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    101 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 Fittings

    Use these fittings in a low-pressure pipe line.
    Straight Adapters
    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    304 Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Pipe
    Size
    304 Stainless Steel
    316 Stainless Steel
    (A)
    (B)
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    Image of Product. Female × Butt Weld. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female.

    Female × Butt

    Weld

    1/8
    		1/8
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K36400000300 psi @ 72° F150 psi @ 350° F4452K13800000
    1/4
    		1/4
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K4710000300 psi @ 72° F150 psi @ 350° F4452K1390000
    3/8
    		3/8
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K4720000300 psi @ 72° F150 psi @ 350° F4452K2110000
    1/2
    		1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K4730000300 psi @ 72° F150 psi @ 350° F4452K2120000
    3/4
    		3/4
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K4740000300 psi @ 72° F150 psi @ 350° F4452K2130000
    1
    		1
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K4750000300 psi @ 72° F150 psi @ 350° F4452K2140000
    1 1/4
    		1 1/4
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K47600000300 psi @ 72° F150 psi @ 350° F4452K21500000
    1 1/2
    		1 1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K47700000300 psi @ 72° F150 psi @ 350° F4452K21600000
    2
    		2
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K47800000300 psi @ 72° F150 psi @ 350° F4452K21700000
    2 1/2
    		2 1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K47900000300 psi @ 72° F150 psi @ 350° F4452K21800000
    3
    		3
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K48100000300 psi @ 72° F150 psi @ 350° F4452K21900000
    4
    		4
    		150
    		300 psi @ 72° F150 psi @ 350° F4464K48200000300 psi @ 72° F150 psi @ 350° F4452K221000000
     
    BSPT Female × Butt Weld
    Image of Product. Female × Butt Weld. Front orientation. Pipe and Fittings. Low-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters, Butt-Weld Fitting Connection, Threaded Fitting Connection, Female.

    Female × Butt

    Weld

    1/8
    		1/8
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T2410000—————0
    1/4
    		1/4
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T2420000—————0
    3/8
    		3/8
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T2430000—————0
    1/2
    		1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T2440000—————0
    3/4
    		3/4
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T2450000—————0
    1
    		1
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T24600000—————0
    1 1/2
    		1 1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T24700000—————0
    2
    		2
    		150
    		300 psi @ 72° F150 psi @ 350° F4810T24800000—————0
     

    Medium-Pressure Stainless Steel Threaded Pipe Fittings

    Choose these fittings when you want the same high-quality found in our low-pressure pipe fittings, but need more strength to handle higher pressures.
    Straight Adapters
    Image of Product. Female x Butt Weld. Front orientation. Pipe and Fittings. Medium-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female.

    Female x Butt

    Weld

    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    304 Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Pipe
    Size
    304
    Stainless Steel
    316
    Stainless Steel
    (A)
    (B)
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    NPT Female × Butt Weld
    1/8
    		1/8
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K221000004452K51100000
    1/4
    		1/4
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K22200004452K5120000
    3/8
    		3/8
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K22300004452K3130000
    1/2
    		1/2
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K22400004452K3140000
    3/4
    		3/4
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K22500004452K31500000
    1
    		1
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K226000004452K31600000
    1 1/4
    		1 1/4
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K78000004452K51700000
    1 1/2
    		1 1/2
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K79000004452K51800000
    2
    		2
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K81000004452K51900000
    2 1/2
    		2 1/2
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K161000004452K631000000
    3
    		3
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K2270000004452K632000000
    4
    		4
    		1000
    		1,000 psi @ 72° F650 psi @ 350° F4464K2280000004452K633000000
     

    High-Pressure Stainless Steel Threaded Pipe Fittings

    Use these heavy duty fittings in high-pressure flow applications.
    Straight Adapters
    Image of Product. Female x Butt Weld. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female.

