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    24 Products
    About Pipe and Fittings
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    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.
    DIN 431—Locknuts that meet DIN 431 comply with international standards for pipe locknut dimensions.
    304
    Stainless Steel
    Pipe
    Size
    Max. Pressure
    @ Temp.
    Max. Steam
    Pressure @ Temp.
    For Use With
    For Pipe Material
    For Flange Material
    Specs.
    Met
    Each
    BSPP Female
    1/8
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N10100000
    1/4
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N1020000
    3/8
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N1030000
    1/2
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N1040000
    5/8
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N1050000
    3/4
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N1060000
    1
    		Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water304 Stainless Steel, 304/304L Stainless Steel304 Stainless Steel, 304/304L Stainless SteelDIN 4319027N10700000
     

    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.
    Pipe
    Size
    Hex Wd.,
    mm
    Lg.,
    mm
    Max. Pressure
    @ Temp.
    Max. Steam
    Pressure @ Temp.
    For Use With
    Material
    For Pipe
    Material
    For Flange
    Material
    Specs.
    Met
    Each
    BSPP Female
    1/8
    		196Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N1100000
    1/4
    		226Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N120000
    3/8
    		277Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N130000
    1/2
    		328Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N140000
    3/4
    		369Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N150000
    1
    		4610Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N1600000
    1 1/4
    		5511Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N1700000
    1 1/2
    		6012Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N1800000
    2
    		7513Not RatedNot RatedAir, Natural Gas, Oil, Steam, WaterSteelSteelSteelDIN 4313555N1900000
     

    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.
    DIN 431—Locknuts that meet DIN 431 comply with international standards for pipe locknut dimensions.
    Pipe
    Size
    Hex Wd.,
    mm
    Lg.,
    mm
    Max. Pressure
    @ Temp.
    For Use With
    Material
    For Pipe
    Material
    For Flange
    Material
    Specs.
    Met
    Each
    BSPP Female
    1/8
    		196Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N1100000
    1/4
    		226Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N120000
    3/8
    		277Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N130000
    1/2
    		328Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N140000
    3/4
    		369Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N150000
    1
    		4610Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N1600000
    1 1/4
    		5511Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N1700000
    1 1/2
    		6012Not RatedAir, Natural Gas, OilBrassBrassBrassDIN 4313538N1800000
     
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