0276, NAS1130

Mil-Spec key-locking threaded inserts (Keenserts®) adhere to distinct mil-spec (military specification) series. Options for these inserts include Miniature, Thinwall & Lightweight, Heavy Duty, Extra Heavy Duty, Keylocking Inserts in Stainless Steel, A286, and 4140 Alloy materials. Here are several prevalent mil-spec series associated with them: MS51830, MS51831, MS51832, NAS1394, NAS1395, NA0146, NA0147, NA0148, NA0149, NA0150, NA0151. The mil-spec parts will often have a commercial equivalent that is also known under the original Fairchild nomenclature, including the KN, KNC, KNH, KNL & KNCL Series.

Authentic Mil-spec parts will be available with documentation that confirm their compliance to the specification. Examples of certified paperwork might include a Certificate of Conformance, material traceability, DFAR statement, and chemical and/or physical tests reports.

How to Order

Now you know the differences between Helical / Heli-coils® and Key-locking / Keensert® / Keyserts®, the brands available, and the mil-spec series options.

To find the exact insert you are seeking on our website, there are currently four ways to proceed:

1. You can visit the Keenserts®, Threaded Inserts & Helical Wire Inserts category section of our website, and choose between Keenserts® for Manufacturers or Helical Wire Inserts. Once you select the desired category of products, you can then narrow down your search by selecting between metric or inch & mil-spec sizes, materials, etc.

2. You can also visit our website and enter the product standard, product number or keyword (e.g., MS51830, MS51830-101, “Keenserts,” “Helical Inserts,” etc.) in our search bar, and click the “Search” button. Once the list of available products are listed, you may use our product filters to search for the desired size, material, etc.

3. Alternatively, you could also use our newly added Product Finder tool! Select the desired Item Type, Subtype, Material, etc. And when you’re done selecting, simply click on the “Search” button, and the product finder will display a list of available products for you. 

4. Lastly, you could also reach out to us or Request a Quote. Our MF Supply team of sourcing experts are here to assist you and help you find the right product(s).

Once you find the insert you need, you can request a quote or buy online.

Key-locking Inserts (Keenserts®) & Helical Wire Inserts (Heli-Coils®) at MF Supply

MF Supply is a WBE/WOSB woman owned business, and leading supplier of Keenserts® & Helical Wire Inserts including major OEM brands and brand equivalents, in imperial, metric and mil-spec sizes and materials.

We stock a huge inventory including Miniature, Thinwall, Lightweight, Heavy Duty, Extra Heavy Duty, Locking, Non-Locking, Solid and Floating style Keenserts® in a variety of sizes and materials. Our mil-spec and certified insert products are DFAR compliant with COC and full certifications available upon request.

We Invite You To Request a QuoteDownload a Guide or a Line Card Today!

Do you still have questions or would like to speak with a representative to request a quote? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “Finding the right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts, offer competitive pricing and specialize in finding hard to find parts and reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


“Heli-coils®” vs. “Keenserts®”: 3 differences you must know-Part 1 of 2 (Refreshed for 2023)

Today we will re-introduce you to our blog, “Heli-coils®” vs. “Keenserts®”: 3 differences you must know-Part 1 of 2, published back on 2020. We will compare these two fastener products that are used to repair damaged threads & threaded holes, or to strengthen/reinforce a weaker parent material like aluminum. Both Helical Wire Inserts & Key-locking Inserts are commonly used in precision manufacturing, transportation and aerospace applications. Their versatility, however, ensures their presence in nearly every industry that utilizes threaded fasteners.

What are the main uses of Threaded inserts?

Both “Heli-coil®” or Helical wire inserts and “Keensert®” or Key-locking inserts fall under the “Threaded Insert” category of fasteners.