    Female x Butt

    Weld

    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    304 Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Pipe
    Size
    Dash
    Size
    304 Stainless Steel
    316 Stainless Steel
    (A)
    (B)
    (A)
    (B)
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    NPT Female × Butt Weld
    1/8
    		1/8
    		02023000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K571000003,000 psi @ 72° F2,800 psi @ 350° F4443K671000000
    1/4
    		1/4
    		04043000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K572000003,000 psi @ 72° F2,800 psi @ 350° F4443K67200000
    3/8
    		3/8
    		06063000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K573000003,000 psi @ 72° F2,800 psi @ 350° F4443K67300000
    1/2
    		1/2
    		08083000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K574000003,000 psi @ 72° F2,800 psi @ 350° F4443K67400000
    3/4
    		3/4
    		12123000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K575000003,000 psi @ 72° F2,800 psi @ 350° F4443K67500000
    1
    		1
    		16163000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K576000003,000 psi @ 72° F2,800 psi @ 350° F4443K67600000
    1 1/4
    		1 1/4
    		20203000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K577000003,000 psi @ 72° F2,800 psi @ 350° F4443K67700000
    1 1/2
    		1 1/2
    		24243000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K578000003,000 psi @ 72° F2,800 psi @ 350° F4443K678000000
    2
    		2
    		32323000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K579000003,000 psi @ 72° F2,800 psi @ 350° F4443K679000000
    2 1/2
    		2 1/2
    		40403000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K1710000003,000 psi @ 72° F2,800 psi @ 350° F4443K171000000
    3
    		3
    		48483000
    		2,500 psi @ 72° F1,900 psi @ 350° F45525K1720000003,000 psi @ 72° F2,800 psi @ 350° F4443K172000000
     

    Premium Low-Pressure Stainless Steel Threaded Pipe Fittings

    Unlike other stainless steel fittings, these are cast in the U.S. for superior quality. As another marker of quality, they come with a certificate with a traceable lot number and test report that guarantees material composition. All fittings except plugs adhere to ANSI/MSS SP-114 standards for heat treating, material thickness, and marking. It’s the highest quality standard for Pressure Class 150 low-pressure stainless steel fittings. They also meet either ASTM A351 or A479 requirements for parts that will be used in pressure systems. These stainless steel fittings are more corrosion resistant than steel fittings, and almost as strong.
    Material Certificate Icon
    Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.
    Straight Adapters
    Image of Product. Female x Butt Weld. Front orientation. Pipe and Fittings. Premium Low-Pressure Stainless Steel Threaded Pipe Fittings, Straight Adapters, Threaded Fitting Connection, Butt-Weld Fitting Connection, Female.

    Female x Butt

    Weld

    Threaded Fitting Connection—Threaded female x butt weld straight adapters are also known as half couplings.
    304 Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316 Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Pipe
    Size
    304
    Stainless Steel
    316
    Stainless Steel
    (A)
    (B)
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Each
    NPT Female × Butt Weld
    1 1/2
    		1 1/2
    		150
    		300 psi @ 72° F150 psi @ 350° F90691A16400000090697A164000000
    2
    		2
    		150
    		300 psi @ 72° F150 psi @ 350° F90691A1650000090697A16500000
    3
    		3
    		150
    		300 psi @ 72° F150 psi @ 350° F90691A16600000090697A166000000
    4
    		4
    		150
    		300 psi @ 72° F150 psi @ 350° F90691A16700000090697A167000000
     

    High-Pressure Stainless Steel Socket-Connect Pipe Fittings

    Forged for excellent strength, these heavy duty socket-connect fittings stand up to high-pressure applications. They are easier to weld than butt-weld fittings because the fitting doesn’t need to align perfectly to the pipe. Slide pipe into the socket and weld for a strong, permanent connection.
    Straight Adapters
    Image of Product. Female × Butt Weld. Front orientation. Pipe and Fittings. High-Pressure Stainless Steel Socket-Connect Pipe Fittings, Straight Adapters, Socket Connect Female × Butt Weld.

    Female × Butt

    Weld

    Socket Connect Female × Butt Weld—Socket connect x butt weld straight adapters are also known as half couplings.
    304/304L Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.
    316/316L Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.
    Pipe
    Size
    Dash
    Size
    304/304L Stainless Steel
    316/316L Stainless Steel
    (A)
    (B)
    (A)
    (B)
    OD
    Pressure
    Class
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    Socket Connect Female × Butt Weld
    1/8
    		1/8
    		02023/4"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K3110000003,000 psi @ 72° F1,900 psi @ 350° F45515K411000000
    1/4
    		1/4
    		04047/8"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K312000003,000 psi @ 72° F1,900 psi @ 350° F45515K41200000
    3/8
    		3/8
    		06061 1/16"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K313000003,000 psi @ 72° F1,900 psi @ 350° F45515K41300000
    1/2
    		1/2
    		08081 1/4"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K314000003,000 psi @ 72° F1,900 psi @ 350° F45515K41400000
    3/4
    		3/4
    		12121 1/2"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K315000003,000 psi @ 72° F1,900 psi @ 350° F45515K41500000
    1
    		1
    		16161 13/16"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K316000003,000 psi @ 72° F1,900 psi @ 350° F45515K41600000
    1 1/2
    		1 1/2
    		24242 1/2"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K31800000—————0
    2
    		2
    		32323"3000
    		2,500 psi @ 72° F1,900 psi @ 350° F44965K3190000003,000 psi @ 72° F1,900 psi @ 350° F45515K419000000
     
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