Buyer’s Guide to One and done Keensert® Ordering

keenserts installation

Your 5 point checklist to getting it right the first time

What is a Keensert®?

Keenserts® are solid bushing style inserts that are threaded on both the inside and the outside, and have wedges or “keys” attached at the top. They are generically called key-locking inserts, and are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion. They are commonly used in precision manufacturing and aerospace applications.

Although the name Keensert® is often used generically (like Band-Aid® or Kleenex®), Keensert®  is the registered trademark of Huck Patents (its close cousin, the Keysert® is a registered trademark of Alcoa Fastening Systems.).

How do I simplify my buying process to get what I need to complete the job on time and right?

We are all familiar with that classic adage “Measure twice, cut once”.  Nowhere is this more relevant than in the world of manufacturing.  If you are involved in procurement, you are challenged with making sure you have the right parts available at the best price  so your factory can deliver on time and on budget.   Missing tools, incorrect paperwork and long delivery times can cause major headaches and negatively impact service levels.

Our goal is to help you make the Keensert buying process easier, which in turn will eliminate stress, reduce multiple shipments and potentially increase your profits.  The result?  Happier customers (and finance departments too)!  So here it goes…..

  1. Make sure to order the correct part.

Due to the price, availability and high minimum order requirements of Huck or Alcoa branded Keensert® parts,  using functional equivalents including Mil-Spec parts has become a common practice.   Request that your supplier makes reference to the part number listed on your bill of materials on their sales order and packing slip. This will ensure you are getting the functional equivalent that you need.

If you are not ordering by part number, make sure to call out both the internal and external thread including the thread class (UNC, UNF, UNJ), the material and plating, and any special finish you need.

  1. Place blanket orders for your total project needs to get the best price and ensure availability of parts when you need them.

Most standard size non-locking miniature and thin wall / light weight Keenserts® are readily available off the shelf in 303 stainless steel or carbon steel.  However, some locking style, nonstandard diameters, 4140 alloy, A286, heavy duty, extra heavy duty, solid and floating style Keenserts® are available only by special order and usually involve a long lead time.  Make sure to get current price and delivery and order parts as early as possible.  Many suppliers allow you to order now and ship later, which can prevent delivery delays.

If you have an ongoing project, calculate your total needs and place your order with staggered delivery dates.  This will get you the best available pricing and ensure you have the parts when you need them.  Remember, price breaks can start at as few as 100 pieces.

  1. Order (the correct) installation tools with Keenserts® for maximum efficiency.

Whereas most common size and material installation tools are readily available off the shelf, less popular sizes and materials might involve a lead time.  Parent materials harder than RC30 or Anondized Aluminum may require that the tapped holes be broached for the keys, which requires the use of broach blades.

 

broaching tool

In addition, there are manual and power installation tools to choose from, so consult with your supplier on which tool is correct for your job.  Note:  manual tools work well for jobs up to 999 Keenserts®.  For installations of 1000 Keenserts® or more, a pneumatic tool is recommended.

  1. Order the Correct drills and taps for proper installation

Although Keenserts® are installed with standard drills and taps (plus the installation tool and a hammer) each part has a specific hole/tap dimensional recommendation. The drills used are often oversized for the external thread size.  When purchasing key-locking inserts, check with your production department to make sure you have everything you need for proper installation. Note: Drill is oversize see charts for proper dimensions.

Kits are handy to have in the shop and are available for most common sizes.  These kits include 2+ Keenserts®, the associated drill, tap and manual installation tool along with instructions for correct installation.

  1. Request COC, MTRs, DFAR and all required paperwork on your RFQ and PO.

Since using functional equivalents including Mil-Spec parts is a common practice, make sure you have dotted your i’s and crossed your t’s when it comes to paperwork.  Ask your supplier to reference the branded part number listed on your bill of materials on their COC and packing slip to make sure you are getting the functional equivalent that you need.  In most cases, a Certificate of Conformance or a COC referencing the part number you ordered is all the paperwork you need.  Certain aerospace customers need a complete Manufacturer’s Test Report (MTR) package including DFAR statement and passivation certs with full lot traceability.  This might involve a fee, so include it in your RFQ.  Whatever your requirement, include it on your Purchase Order to make sure you have what you need to satisfy your customer’s needs.

In summary, follow this handy 5 point guide when ordering Keenserts® and watch your costs decrease and your service levels soar!

For more information about MF Supply contact:

Robin Lieberman, President
robin@mfsupply.com
973-777-5411


Keensert® Buyer’s Guide

Keensert® Buyer’s Guide

5 Things You Need to Know

If you are a precision manufacturer working in high-torque and high-temperature situations, you might already be familiar with Keensert® key-locking inserts.  Common uses include thread repair applications or to provide thread durability in situations such as aerospace assemblies, electronic equipment and suspension units.

But, what exactly are they and what should you know before buying them? We’d like to help you out with this quick buyer’s guide.

