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    41 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.

    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
    1/8
    		025/8"3/16"PTFE
    		10,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K37000000
    1/4
    		043/4"9/32"PTFE
    		10,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K3800000
    3/8
    		067/8"9/32"PTFE
    		10,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K3900000
    1/2
    		081 1/8"19/64"PTFE
    		10,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K4400000
    3/4
    		121 5/16"19/64"PTFE
    		5,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K45000000
    1
    		161 5/8"25/64"PTFE
    		5,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K46000000
    1 1/4
    		202"25/64"PTFE
    		5,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K47000000
    1 1/2
    		242 1/4"25/64"PTFE
    		3,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K48000000
    2
    		322 3/4"27/64"PTFE
    		3,000 psi @ 72° FAir, Hydraulic Fluid, Natural Gas, Oil, Water-300 to 5005530K49000000
     

    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 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
    1/4
    		7877N10100000
    1/4
    		7877N1020000
    3/8
    		3185K1110000
    3/8
    		7877N1030000
    1/2
    		3185K1120000
    1/2
    		7877N1040000
    3/4
    		3185K1130000
    3/4
    		7877N1050000
    1
    		3185K1140000
    1
    		7877N1060000
    1 1/4
    		3185K1150000
    1 1/4
    		7877N1070000
    1 1/2
    		3185K1160000
    1 1/2
    		7877N1080000
    2
    		3185K11700000
    2
    		7877N10900000
     

    Low-Pressure Plated Brass Threaded Pipe Locknuts

    Image of Product. Front orientation. Pipe Locknuts. Low-Pressure Plated Brass Threaded Pipe Locknuts.
    Used in low-pressure pipe lines, these brass locknuts have a plating that makes them shiny and improves corrosion resistance.
    Locknuts thread onto the male end of a fitting to provide extra holding power so the fitting won’t loosen from vibration.
    Chrome-Plated Brass—Chrome-plated brass locknuts are shinier and withstand corrosion better than nickel-plated brass locknuts.
    For Pipe
    Pipe
    Size
    Hex
    Wd.
    Lg.
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    For Use With
    Pressure
    Class
    Material
    Schedule
    Material
    Specs.
    Met
    Each
    NPT Female
    1/8
    		7/8"1/4"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K181000000
    1/4
    		7/8"1/4"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K18200000
    3/8
    		1"9/32"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K18300000
    1/2
    		1 9/32"5/16"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K18400000
    3/4
    		1 1/2"9/32"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K18500000
    1
    		1 3/4"11/32"200 psi @ 72° F125 psi @ 400° FAir, Natural Gas, Oil, Steam, Water125
    		Chrome-Plated Brass40
    		BrassASTM B4569162K18600000
     

    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
    1/8
    		025/8"3/16"PTFE
    		10,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K14000000
    1/4
    		043/4"9/32"PTFE
    		10,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K1600000
    3/8
    		067/8"9/32"PTFE
    		10,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K1800000
    1/2
    		081 1/8"19/64"PTFE
    		10,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K1900000
    3/4
    		121 5/16"19/64"PTFE
    		5,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K2100000
    1
    		161 5/8"25/64"PTFE
    		5,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K2300000
    1 1/4
    		202"25/64"PTFE
    		5,000 psi @ 72° F5,000 psi @ 500° FAir, Hydraulic Fluid, Natural Gas, Oil, Steam, Water-100 to 500Zinc-Yellow-Chromate-Plated SteelMachinedXXH
    		Steel1500
    		Steel5530K2500000
    1 1/2
    		242 1/4"25/64"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
    		Steel5530K2700000
    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
    		Steel5530K29000000
     

    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
     
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