Threaded insert, also known as a threaded bushing, is an insert that has internal threads, and is fastened into an object to add or reinforce a threaded hole.  Threaded inserts may be used to repair a stripped threaded hole, provide a durable threaded hole in a soft material, place a thread on a material too thin to accept it, mold or cast threads into a work piece thereby eliminating a machining operation, or simplify changeover from unified to metric threads or vice versa. Although Helical Wire inserts and Key-locking externally threaded inserts are used in similar ways, there are 3 main distinctions that we detail below. But first, let’s take a closer look at each of these fasteners:

What is a Helical Insert Wire Insert? (aka Heli-coil®)

Helical wire inserts are precision-formed continuous wire coils that provide permanent, wear-resistant threads which exceed the strength of the parent material. Often underestimated, the popular misconception is that Helical wire inserts are intended solely for thread repair, when, in fact, they have other significant uses.  Not to be confused with other types of threaded inserts or rivnuts, Helical wire inserts resemble springs and are sometimes referred to as “Screw Thread Inserts (STI)” ,“Helicals” or by the popular brand “Heli-Coil®” which is a registered trademark of Emhart® Teknologies, Inc.

Three typical applications for using Helical wire inserts are:

  • to repair damaged threads in parts that would otherwise have to be scrapped
  • to strengthen threads against failures due to stripping, seizing or corrosion
  • to convert threads between inch and metric sizes

What is a Key-locking insert? (aka Keensert® or Keysert®)

The Key-locking threaded insert is a solid bushing style insert that is threaded on both the inside and the outside and has wedges or “keys” attached to the top of the insert. These externally threaded inserts are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion. Key-locking inserts are commonly used in high torque and high temperature situations, and in applications where fasteners may be repeatedly removed and reassembled. Key-locking inserts are often referred to as Keenserts® and Keyserts®, which are registered trademarks for the most popular brand names for this part. (Keensert® is a registered trademark of Huck Patents, Inc. & Keysert® is a registered trademark of Alcoa Fastening Systems).

Typical applications are transmission housings, electronic equipment and suspension units. Key-locking inserts are commonly found in aerospace assemblies.

How do they work?

Helical wire inserts work because the diamond shaped helically formed wire coil screws into a threaded hole to form a mating internal thread for a screw or stud.  

Key-locking inserts are threaded into a pre-tapped hole, and then the keys are hammered into grooves through the threads, permanently locking the insert in place. Their “keys”, which are driven down into the tapped threads, provide a mechanical lock against rotation, especially when the mating stud or bolt will be removed frequently.

What materials, sizes and styles are available?

Key-locking Inserts/ Keenserts®

Key-locking inserts come in four main styles: Miniature, Thin Wall, Heavy Duty Wall (general purpose) and Extra Heavy Duty.

  • Miniature Key-locking inserts are used in electronic and aerospace applications where size and strength are critical. These inserts may be installed in sheet material as thin as 1/16″.
  • Thinwall inserts have smaller external threads than standard heavy-duty inserts and are ideal for tight spaces where less pull-out strength is acceptable.
  • Heavy Duty inserts have a thick, heavy-duty thread wall, suitable for most applications.
  • Extra-heavy duty inserts are used in oversized and overly worn holes.

Key-locking inserts can be internally self-locking or non-locking (the standard is non-locking and is sufficient for the most common applications).

Inserts with the internal self-locking feature are designed to securely lock a bolt when it is entered into the insert only a few turns. Even after repeated installations and removals of the bolt, the lock maintains sufficient locking torque to prevent the bolt from vibrating out.

Common Materials available include Carbon steel, Stainless Steel, Alloy 4140 and A286. Nitronic and other materials may be available with a lead time.

Internal Diameters available: American/Inch #2-56 to 1 ½-6 ” and Metric M2 to M24

Helical wire inserts / Heli-Coils®

Helical wire inserts come in 2 main styles: tanged and tangless (currently, MF Supply specializes in the tanged style).

The original and widely used tang style has a prong at one end to facilitate installation. The newer tangless style has no prongs to break off, retrieve, or lose. Tangless inserts are commonly used in electronic applications where loose tangs are might cause damage.

Helical wire inserts can be free-running or self-locking.

Free running is the most common style used for thread repair. The “free” diameter of the insert is larger than the installed diameter and this configuration generates balanced pressure distribution between the coils and threads.