  1. What is a Keensert®?

A Keensert® is a solid bushing style insert that is threaded on both the inside and the outside, and has wedges or “keys” attached at the top. They are generically called key-locking inserts, and are used to distribute loads and repair or strengthen threads against failures due to stripping, seizing or corrosion.

Although the name Keensert® is often used generically (like Band-Aid® or Kleenex®), Keensert®  is the registered trademark of Huck Patents (its close cousin, the Keysert® is a registered trademark of Alcoa Fastening Systems.).

Before you shop, check to see if the bill of materials specifically calls out Huck or Alcoa brand as the Keensert®  manufacturer. If no specific manufacturer’s name is listed, then you can typically use an alternative like Rock Solid brand, a generic equivalent or cross to a MIL-SPEC part.  This becomes important due to price and availability of the brand name parts.

  1. What materials and sizes are available?

Keenserts are available off the shelf in 303 stainless steel or carbon steel. Standard diameters are: American #6-32 to 1 ½” and Metric  M4 to M24. Other diameters (starting at 2-56 and M2) and materials (including 316 stainless steel, and alloys 4140 and A286) are available for special order and usually involve a lead time.

  1. What information do I need for ordering?

To order, you’ll need the manufacturer’s part number or the internal and external thread and material. Alternatively, key-locking inserts often show up under their MIL-SPEC numbers, which can often be crossed to commercial equivalents. Common MIL-SPEC numbers include: MS51830, MS51831, MS51832, NAS1394, NAS1395, NA0146, NA0147, NA0148, NA0149, NA150, and NA0151.

  1. Do I need to buy special installation tools?

When purchasing key-locking inserts, check with your production department to make sure you have the tools you need to properly install inserts. You can buy kits that include a tap, drill, and installation tool.

  1. What level of certification is required?

Generally, a Certificate of Conformance or a COC is sufficient. Full certification with material certs and test reports are often available for a fee.

In summary, in order to have the most efficient Keensert shopping/buying experience, be prepared with the following information before you shop:  Do you need the Alcoa or Huck brand product or can you use a generic or MIL-SPEC alternative?  Make sure to have the manufacturer’s part number, MIL-SPEC part number or the internal/external thread and material.  Do you need an installation tool? Finally, check to see if you require a standard COC or full certs.

For more information about MF Supply contact:

Robin Lieberman, President
robin@mfsupply.com
973-777-5411

 


What the heck is a Keensert® Key-locking insert?

 

 

What the heck is a Keensert® Key-locking insert?

Image

  Key-locking insert 

 

We close out the first quarter of 2013 by introducing you to the Keensert Key-locking insert. Like its relative, the Helical wire insert, (see January 2013), the Key-locking insert was originally designed to repair parts with damaged threads.

What is a Keensert Key-locking insert?

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. Keensert® is the registered trademark for one of the most popular brand names for this part and is used commonly to describe this insert.

Who uses Key-locking inserts?

Generally, Key-locking inserts are used to distribute loads and strengthen or repair 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.

Typical applications are transmission housings, electronic equipment and suspension units. Key-locking inserts are common in the aerospace industry.

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

There are three main differences between Key-locking inserts and Helical Wire Inserts: Key-locking inserts are stronger than helical wire inserts, they are easier to install than helicals, and they are more expensive!

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. 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.

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.

What styles are available?

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

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.

General-purpose 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.

Installation is 5 easy steps!

1) Drill with a standard tap drill and countersink with a standard 82° – 100° countersink (90° for Miniature Inserts). Note: Drill is oversize see charts for proper dimensions.

2) Tap new threads with a standard tap.

3) Screw in the insert until it is .010-.030 (.005-.015 for Miniature Inserts) below the surface. Keys locate the proper depth.

4) Drive keys down with several hammer taps on the proper installation tool.

5) You are done!  

 

Considerations for selecting and using Key-locking inserts.

  • Inserts often show up under their Mil-spec numbers, which can be crossed to commercial equivalents. Some common Mil-spec series for Key-locking inserts include: MS5180, MS51831, MS51832, NAS1394, NAS1395, NA0146, NA0147, NA0148, NA0149, NA150, NA0151.
  • As discussed, Key-locking inserts are often referred to by their brand names, which can often be substituted by generic equivalents. Popular brands include: Alcoa, Fairchild, Keensert and Tridair.
  • Materials available include Carbon steel, Stainless Steel, Alloy 4140 and A286.
  • Diameters available: American – #6   to   1 1/2 ” and Metric – M4   to   M24
Key-locking inserts at MF SupplyWe offer:  

  • The full range of commercial and mil-spec parts
  • Products kits including single and multiple sizes
  • We are authorized distributors for Chrislynn and E-Z Lok

For more detailed information on Key-locking insert, visit us at http://www.mfsupply.com/Keensert_Style_Inserts_s/1864.htm

And if you don’t see it listed, as always, ask us. Finding the right screw for you is our tag line after all!