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    65 Products

    Hydraulic Pressure-Relief Valves

    Image of Product. Iron. Front orientation. Pressure-Relief Valves. Hydraulic Pressure-Relief Valves, Iron Body.

    Iron

    To set the pressure, unscrew the cap and turn the adjustment screw. Valves begin opening at the set pressure and fully open at about 10% over the set pressure. They begin closing as pressure drops and close when the system pressure is restored below the set pressure.
    Iron Body—Iron valves absorb vibration to reduce noise and wear in the pipeline.
    Inlet
    Connection
    Relief
    Connection
    Overall
    Pipe
    Size
    Dash
    Size
    Pipe
    Size
    Dash
    Size
    Lg.
    Wd.
    Ht.
    Temp. Range,
    ° F
    Choose a Set Pressure, psi
    Each
    NPT Female Inlet and NPT Female Relief Port
     
    Iron Body
    3/8
    063/8
    062 1/16"1 3/8"5 3/8"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K320000000
    1/2
    081/2
    082 5/16"1 7/16"6 3/16"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K11000000
    3/4
    123/4
    122 11/16"1 11/16"6 15/16"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K12000000
    1
    161
    163 5/16"2 1/16"8 1/4"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K13000000
    1 1/4
    201 1/4
    203 13/16"2 1/2"9 9/16"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K14000000
    1 1/2
    241 1/2
    244 1/8"2 7/8"11 1/16"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 300 to 5004704K25000000
    2
    322
    324 5/8"3 1/4"13"-20 to 4003 to 10, 7 to 35, 30 to 100, 60 to 175, 150 to 350, 250 to 6004704K26000000
     

    Large-Diameter Remote-Discharge Fast-Acting Pressure-Relief Valves for Air and Inert Gas

    Commonly used with high-volume blowers, compressors, and air-powered conveyors, these valves quickly relieve a large amount of air in systems with a pipe size of 2 or greater. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. Attach a drain line to the threaded relief port for remote discharge. Valves have a cast iron body to absorb vibration for reduced noise and wear in your pipeline.
    NPT Male Inlet and NPT Female Relief Port
    Image of Product. Front orientation. Pressure-Relief Valves. Large-Diameter Remote-Discharge Fast-Acting Pressure-Relief Valves for Air and Inert Gas.
    Inlet
    Relief
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Port Pipe
    Size
    Port
    Location
    Shape
    Overall
    Ht.
    For Use With
    Temp. Range,
    ° F
    Test
    Mechanism
    Valve
    Type
    Choose a Set Pressure, psi
    Each
     
    Cast Iron Body—Bronze Seal
    2
    Bottom602
    Side90° Elbow7"Air, Inert Gas-20 to 406T-HandlePop Safety2, 4, 6, 8, 10, 12, 148175K310000000
    2 1/2
    Bottom602 1/2
    Side90° Elbow8"Air, Inert Gas-20 to 406T-HandlePop Safety2, 4, 6, 8, 10, 12, 148175K33000000
    3
    Bottom603
    Side90° Elbow9"Air, Inert Gas-20 to 406T-HandlePop Safety2, 4, 6, 8, 10, 12, 148175K3500000000
     

    Vibration-Damping Pressure-Regulating Valves for Water, Oil, Air, and Inert Gas

    Image of Product. Front orientation. Pressure-Regulating Valves. Vibration-Damping Pressure-Regulating Valves for Water, Oil, Air, and Inert Gas.
    A cast iron body absorbs vibration from pressure changes to reduce wear and noise in your pipeline. These valves automatically reduce a high, variable inlet pressure to a lower, stable outlet pressure. Adjust the outlet pressure within the range.
    Internal Strainer—Internal strainers trap debris.
    Inlet
    Outlet
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Pipe
    Size
    Location
    Pressure Adjustment
    Method
    End-to-End
    Lg.
    For Use With
    Temp. Range,
    ° F
    Choose an Outlet Pressure, psi
    Each
    NPT Female
     
