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    18 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.
    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
    1/8
    		11/16"3/16"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Steel40
    		SteelIron, SteelASME B16.1444605K43300000
    1/4
    		27/32"1/4"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Steel40
    		SteelIron, SteelASME B16.1444605K4340000
    3/8
    		1"9/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2110000
    1/2
    		1 3/16"5/16"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2120000
    3/4
    		1 7/16"11/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2130000
    1
    		1 3/4"3/8"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21400000
    1 1/4
    		2 3/32"27/64"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K2150000
    1 1/2
    		2 11/32"15/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21600000
    2
    		2 7/8"17/32"Not RatedNot RatedAir, Natural Gas, Oil, Steam, Water150
    		Iron40
    		SteelIron, SteelASME B16.1444605K21700000
     
    BSPP Female
    1/8
    		19 mm6 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N110000
    1/4
    		22 mm6 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N120000
    3/8
    		27 mm7 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N130000
    1/2
    		32 mm8 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N140000
    3/4
    		36 mm9 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N150000
    1
    		46 mm10 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N1600000
    1 1/4
    		55 mm11 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N1700000
    1 1/2
    		60 mm12 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N1800000
    2
    		75 mm13 mmNot RatedNot RatedAir, Natural Gas, Oil, Steam, Water—Steel—SteelSteelDIN 4313555N1900000
     
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