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    13 Products
    About Threaded Inserts
    industrial info icon

    Choose the right threaded insert for your application and learn how to install it securely.

    Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Mil.-Spec. Key-Locking Threaded Inserts For Soft Metal.
    These inserts are manufactured and tested to meet or compare to strict standards adopted by the U.S. military. The keys drive into aluminum and other soft metal for a secure hold that won't slip or rotate, even in vibrating vehicle or aerospace parts. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    High-Strength Cadmium-Plated Alloy Steel—These inserts have the strength to stand up to high-pressure applications and a plating that helps screws thread in smoothly.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    High-Strength Cadmium-Plated Alloy Steel
    6-32
    12-28
    0.188"3/16"
    0.190"2MS51830A10395101A10200000093904A350000000
     
    18-8 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.190"2MS51830-10393904A300000093904A35000000
     

    Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Screw-Locking Seize-Resistant Key-Locking Threaded Inserts for Soft Metal.
    Create the tightest hold in aluminum and other soft metal without screws sticking. The lubricant on these inserts eases installation, and the irregularly shaped threads won’t let screws back out from vibration. Inserts have keys that drive into material to prevent them from slipping or rotating in the hole.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    Dry-Film-Lubricated Cadmium-Plated Steel—The plating creates a barrier against rust.
    Dry-Film-Lubricated 18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    Dry-Film-Lubricated Cadmium-Plated Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830A103L97255A2280000093904A350000000
     
    Dry-Film-Lubricated 18-8 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830-103L97255A114000093904A35000000
     

    Key-Locking Threaded Insert Installation Tools

    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style C.

    Style C

    Thread inserts and drive down their keys with a single tool. These tools are compatible with Keensert inserts.
    Threaded Insert Installation Tools with Spring
    Image of Product. Front orientation. Threaded Insert Installation Tools. Key-Locking Threaded Insert Installation Tools, Style C.

    Style C

    The tradespersons’ choice for installing Mil. Spec. inserts. A spring holds the sleeve under tension, so wobbles and jostles don’t interfere with a clean, professional install.
    For Thread
    Size
    For Tap Thread
    Size
    Style
    Features
    Each
    For Thin-Wall Inserts
    6-32
    12-28
    CSleeve, Threaded Tip93904A350000000
     

    Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Key-Locking Threaded Inserts for Soft Metal.
    Add strong threads in soft metal, such as aluminum. The keys on these inserts drive into holes to hold more securely than thread-locking or helical inserts. They prevent slipping and rotating, so they’re stable enough for use in vehicle or aerospace parts that experience heavy vibration. These inserts are comparable to Keensert inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    High-Strength High-Temperature A286 Stainless Steel—High temperatures won't reduce the load capacity of these inserts. They also resist chemicals such as bleach and chlorine.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    High-Strength High-Temperature A286 Stainless Steel
    6-32
    12-28
    0.172"3/16"
    0.187"2MS51830CA10393509A13000000093904A350000000
     

    Helical Threaded Insert Removal Tools

    Image of Product. Front orientation. Threaded Insert Removal Tools. Helical Threaded Insert Removal Tools.
    To remove installed helical inserts, place the tip of these tools into the insert and lightly strike the tool’s head. Then, turn the tool counterclockwise with pressure to extract the insert.
    Narrow Profile—The tip of these tools has a narrower angle than standard removal tools to reduce the chance it will dig into your material’s surface when you strike the tool.
    For Thread Size
    Mfr.
    Each
    Narrow Profile
    10-24, 10-32, 12-24, 12-28, 1/4"-20, 1/4"-28, 1/4"-32, 1/4"-80, 5/16"-18, 5/16"-24, 5/16"-32, 3/8"-16, 3/8"-24, M5, M6, M7, M8, M10
    Heli-Coil90254A320000000
     

    Thread-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Thread-Locking Threaded Inserts.
    With Loctite® adhesive already on the threads, these inserts won’t back out or vibrate loose. The adhesive reaches full strength after 72 hours. Unlike helical inserts, you can install them with a standard drill and tap. However, thread-locking inserts are difficult to remove and reuse.
    After drilling and tapping your hole, install inserts with a wrench or an installation bit. To use a wrench, thread an insert and two hex nuts onto a bolt. Then, grip and turn the top nut to drive into the hole. For slotted inserts, you can drive with a slotted screwdriver instead.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limits.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    Drive
    Style
    Pkg.
    Qty.
    Pkg.
    Each
    Thin Wall
     
