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    16 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 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
    2
    		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 A3514464K589000000———0
    2
    		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———04452K679000000
     

    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.
    Aluminum—One-third the weight of steel that's the same size. Aluminum is also nonmagnetic to prevent electrical interference in nearby equipment.
    PVC Molded Gasket—Creates a seal for moisture protection.
    Serrated Facing—Grips the material surface for added stability.
    Pipe
    Size
    Features
    Specs. Met
    Pkg.
    Qty.
    Pkg.
    NPSM Thread
     
    Zinc-Plated Steel
    2
    		—CSA Certified, UL Listed107513K246000000
    2
    		PVC Molded GasketCSA Certified, UL Listed27513K31600000
    2
    		Serrated FacingCSA Certified, UL Listed17513K1240000
     
    Aluminum
    2
    		——19147T12800000
     
    NPSL Thread
     
    316 Stainless Steel
    2
    		—C-UL Listed, UL Listed17513K41300000
     
    For Plastic Fittings
    Image of Product. Front orientation. Conduit and Fittings. Conduit Locknuts, For Plastic Fittings.
    Nylon—Lightweight and chemical resistant, these fittings won't corrode.
    Pipe
    Size
    Each
    NPT Thread
     
    Nylon
    2
    		3185K117000000
    2
    		7877N10900000
     

    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.
    DIN 431—Locknuts that meet DIN 431 comply with international standards for pipe locknut dimensions.
    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
    NPSL Female
    2
    		2 7/8"17/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K217000000
     
    BSPP Female
    2
    		75 mm13 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N1900000
     

    Extreme-Pressure Stainless Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Extreme-Pressure Stainless Steel Threaded Pipe Locknuts.
    With the strength to handle extreme pressures, these locknuts can be used to connect equipment in hydraulic fluid lines.
    Locknuts have a gasket, which creates a tight seal without the need for PTFE tape; screw one onto the male end of a fitting for extra holding power.
    303 Stainless Steel—303 stainless steel locknuts have very good corrosion resistance.
    303
    Stainless Steel
    Pipe
    Size
    Dash
    Size
    Hex
    Wd.
    Lg.
    Gasket
    Material
    Max. Pressure
    @ Temp.
    For Use With
    Temp. Range,
    ° F
    Each
    NPT Female
    2
    		322 3/4"27/64"PTFE
    		3,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K490000000
     

    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.
    NSF/ANSI 61—Locknuts rated for use with drinking water meet NSF/ANSI 61 safety standards.
    For Pipe
    For
    Flange
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Specs. Met
    Food Industry
    Std.
    Each
    NPSL Female
    2
    		2 7/8"17/32"200 psi @ 72° FAir, Drinking Water, Natural Gas, Oil125
    		Brass40
    		Brass150
    		BrassASME B1.20.1, ASME B16.15, ASTM A584NSF/ANSI 61
    		4429K129000000
     

    Low-Pressure Galvanized Iron and Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Galvanized Iron and Steel Threaded Pipe Locknuts.
    The galvanized finish on these locknuts provides fair corrosion resistance. Locknuts are for use in low-pressure applications.
    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.
    Max. Steam
    Pressure @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Class
    Material
    Specs. Met
    Each
    NPSL Female
    2
    		2 7/8"0.53"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Galvanized Iron40
    		Galvanized Steel150
    		Galvanized SteelASME B16.144638K619000000
     

    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
    2
    		3 3/8"5/8"150 psi @ 72° FAir, Oil, Water150
    		356 Aluminum40
    		Aluminum125
    		Aluminum44705K419000000
     

    Extreme-Pressure Steel Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Extreme-Pressure Steel Threaded Pipe Locknuts.
    The strongest steel locknuts we offer, these can withstand extreme-pressure applications.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    For Pipe
    For
    Flange
    Pipe
    Size
    Dash
    Size
    Hex
    Wd.
    Lg.
    Gasket
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    For Use With
    Temp. Range,
    ° F
    Material
    Fabrication
    Schedule
    Material
    Class
    Material
    Each
    NPT Female
    2
    		322 3/4"27/64"PTFE
    		3,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K290000000
     
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