Self-locking style inserts are recommended for applications that require constant torque, or are subject to stress or vibration. The locking style features a crimped turn that acts as a locking mechanism that grips the bolt or screw to prevent loosening from vibration, eliminating the need for lock wiring, lock-nuts, lockwashers, pellets/patches or other thread locking devices.

Common Materials available include Stainless Steel, Phosphorous Bronze, Inconel X-750 and Nitronic 60 and 90.

Internal Diameters available: American/Inch #2-56   to   1 ½-6” and and Metric M2   to   M24.  Standard inserts lengths measure from 1x to 3x the diameter. Note: larger sizes may be available by special order.

Why use a Key-locking insert vs. a Helical wire insert?

There are three main differences between Key-locking inserts and Helical wire inserts:

1) Strength: Key-locking inserts are stronger than Helical wire inserts

2) Ease of installation: Key-locking inserts are easier to install than Helical wire inserts

3) Price: Key-locking inserts are more expensive than Helical wire inserts!

So here is some direction on how to select the correct threaded insert for your application:  In heavy wear, high vibration and high heat situations where saving space is not a concern and hole depth is limited, Key-locking inserts are the best bet.

When reducing costs and minimizing space are priorities, Helical wire inserts are the way to go. They are particularly useful for creating permanent strong threads in softer materials such as aluminum, titanium and magnesium alloys, and are best suited to lower heat and lower torque environments.

Stay tuned for our next blog, where we discuss, brands and mil-spec options, how to order and installation options!

Key-locking Inserts (Keenserts®) & Helical Wire Inserts at MF Supply

MF Supply is a WBE/WOSB woman owned business, and a trusted supplier of Keenserts & Helical Wire Inserts for manufacturers, government and industry.

We Invite You To Request a Quote, Download a Guide or a Line Card Today!

  • Full ecommerce enabled website with technical manual available 24/7
  • Same day drop ship from factory for thousands of items.
  • Functional Equivalents to expensive brand name fasteners save money and reduce long lead times.
  • Creatively solve problems including hard to find parts and long lead times
  • WBE/WOSB Woman Owned Certified Small Business.

Do you still have questions or would like to speak with a representative to request a quote? Reach out to us, and our MF Supply team of sourcing experts will help you find what you’re looking for. “Finding the right screw for you” is our tag line after all!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

Six Reasons To Buy From MF Supply

  • Full eCommerce Enabled Website With Technical Manual Available 24/7 – Visit our website and Create a New Account, track online orders, browse our product catalog, check technical specs, subscribe to our blog, or buy online.  We are adding items and improving functionality daily!
  • Same Day Shipping From The USA – Our hardware products are in stock and ship to you directly from our USA based distribution centers. 
  • Functional Equivalents To Expensive Brand Names- We stock and source alternatives to brand name fasteners, reducing long lead times and saving you money.
  • Creatively Solve Problems – We are sourcing experts, offer competitive pricing and specialize in finding hard to find parts and reducing long deliveries.
  • One-Stop Shopping On Certified Hardware – We stock and source a full line of fasteners including Mil-Spec, DFARS compliant and other industrial products.
  • WBE/WOSB Woman Owned Certified Small Business – To meet your diversity & set-aside needs.

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 


The Buyer’s Guide to Self-Clinching Fasteners You Must Have! Refreshed for 2023!

MF Supply continues to expand our offering of products available for purchase online. We are thrilled to offer Self-clinching fasteners available from stock that can be purchased on our website or by email, phone or fax. We are an authorized distributor for Captive Fasteners, a US based manufacturer since 1974, with a factory right here in our NJ backyard!

What are Self-clinching fasteners?

Self-clinching fasteners are generally classified as part of the electronic hardware or precision engineered fastener family and are not governed by IFI, ANSI or ASME standards. A self-clinching fastener, also known as press-fit or clinch style captive fastener, is a part that when pressed into a drilled, punched or machined hole, provides an economical method of joining sheet metal panel applications and is well-suited for use in printed circuit boards.

Self-clinching fasteners are used in many industries; both commercial and aerospace.

