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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 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		00000000000000
    1/2
    		081/2
    		082 3/16"1 7/16"6 3/16"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		0000000000000
    3/4
    		123/4
    		122 11/16"1 11/16"6 15/16"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		0000000000000
    1
    		161
    		163 5/16"2 1/16"8 1/4"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		0000000000000
    1 1/4
    		201 1/4
    		203 13/16"2 1/2"9 9/16"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		0000000000000
    1 1/2
    		241 1/2
    		244 1/8"2 7/8"11 1/16"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    300 to 500
    		0000000000000
    2
    		322
    		324 5/8"3 1/4"13"-20 to 400
    3 to 10
    ,
    7 to 35
    ,
    30 to 100
    ,
    60 to 175
    ,
    150 to 350
    ,
    250 to 600
    		0000000000000
     

    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 Safety
    2
    ,
    4
    ,
    6
    ,
    8
    ,
    10
    ,
    12
    ,
    14
    		00000000000000
    2 1/2
    		Bottom602 1/2
    		Side90° Elbow8"Air, Inert Gas-20 to 406T-HandlePop Safety
    2
    ,
    4
    ,
    6
    ,
    8
    ,
    10
    ,
    12
    ,
    14
    		0000000000000
    3
    		Bottom603
    		Side90° Elbow9"Air, Inert Gas-20 to 406T-HandlePop Safety
    2
    ,
    4
    ,
    6
    ,
    8
    ,
    10
    ,
    12
    ,
    14
    		000000000000000
     

    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 180
    2 to 25
    ,
    20 to 60
    		00000000000000
    3/8
    		Side2003/8
    		SideScrew3 7/8"Water, Oil, Air, Inert Gas32 to 180
    2 to 30
    ,
    20 to 70
    ,
    40 to 110
    ,
    90 to 150
    		0000000000000
    1/2
    		Side2001/2
    		SideScrew4 1/2"Water, Oil, Air, Inert Gas32 to 180
    2 to 30
    ,
    10 to 50
    ,
    30 to 125
    ,
    50 to 125
    		0000000000000
    3/4
    		Side2003/4
    		SideScrew5 1/8"Water, Oil, Air, Inert Gas32 to 180
    2 to 20
    ,
    10 to 35
    ,
    30 to 75
    ,
    50 to 110
    ,
    105 to 125
    		0000000000000
    1
    		Side2001
    		SideScrew5 7/8"Water, Oil, Air, Inert Gas32 to 180
    2 to 20
    ,
    10 to 45
    ,
    20 to 60
    ,
    55 to 100
    ,
    90 to 125
    		0000000000000
    1 1/4
    		Side2001 1/4
    		SideScrew6 3/4"Water, Oil, Air, Inert Gas32 to 180
    2 to 15
    ,
    10 to 30
    ,
    20 to 50
    ,
    45 to 100
    ,
    90 to 150
    		0000000000000
    1 1/2
    		Side2001 1/2
    		SideScrew6 3/4"Water, Oil, Air, Inert Gas32 to 180
    2 to 15
    ,
    10 to 30
    ,
    20 to 50
    ,
    45 to 100
    ,
    90 to 125
    		0000000000000
    2
    		Side2002
    		SideScrew9 1/4"Water, Oil, Air, Inert Gas32 to 180
    2 to 20
    ,
    10 to 60
    ,
    20 to 100
    ,
    90 to 125
    		0000000000000
     
    Cast Iron Body—Fluoroelastomer Diaphragm and 420 Stainless Steel Seal
    3/8
    		Side2503/8
    		SideScrew4 1/4"Water, Oil, Air, Inert Gas32 to 300
    0 to 10
    ,
    10 to 50
    ,
    40 to 100
    ,
    100 to 200
    		0000000000000
    1/2
    		Side2501/2
    		SideScrew3 5/8"Water, Oil, Air, Inert Gas32 to 300
    0 to 10
    ,
    10 to 50
    ,
    40 to 100
    ,
    100 to 200
    		0000000000000
    3/4
    		Side2503/4
    		SideScrew3 5/8"Water, Oil, Air, Inert Gas32 to 300
    0 to 10
    ,
    10 to 50
    ,
    40 to 100
    ,
    100 to 200
    		0000000000000
    1
    		Side2501
    		SideScrew4 1/2"Water, Oil, Air, Inert Gas32 to 300
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		0000000000000
    2
    		Side2502
    		SideScrew6 1/2"Water, Oil, Air, Inert Gas32 to 300
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		0000000000000
     

    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 Fluid
    100 to 1,000
    ,
    500 to 2,000
    ,
    1,000 to 3,000
    		0000000000000
     