    Cast Iron Body—Buna-N Diaphragm and Seal with Internal Strainer
    1/4
    Side2001/4
    SideScrew3"Water, Oil, Air, Inert Gas32 to 1802 to 25, 20 to 604674K410000000
    3/8
    Side2003/8
    SideScrew3 7/8"Water, Oil, Air, Inert Gas32 to 1802 to 30, 20 to 70, 40 to 110, 90 to 1504674K42000000
    1/2
    Side2001/2
    SideScrew4 1/2"Water, Oil, Air, Inert Gas32 to 1802 to 30, 10 to 50, 30 to 125, 50 to 1254674K43000000
    3/4
    Side2003/4
    SideScrew5 1/8"Water, Oil, Air, Inert Gas32 to 1802 to 20, 10 to 35, 30 to 75, 50 to 110, 105 to 1254674K44000000
    1
    Side2001
    SideScrew5 7/8"Water, Oil, Air, Inert Gas32 to 1802 to 20, 10 to 45, 20 to 60, 55 to 100, 90 to 1254674K45000000
    1 1/4
    Side2001 1/4
    SideScrew6 3/4"Water, Oil, Air, Inert Gas32 to 1802 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 1504674K46000000
    1 1/2
    Side2001 1/2
    SideScrew6 3/4"Water, Oil, Air, Inert Gas32 to 1802 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 1254674K47000000
    2
    Side2002
    SideScrew9 1/4"Water, Oil, Air, Inert Gas32 to 1802 to 20, 10 to 60, 20 to 100, 90 to 1254674K4800000000
     
    Cast Iron Body—Fluoroelastomer Diaphragm and 420 Stainless Steel Seal
    3/8
    Side2503/8
    SideScrew4 1/4"Water, Oil, Air, Inert Gas32 to 3000 to 10, 10 to 50, 40 to 100, 100 to 2009796K11000000
    1/2
    Side2501/2
    SideScrew3 5/8"Water, Oil, Air, Inert Gas32 to 3000 to 10, 10 to 50, 40 to 100, 100 to 2009796K12000000
    3/4
    Side2503/4
    SideScrew3 5/8"Water, Oil, Air, Inert Gas32 to 3000 to 10, 10 to 50, 40 to 100, 100 to 2009796K13000000
    1
    Side2501
    SideScrew4 1/2"Water, Oil, Air, Inert Gas32 to 3000 to 10, 10 to 30, 30 to 50, 40 to 859796K14000000
    2
    Side2502
    SideScrew6 1/2"Water, Oil, Air, Inert Gas32 to 3000 to 10, 10 to 30, 30 to 50, 40 to 859796K15000000
     

    Pressure-Regulating Inline Hydraulic Valves

    Image of Product. Front orientation. Pressure-Regulating Valves. Pressure-Regulating Inline Hydraulic Valves.
    When input pressure varies, use these valves to maintain a consistent pressure. They are often placed after a directional-control valve and before an actuator, such as a cylinder. They have an indicator/gauge port for the inlet and one for the outlet so you can monitor that output pressure remains steady.
    Inlet/Outlet
    Connection
    Relief
    Connection
    Overall
    Pipe
    Size
    Dash
    Size
    Pipe
    Size
    Dash
    Size
    Max. Flow
    Rate, gpm
    Max. Pressure,
    psi
    Lg.
    Wd.
    Ht.
    For Use With
    Choose a Set Pressure, psi
    Each
    NPT Female Inlet and Relief Port
     
    Cast Iron Body—Buna-N Seal
    3/4
    121/4
    04333,0005 7/8"3 3/4"7 1/8"Hydraulic Fluid100 to 1,000, 500 to 2,000, 1,000 to 3,0009474T20000000
     

    Large-Diameter Remote-Discharge ASME-Code Fast-Acting Pressure-Relief Valves for Air and Inert Gas