    18-8 Stainless Steel
    6-32
    12-28
    0.280"14 Ga.
    0.182"Slotted
    594165A21900000094110A220000000
     

    Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Swage-Locking Threaded Inserts.
    Add strong threads to the edges of soft metal without bulging or cracking the material. These inserts have thinner walls than our key-locking and thread-locking inserts, so they don’t need as much space around them. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength 17-4 PH Stainless Steel—The strongest stainless steel inserts we offer. They handle high-stress installations, such as pump and compressor housings, and the heavy vibration of aircraft parts. They won’t rust in wet and outdoor environments but can’t withstand the harsh chemicals and acids that 316 stainless steel can.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength 17-4 PH Stainless Steel
    8-32
    12-28
    0.250"0.191"0.216"0.065"MIL-DTL-45932/193570A104000006645N1040000000
     

    Closed-End Key-Locking Threaded Inserts for Soft Metal

    Image of Product. Bottom orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.
    Image of Product. Shown In Cross Section. Side1 orientation. Threaded Inserts. Closed-End Key-Locking Threaded Inserts for Soft Metal.

    Shown

    In

    Cross

    Section

    Keep threads clear and prevent leaks. These inserts have a closed end that blocks debris and fluids from entering parts. Keys drive into soft metal, such as aluminum, so they don’t slip or rotate in the hole. Comparable to Keensert inserts, they’re more secure than thread-locking inserts.
    To install, drill and tap a hole in your material. Then, thread the insert onto the installation tool and screw it into the hole. Place the tool over the keys and hit it with a hammer to drive them in.
    Thin Wall—Use these inserts near the edge of workpieces or wherever you only have space for a small hole. They're also lighter than standard and extra-thick wall inserts for applications with strict weight limitations.
    18-8 Stainless Steel—The choice for wet and outdoor environments, these inserts resist rust and mild chemicals.
    Inserts
    Installation
    Tools
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    Drill Bit
    Size
    For Max.
    Hole Dia.
    No. of Locking
    Keys
    Specs. Met
    Each
    Each
    Thin Wall
     
    18-8 Stainless Steel
    6-32
    12-28
    0.375"3/16"
    0.187"2MIL-I-4591493508A13000000093904A350000000
     

    Installation Tools for Swage-Locking Threaded Inserts

    Image of Product. Front orientation. Threaded Insert Installation Tools. Installation Tools for Swage-Locking Threaded Inserts.
    Set swage-locking inserts into place. Use these installation tools to hand-tighten the insert into the tapped hole. Then hammer the tool to press (or swage) the knurls of the insert into the material. You should choose the tool that matches your insert’s thread size and tap thread size.
    For Thread
    Size
    For Tap Thread
    Size
    Each
    8-32
    12-28
    6645N1040000000

    Seize-Resistant Swage-Locking Threaded Inserts

    Image of Product. Bottom orientation. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Image of Specification. Front orientation. Contains Annotated. Threaded Inserts. Seize-Resistant Swage-Locking Threaded Inserts.
    Smoothly install these inserts for strong threads near the edges and corners of soft metal surfaces. They’re lubricated to prevent sticking as you thread them in. Since these have thinner walls than our key-locking and thread-locking inserts, they don’t need as much space and won't bulge or crack the material. The knurls press (swage) into the material to keep inserts in place when you tighten or loosen a screw.
    To install these inserts, you need a drill bit, a counterbore, a standard tap, an installation tool, and a hammer. Drill a hole, counterbore the top, and tap it. Place the insert into the installation tool, then hand-tighten it into the tapped hole. Strike the tool to secure the insert and drive the knurls into the surrounding material.
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel—Stronger than our 17-4 PH stainless steel inserts, these inserts absorb impact without cracking and stand up to high-pressure applications. The cadmium plating prevents corrosion in wet environments.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Inserts
    Installation
    Tools
    For
    Counterbore
    Thread
    Size
    For Tap Thread
    Size
    Installed
    Lg.
    For Max.
    Hole Dia.
    Dia.
    Dp.
    Mil. Spec.
    Each
    Each
    High-Strength Dry-Film-Lubricated Cadmium-Plated Alloy Steel
    8-32
    12-28
    0.250"0.191"0.216"0.065"MIL-DTL-45932/193572A104000006645N1040000000
     
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