Self-clinching Fasteners available at MF Supply

MF Supply offers the full catalog of Captive branded fasteners & PEM® equivalents in inch & metric sizes. We have the following parts available for purchase online, in stock and ready to ship from our national distribution centers:

Additional Series available include, but are not limited to, floating, self-locking, blind-hole, flush, and broaching fasteners.

How do they work? 

Self-clinching fasteners work by displacing the host material around the mounting hole, causing it to cold flow into a specially designed annular recess. Knurls, serrated rings or ribs on the fastener hold them firmly in place. Self-clinching fasteners become an integral permanent part of the panel or frame and eliminate problems associated with loose hardware. Installation requires access to both sides of the panel and self-clinching fasteners may be installed using any parallel acting squeezing force.

What are the advantages of Self-Clinching fasteners?

Self-clinching fasteners provide strong thread in very thin material & offer high push out and torque out resistance. They take less space and require fewer assembly operations than caged or anchor nuts. They can be installed during fabrication or during final assembly and work well in applications when loose hardware wouldn’t be accessible.

Some of the key advantages include:

  • No special hole preparation, such as chamfering and deburring is required.
  • Low installed costs, fewer parts to handle, fewer assembly steps and less assembly time.
  • No retapping necessary after application.

What are the differences between branded fasteners like PEM & Captive and generic Self-clinching fasteners?

SelfClinchStud

Self-clinching hardware is frequently referred to by the OEM brand name PEM®. Captive Fastener is a USA based manufacturer and offers functional equivalents to PEM® branded self-clinching fasteners.  In addition to PEM® & Captive, there are a variety of manufacturers of self-clinching fasteners available in the marketplace including the major national catalog brands. Functional alternatives will be equivalent in form fit and function and offer similar performance.

To see if using alternative brands or functional equivalents will work for your business, refer to our handy guide.

We have also included a cross reference lookup table for PEM® product types vs. Captive product series below.

Also, watch our video below!

What information for I need for ordering? 

The easiest way to order is by manufacturer part number. If you don’t have one, you’ll need to specify fastener type & style, thread diameter & pitch, fastener length, material and plating. For example: a 10-32 X 3/8 Flush Head Self-Clinching Stud Steel Zinc plated can also be ordered as a PEM® FH-032-6, (or a PEM® FH-032-6-ZI as sometimes PEM® calls out the plating) or a Captive CH1032-6.  This part is also offered by a national catalog brand under part number 93580A166.

Additional Series available include, but are not limited to, floating, self-locking, blind-hole, flush, and broaching fasteners.

We Invite You To Request a Quote, Download a Guide or a Line Card Today!

  • Full ecommerce enabled website with technical manual available 24/7
  • Same day drop ship from factory for thousands of items.
  • Functional Equivalents to expensive brand name fasteners save money and reduce long lead times.
  • Creatively solve problems including hard to find parts and long lead times
  • WBE/WOSB Woman Owned Certified Small Business.

Seeking parts not listed for purchase on our website? We’ve got you covered! Submit your RFQ for your PEM®, Captive® or equivalent Self-Clinching parts, and our team of experts can help source your needs!


Book a one-on-one consultation with our President, Robin, to discuss how MF Supply can help you solve your Industrial Sourcing, Fastener, and Safety concerns.


MF Supply Work With Us

MF Supply is a WBE/WOSB certified supply chain partner to business, industry and government.  We are sourcing experts and stocking distributors of Hardware, Precision & Mil-Spec Fasteners and Safety supplies.  For more than 50 years, we have been supplying manufacturers in the electronics, industrial, commercial, aerospace and military markets with the full range of fastener products and services.  Our Cage Code is 58QG4 and our registered name is RL Supply Inc dba MF Supply. 

Read More https://conta.cc/3MFOMfm


The Buyer’s Guide to Self-Clinching Fasteners You Must Have!

Through our extensive assortment of OEM brand names and equivalents, we offer our customers quality imported and domestic self-clinching options

Read More https://conta.cc/3MFOMfm


Hardware Functional Equivalents and Sourcing Experts

At MF Supply, we spent a lot of time sourcing hard to find, back ordered, expensive, or out-of-stock OEM hardware brands. We do this in order to save money and to reduce long lead times for our customers.