    These valves meet ASME Code Section VIII for use with air and inert gas pressure vessels. Commonly used with high-volume blowers, compressors, and air-powered conveyors, they quickly relieve a large amount of air in systems with a pipe size of 2 or greater. They spring fully open at the set pressure and remain open until the system pressure is restored below the set pressure. Attach a drain line to the threaded relief port for remote discharge. Valves have a cast iron body to absorb vibration for reduced noise and wear in your pipeline.
    NPT Male Inlet and NPT Female Relief Port
    Image of Product. Front orientation. Pressure-Relief Valves. Large-Diameter Remote-Discharge ASME-Code Fast-Acting Pressure-Relief Valves for Air and Inert Gas.
    Inlet
    Relief
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Port Pipe
    Size
    Port
    Location
    Shape
    Overall
    Ht.
    For Use With
    Temp. Range,
    ° F
    Test
    Mechanism
    Valve
    Type
    Certification
    Choose a Set Pressure, psi
    Each
     
    Cast Iron Body—Bronze Seal
    2
    Bottom602
    Side90° Elbow7"Air, Inert Gas-20 to 406T-HandlePop SafetyASME BPVC.VIII
    16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 608175K320000000
    2 1/2
    Bottom602 1/2
    Side90° Elbow8"Air, Inert Gas-20 to 406T-HandlePop SafetyASME BPVC.VIII
    16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 608175K34000000
    3
    Bottom603
    Side90° Elbow9"Air, Inert Gas-20 to 406T-HandlePop SafetyASME BPVC.VIII
    16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 608175K3600000000
     

    Back-Pressure-Regulating Valves for Water and Oil

    Image of Product. Front orientation. Pressure-Regulating Valves. Back-Pressure-Regulating Valves for Water and Oil.
    Commonly used as bypass lines after centrifugal, reciprocating, and rotary pumps, these valves obstruct flow to maintain sufficient operating pressure in your system. If the system pressure exceeds the set pressure, they exhaust through the threaded relief port. Adjust the set pressure within the range. Valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline.
    Inlet
    Outlet
    Relief
    Port
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Pipe
    Size
    Location
    Pressure Adjustment
    Method
    Pipe
    Size
    Location
    End-to-End
    Lg.
    For Use
    With
    Temp. Range,
    ° F
    Choose an Outlet Pressure, psi
    Each
    NPT Female
     
    Cast Iron Body—Nickel Diaphragm and 303 Stainless Steel Seal
    1/2
    Side4001/2
    SideScrew1/2
    Bottom2 7/8"Water, Oil-40 to 2000 to 25, 5 to 50, 30 to 100, 75 to 175, 150 to 4004675K21000000000
    1 1/4
    Side4001 1/4
    SideScrew1 1/4
    Bottom4 1/4"Water, Oil-40 to 20020 to 85, 40 to 125, 50 to 230, 175 to 380, 300 to 4004675K2500000000
    1 1/2
    Side4001 1/2
    SideScrew1 1/2
    Bottom5"Water, Oil-40 to 20010 to 55, 30 to 100, 40 to 200, 125 to 300, 200 to 4004675K2600000000
    2
    Side4002
    SideScrew2
    Bottom5"Water, Oil-40 to 20010 to 55, 30 to 100, 40 to 200, 125 to 300, 200 to 4004675K2700000000
     

    Pressure-Regulating Valves for Steam

    Image of Product. Front orientation. Pressure-Regulating Valves. Pressure-Regulating Valves for Steam.
    Automatically reduce a high, variable inlet pressure in your steam system to a lower, stable outlet pressure. Adjust the outlet pressure within the range. These valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline.
    Internal Strainer—Internal strainers trap debris.
    Valves
    Repair Kits
    Inlet
    Outlet
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Pipe
    Size
    Location
    Pressure Adjustment
    Method
    End-to-End
    Lg.
    For Use
    With
    Temp. Range,
    ° F
    Choose an Outlet Pressure, psi
    Each
    Each
    NPT Female
     
