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    9 Products
    About Pipe and Fittings
    industrial info icon

    Measure your pipe and fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

    Low-Pressure Iron and Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Iron and Steel Threaded Pipe Locknuts.
    Use these locknuts for low-pressure applications in noncorrosive environments.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPTF (Dryseal) threads, NPSC (National Pipe Straight Coupling) threads, and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    For Flange
    Material
    Specs. Met
    Each
    NPT Female
    3
    		4 1/4"11/16"175 psi @ 72° F125 psi @ 350° FAir, Natural Gas, Oil, Steam, Water125
    		Iron40
    		SteelIron, SteelASME B1.20.1, ASME B16.444605K488000000
     

    Low-Pressure Stainless Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Stainless Steel Threaded Pipe Locknuts.
    Use these locknuts in a low-pressure pipe line.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPTF (Dryseal) threads and NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    304 Stainless Steel—304 stainless steel locknuts have very good corrosion resistance.
    316 Stainless Steel—316 stainless steel locknuts have excellent corrosion resistance.
    ANSI/MSS SP-114—Locknuts that meet ANSI/MSS SP-114 adhere to high-quality standards for heat treating, material thickness, and marking.
    For Pipe
    For
    Flange
    304
    Stainless Steel
    316
    Stainless Steel
    Pipe
    Size
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Fabrication
    Schedule
    Material
    Class
    Material
    Specs. Met
    Each
    Each
    NPSL Female
    3
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		304 Stainless Steel, 304/304L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A3514464K592000000———0
    3
    		300 psi @ 72° F150 psi @ 350° FAir, Natural Gas, Oil, Steam, Water150
    		Heat Treated40
    		316 Stainless Steel, 316/316L Stainless Steel150
    		304 Stainless Steel, 304/304L Stainless SteelANSI/MSS SP-114, ASTM A351———04452K682000000
     

    Conduit Locknuts

    Secure threaded conduit fittings to knockouts. These locknuts keep fittings from shifting, so connections stay stable and wiring is protected inside electrical boxes or enclosures.
    For Metal and Plastic Fittings
    Image of Product. Front orientation. Conduit and Fittings. Conduit Locknuts, For Metal and Plastic Fittings.
    Image of Product. Locknut with PVC Molded Gasket. Front orientation. Conduit and Fittings. Conduit Locknuts, For Metal and Plastic Fittings, PVC Molded Gasket.

    Locknut with

    PVC Molded

    Gasket

    Image of Product. Locknut with Serrated Facing. Front orientation. Conduit and Fittings. Conduit Locknuts, For Metal and Plastic Fittings, Serrated Facing.

    Locknut

    with

    Serrated

    Facing

    Zinc-Plated Steel—The strength of steel with a plating that protects from occasional exposure to moisture.
    316 Stainless Steel—Our most corrosion-resistant fittings won't degrade when exposed to salt water and harsh chemicals.
    PVC Molded Gasket—Creates a seal for moisture protection.
    Serrated Facing—Grips the material surface for added stability.
    Pipe
    Size
    Features
    Specs. Met
    Each
    NPSM Thread
     
    Zinc-Plated Steel
    3
    		—CSA Certified
    		7513K11200000
    3
    		PVC Molded GasketCSA Certified
    		7513K11600000
    3
    		Serrated FacingCSA Certified
    		7513K12600000
     
    NPSL Thread
     
    316 Stainless Steel
    3
    		—C-UL Listed, UL Listed7513K15200000
     

    Low-Pressure Aluminum Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Aluminum Threaded Pipe Locknuts.
    In addition to being lightweight, these aluminum locknuts offer good corrosion resistance. Use them in low-pressure flow applications. To prevent cracking, do not tighten more than a 1/4-turn past hand tight.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Each
    NPSL Female
    3
    		4 1/2"15/16"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K332000000
     

    Low-Pressure Brass and Bronze Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Brass and Bronze Threaded Pipe Locknuts.
    Use these locknuts in low-pressure flow applications. They have good corrosion resistance.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    NPSL Thread—NPSL (National Pipe Straight Locknut) threads are compatible with NPT threads.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Specs. Met
    Each
    NPSL Female
    3
    		4 1/4"5/8"200 psi @ 72° FAir, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B16.154429K465000000
     
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