Just like in the pharmaceutical world, where there are brand names that everyone knows, there are also generic brands that are functional equivalents. This is true for the hardware industry too!

What is a Functional Equivalent?

Some brand-name fasteners are also available as functional equivalents, also referred to as crossed, generics, or alternatives. These are parts that are the same in form, fit, function, material, and specifications as the brand name.

Functional Equivalents Examples and Case Studies

Below are two case studies showing how using functional equivalents has saved a lot of manufacturers a lot of money and time.

Case Study: Precision Shoulder Screw Functional Equivalent

In this case study, you can learn more about precision shoulder screw functional equivalents.

Case Study: Keensert Functional Equivalents

In this case study, you can see that smart manufacturers use brand equivalents to save time and money!

Should You Use Functional Equivalents?

On our website, we offer some of our different product reference charts that actually show you the different part numbers that all our functional equivalents.
Check it out here!

Four Point Check Checklist

  • Check your BOM- Does it call for an OEM brand?
  • Are the Lead Times going to hinder your timeline? Will having the part sooner improve the delivery of your final product.
  • Will your supplier provide you with the certificate of conformance to certify that the part is a functional equivalent to the original brand you are looking for?
  • Will saving money help you be more competitive in your market?

Learn More About MF Supply

If you are interested in learning more about saving time and money with functional equivalents, contact us at MF Supply today!


“Heli-coils” vs. “Keenserts”: 3 differences you must know-Part 1 of 2

Today we will compare 2 popular fastener products that are used to repair damaged threads or strengthen a weaker parent material like aluminum: Helical Wire Inserts and Key-locking Inserts.  Both are commonly used in precision manufacturing and aerospace applications.

What are the main uses of these threaded inserts?

Both “Heli-coil” or Helical wire inserts and “Keensert” or Key-locking inserts fall under the “Threaded Insert” category of fasteners. A threaded insert, also known as a threaded bushing, is a fastener element that is inserted into an object to add a threaded hole. They may be used to repair a stripped threaded hole, provide a durable threaded hole in a soft material, place a thread on a material too thin to accept it, mold or cast threads into a work piece thereby eliminating a machining operation, or simplify changeover from unified to metric threads or vice versa. Although Helical Wire inserts and Key-locking externally threaded inserts are used in similar ways, there are 3 main distinctions that we detail below. But first, let’s take a closer look at each of these fasteners:

What is a Helical Insert Wire Insert? (aka Heli-coil)

Helical wire inserts are precision-formed continuous wire coils that provide permanent, wear-resistant threads which exceed the strength of the parent material. Often underestimated, the popular misconception is that Helical wire inserts are intended solely for thread repair, when, in fact, they have other significant uses.  Not to be confused with other types of threaded inserts or rivnuts, Helical wire inserts resemble springs and are sometimes referred to as “Screw Thread Inserts (STI)” ,“Helicals” or by the popular brand “Heli-Coil” which is a registered trademark of Emhart® Teknologies, Inc.

Three typical applications for using Helical wire inserts are 1) to repair damaged threads in parts that would otherwise have to be scrapped; 2) to strengthen threads against failures due to stripping, seizing or corrosion; 3) to convert threads between inch and metric sizes.

What is a Key-locking insert? (aka Keensert or Keysert)

The Key-locking threaded insert is a solid bushing style insert that is threaded on both the inside and the outside and has wedges or “keys” attached to the top of the insert. These externally threaded inserts are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion. Key-locking inserts are commonly used in high torque and high temperature situations, and in applications where fasteners may be repeatedly removed and reassembled. Key-locking inserts are often referred to as Keenserts® and Keyserts, which are registered trademarks for the most popular brand names for this part. (Keensert® is a registered trademark of Huck Patents, Inc. & Keysert® is a registered trademark of Alcoa Fastening Systems).

Typical applications are transmission housings, electronic equipment and suspension units. Key-locking inserts are commonly found in aerospace assemblies.

How do they work?