    Cast Iron Body—Bronze Diaphragm and 420 Stainless Steel Seal
    1/2
    Side2501/2
    SideScrew3 5/8"Steam-20 to 4000 to 10, 10 to 50, 40 to 100, 100 to 2009796K3800000009796K96000000
    3/4
    Side2503/4
    SideScrew3 5/8"Steam-20 to 4000 to 10, 10 to 50, 40 to 100, 100 to 2009796K390000009796K9600000
    1
    Side2501
    SideScrew4 1/2"Steam-20 to 4000 to 10, 10 to 30, 30 to 50, 40 to 859796K910000009796K97000000
    1 1/4
    Side2501 1/4
    SideScrew4 1/2"Steam-20 to 4000 to 10, 10 to 30, 30 to 50, 40 to 859796K920000009796K97000000
    1 1/2
    Side2501 1/2
    SideScrew6 1/2"Steam-20 to 4000 to 10, 10 to 30, 30 to 50, 40 to 859796K930000009796K99000000
    2
    Side2502
    SideScrew6 1/2"Steam-20 to 4000 to 10, 10 to 30, 30 to 50, 40 to 859796K940000009796K99000000
     
    Cast Iron Body—Bronze Diaphragm and PTFE Seal with Internal Strainer
    1/4
    Side1501/4
    SideScrew3"Steam-20 to 4002 to 25, 20 to 60, 30 to 1004674K61000000———0
    3/8
    Side1503/8
    SideScrew3 7/8"Steam-20 to 4002 to 30, 20 to 70, 90 to 1504674K62000000———0
    1/2
    Side1501/2
    SideScrew4 1/2"Steam-20 to 4002 to 30, 10 to 50, 30 to 125, 50 to 1504674K630000004674K91000000
    3/4
    Side1503/4
    SideScrew5 1/8"Steam-20 to 4002 to 20, 10 to 35, 30 to 75, 50 to 110, 105 to 1504674K640000004674K92000000
    1
    Side1501
    SideScrew5 7/8"Steam-20 to 4002 to 20, 10 to 45, 20 to 60, 55 to 100, 90 to 1504674K650000004674K93000000
    1 1/4
    Side1501 1/4
    SideScrew6 3/4"Steam-20 to 4002 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 1504674K660000004674K94000000
    1 1/2
    Side1501 1/2
    SideScrew6 3/4"Steam-20 to 4002 to 15, 10 to 30, 20 to 50, 45 to 100, 90 to 1504674K670000004674K94000000
    2
    Side1502
    SideScrew9 1/4"Steam-20 to 4002 to 20, 10 to 60, 20 to 100, 90 to 1504674K68000000004674K95000000
     

    High-Accuracy Pressure-Regulating Valves for Steam

    Image of Product. Front orientation. Pressure-Regulating Valves. High-Accuracy Pressure-Regulating Valves for Steam.
    Control steam line pressure with ±1 psi accuracy. These valves automatically reduce a high, variable inlet pressure to a lower, stable outlet pressure. Adjust the outlet pressure within the range. Valves have a cast iron body that absorbs vibration from pressure changes to reduce wear and noise in your pipeline. They meet ANSI/FCI 70-2 Class IV for tight shut-off (max. leakage rate of 0.01%). Install 1/4 NPT male pipe (not included) between the control valve and your downstream steam line.
    Repair Kits—Repair kits (sold separately) include replacement seals, diaphragm, spring, and spring assembly.
    Valves
    Repair Kits
    Inlet
    Outlet
    Pipe
    Size
    Location
    Max. Pressure,
    psi
    Pipe
    Size
    Location
    Pressure Adjustment
    Method
    For Use
    With
    Temp. Range,
    ° F
    Specs. Met
    Choose an Outlet Pressure, psi
    Each
    Each
    NPT Female
     
    Cast Iron Body—301 Stainless Steel Diaphragm and 420 Stainless Steel Seal
    1/2
    Side2501/2
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K190000000009792K320000000
    3/4
    Side2503/4
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K21000000009792K33000000
    1
    Side2501
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K23000000009792K34000000
    1 1/4
    Side2501 1/4
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K25000000009792K35000000
    1 1/2
    Side2501 1/2
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K27000000009792K36000000
    2
    Side2502
    SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV3 to 20, 5 to 50, 10 to 100, 20 to 1509792K29000000009792K3700000000
     
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