    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
    ,
    60
    		00000000000000
    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
    ,
    60
    		0000000000000
    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
    ,
    60
    		000000000000000
     

    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 200
    0 to 25
    ,
    5 to 50
    ,
    30 to 100
    ,
    75 to 175
    ,
    150 to 400
    		00000000000000
    1 1/4
    		Side4001 1/4
    		SideScrew1 1/4
    		Bottom4 1/4"Water, Oil-40 to 200
    20 to 85
    ,
    40 to 125
    ,
    50 to 230
    ,
    175 to 380
    ,
    300 to 400
    		000000000000000
    1 1/2
    		Side4001 1/2
    		SideScrew1 1/2
    		Bottom5"Water, Oil-40 to 200
    10 to 55
    ,
    30 to 100
    ,
    40 to 200
    ,
    125 to 300
    ,
    200 to 400
    		000000000000000
    2
    		Side4002
    		SideScrew2
    		Bottom5"Water, Oil-40 to 200
    10 to 55
    ,
    30 to 100
    ,
    40 to 200
    ,
    125 to 300
    ,
    200 to 400
    		000000000000000
     

    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 400
    0 to 10
    ,
    10 to 50
    ,
    40 to 100
    ,
    100 to 200
    		000000000000000000000000000
    3/4
    		Side2503/4
    		SideScrew3 5/8"Steam-20 to 400
    0 to 10
    ,
    10 to 50
    ,
    40 to 100
    ,
    100 to 200
    		0000000000000000000000000
    1
    		Side2501
    		SideScrew4 1/2"Steam-20 to 400
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		00000000000000000000000000
    1 1/4
    		Side2501 1/4
    		SideScrew4 1/2"Steam-20 to 400
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		00000000000000000000000000
    1 1/2
    		Side2501 1/2
    		SideScrew6 1/2"Steam-20 to 400
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		00000000000000000000000000
    2
    		Side2502
    		SideScrew6 1/2"Steam-20 to 400
    0 to 10
    ,
    10 to 30
    ,
    30 to 50
    ,
    40 to 85
    		00000000000000000000000000
     
    Cast Iron Body—Bronze Diaphragm and PTFE Seal with Internal Strainer
    1/4
    		Side1501/4
    		SideScrew3"Steam-20 to 400
    2 to 25
    ,
    20 to 60
    ,
    30 to 100
    		0000000000000———0
    3/8
    		Side1503/8
    		SideScrew3 7/8"Steam-20 to 400
    2 to 30
    ,
    20 to 70
    ,
    90 to 150
    		0000000000000———0
    1/2
    		Side1501/2
    		SideScrew4 1/2"Steam-20 to 400
    2 to 30
    ,
    10 to 50
    ,
    30 to 125
    ,
    50 to 150
    		00000000000000000000000000
    3/4
    		Side1503/4
    		SideScrew5 1/8"Steam-20 to 400
    2 to 20
    ,
    10 to 35
    ,
    30 to 75
    ,
    50 to 110
    ,
    105 to 150
    		00000000000000000000000000
    1
    		Side1501
    		SideScrew5 7/8"Steam-20 to 400
    2 to 20
    ,
    10 to 45
    ,
    20 to 60
    ,
    55 to 100
    ,
    90 to 150
    		00000000000000000000000000
    1 1/4
    		Side1501 1/4
    		SideScrew6 3/4"Steam-20 to 400
    2 to 15
    ,
    10 to 30
    ,
    20 to 50
    ,
    45 to 100
    ,
    90 to 150
    		00000000000000000000000000
    1 1/2
    		Side1501 1/2
    		SideScrew6 3/4"Steam-20 to 400
    2 to 15
    ,
    10 to 30
    ,
    20 to 50
    ,
    45 to 100
    ,
    90 to 150
    		00000000000000000000000000
    2
    		Side1502
    		SideScrew9 1/4"Steam-20 to 400
    2 to 20
    ,
    10 to 60
    ,
    20 to 100
    ,
    90 to 150
    		00000000000000000000000000
     

    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 IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		000000000000000000000000000000
    3/4
    		Side2503/4
    		SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		0000000000000000000000000000
    1
    		Side2501
    		SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		0000000000000000000000000000
    1 1/4
    		Side2501 1/4
    		SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		0000000000000000000000000000
    1 1/2
    		Side2501 1/2
    		SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		0000000000000000000000000000
    2
    		Side2502
    		SideScrewSteam40 to 450ANSI/FCI 70-2 Class IV
    3 to 20
    ,
    5 to 50
    ,
    10 to 100
    ,
    20 to 150
    		000000000000000000000000000000
     
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