Helical wire inserts work because the diamond shaped helically formed wire coil screws into a threaded hole to form a mating internal thread for a screw or stud.  

Key-locking inserts are threaded into a pre-tapped hole, and then the keys are hammered into grooves through the threads, permanently locking the insert in place. Their “keys”, which are driven down into the tapped threads, provide a mechanical lock against rotation, especially when the mating stud or bolt will be removed frequently.

What materials, sizes and styles are available?

Keenserts

Key-locking inserts come in four main styles: Miniature, Thin Wall, Heavy Duty Wall (general purpose) and Extra Heavy Duty.

  • Miniature Key-locking inserts are used in electronic and aerospace applications where size and strength are critical. These inserts may be installed in sheet material as thin as 1/16″.
  • Thinwall inserts have smaller external threads than standard heavy-duty inserts and are ideal for tight spaces where less pull-out strength is acceptable.
  • Heavy Duty inserts have a thick, heavy-duty thread wall, suitable for most applications.
  • Extra-heavy duty inserts are used in oversized and overly worn holes.

Key-locking inserts can be internally self-locking or non-locking (the standard is non-locking and is sufficient for the most common applications).

Inserts with the internal self-locking feature are designed to securely lock a bolt when it is entered into the insert only a few turns. Even after repeated installations and removals of the bolt, the lock maintains sufficient locking torque to prevent the bolt from vibrating out.

Common Materials available include Carbon steel, Stainless Steel, Alloy 4140 and A286.

Internal Diameters available: American/Inch #2-56   to   1 ½-6 ” and Metric M2 to M24

Helical wire inserts

Helical wire inserts come in 2 main styles: tanged and tangless (currently, MF Supply spcializes in the tanged style).

The original and widely used tang style has a prong at one end to facilitate installation. The newer tangless style has no prongs to break off, retrieve, or lose. Tangless inserts are commonly used in electronic applications where loose tangs are might cause damage.

Helical wire inserts can be free-running or locking.

Free running is the most common style used for thread repair. The “free” diameter of the insert is larger than the installed diameter and this configuration generates balanced pressure distribution between the coils and threads.

Locking style inserts are recommended for applications that require constant torque, or are subject to stress or vibration. The locking style features a crimped turn that acts as a locking mechanism that grips the bolt or screw to prevent loosening from vibration, eliminating the need for lock wiring, lock-nuts, lockwashers, pellets/patches or other thread locking devices.

Common Materials available include Stainless Steel, Phosphorous Bronze, Inconel X-750 and Nitronic 60 and 90.

Internal Diameters available: American/Inch #2-56   to   1 ½-6” and and Metric M2   to   M24.  Standard inserts lengths measure from 1x to 3x the diameter. Note: larger sizes may be available by special order.

Why use a Key-locking insert vs. a Helical wire insert?

There are three main differences between Key-locking inserts and Helical wire inserts:

1) Strength: Key-locking inserts are stronger than Helical wire inserts

2) Ease of installation: Key-locking inserts are easier to install than Helical wire inserts

3) Price: Key-locking inserts are more expensive than Helical wire inserts!

So here is some direction on how to select the correct threaded insert for your application:  In heavy wear, high vibration and high heat situations where saving space is not a concern and hole depth is limited, Key-locking inserts are the best bet.

When reducing costs and minimizing space are priorities, Helical wire inserts are the way to go. They are particularly useful for creating permanent strong threads in softer materials such as aluminum, titanium and magnesium alloys, and are best suited to lower heat and lower torque environments.

Stay tuned for our next blog, where we discuss, brands and mil-spec options, how to order and installation options.

We Invite You To Request a Quote, Download a Guide or a Line Card Today!

  1. Full ecommerce enabled website with technical manual available 24/7
  2. Same day drop ship from factory for thousands of items.
  3. Functional Equivalentsto expensive brand name fasteners save money and reduce long lead times.
  4. Creatively solve problems including hard to find parts and long lead times
  5. WBE/WOSB Woman Owned Certified Small Business.
Request A Quote

Please forward you comments to robin@mfsupply.com