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    39 Products

    Flange-Mount Pressure-Relief Discs

    Install these discs within the bolt circle of ANSI Class 150 flanges. They break open at the burst pressure to allow unrestricted flow. All are for one-time use. Discs are made of resin-filled graphite for resistance to temperature and pressure fluctuations as well as corrosive liquids and gases. They include two gaskets for installation between flanges.
    Pressure-Relief Discs
    Image of Product. Front orientation. Pressure-Relief Discs. Flange-Mount Pressure-Relief Discs.
    Operating Ratio—Operating ratio is the ratio between the normal operating pressure and the burst pressure. Exceeding the operating ratio decreases the service life of the disc. For example, a disc with a burst pressure of 100 psi and an operating ratio of 80% should not be used in a system with an operating pressure greater than 80 psi.
    Pipe
    Size
    For Flange
    ANSI Class
    OD
    Thk.
    Operating
    Ratio
    Temp. Range,
    ° F
    Gasket
    Material
    Valve Type
    Choose a Burst Pressure, psi
    Each
    Graphite Body—Resin-Filled Graphite Disc
    1
    150
    2 1/2"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    ,
    250
    000000000000000
    1 1/2
    150
    3 1/4"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    ,
    250
    00000000000000
    2
    150
    4"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    ,
    250
    00000000000000
    3
    150
    5 1/4"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    ,
    250
    00000000000000
    4
    150
    6 3/4"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    ,
    250
    00000000000000
    6
    150
    8 5/8"1 1/8"80%-20 to 300Neoprene
    Rupture Disc
    20
    ,
    25
    ,
    30
    ,
    40
    ,
    50
    ,
    60
    ,
    75
    ,
    100
    ,
    125
    ,
    150
    ,
    175
    ,
    200
    00000000000000
     
    Vacuum Rated Pressure-Relief Discs
    Image of Product. Front orientation. Pressure-Relief Discs. Flange-Mount Pressure-Relief Discs, Vacuum Rated Pressure-Relief Discs .
    Vacuum-rated discs have supports to resist rupture caused by vacuum.
    Operating Ratio—Operating ratio is the ratio between the normal operating pressure and the burst pressure. Exceeding the operating ratio decreases the service life of the disc. For example, a disc with a burst pressure of 100 psi and an operating ratio of 80% should not be used in a system with an operating pressure greater than 80 psi.
    Pipe
    Size
    For Flange
    ANSI Class
    OD
    Thk.
    Max. Vacuum,
    in. Hg
    Operating
    Ratio
    Temp. Range,
    ° F
    Gasket
    Material
    Valve Type
    Choose a Burst
    Pressure, psi
    Each
    Graphite Body—Resin-Filled Graphite Disc
    1
    150
    2 1/2"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc15000000000000000
    1 1/2
    150
    3 1/4"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc
    10
    ,
    15
    00000000000000
    2
    150
    4"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc
    5
    ,
    10
    ,
    15
    00000000000000
    3
    150
    5 1/4"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc
    5
    ,
    10
    ,
    15
    00000000000000
    4
    150
    6 3/4"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc
    5
    ,
    10
    ,
    15
    00000000000000
    6
    150
    8 5/8"1 1/8"29.9280%-20 to 300Neoprene
    Rupture Disc
    5
    ,
    10
    ,
    15
    00000000000000
     

    Remote-Discharge Threaded Pressure-Relief Discs

    Image of Product. Front orientation. Pressure-Relief Discs. Remote-Discharge Threaded Pressure-Relief Discs.
    Instead of exhausting discharge directly, these discs have a threaded relief port for attaching a drain line to direct discharge away from your work environment. They are for installation in pipelines and tanks. Discs break open at the burst pressure to allow unrestricted flow. All are for one-time use.
    316 Stainless Steel Disc—316 stainless steel discs are more corrosion resistant than nickel discs.
    Operating Ratio—Operating ratio is the ratio between the normal operating pressure and the burst pressure. Exceeding the operating ratio decreases the service life of the disc. For example, a disc with a burst pressure of 100 psi and an operating ratio of 80% should not be used in a system with an operating pressure greater than 80 psi.
    Inlet
    Relief
    Port
    Burst Pressure,
    psi
    Pipe
    Size
    Location
    Pipe
    Size
    Location
    Operating
    Ratio
    Temp. Range,
    ° F
    End-to-End
    Lg.
    Valve Type
    Each
    NPT Male Inlet and Pipe Relief Port
     
    Brass Body—Nickel Disc
    1003/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc000000000000000
    1001/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
    1253/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    1251/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
    1503/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    1501/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
     
    Brass Body—316 Stainless Steel Disc
    2003/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    2001/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
    2503/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    2501/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
    5003/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    5001/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
    7003/8
    Side1/2
    Side80%-50 to 5002 1/8"Rupture Disc00000000000000
    7001/2
    Side1/2
    Side80%-50 to 5002 1/4"Rupture Disc00000000000000
     

    Threaded Pressure-Relief Discs

    Image of Product. Front orientation. Pressure-Relief Discs. Threaded Pressure-Relief Discs.
    These valves have a vented relief port to exhaust discharge directly. They are for installation in pipelines and tanks. All break open at the burst pressure to allow unrestricted flow. Discs are for one-time use.
    316 Stainless Steel Disc—316 stainless steel discs are more corrosion resistant than nickel discs.
    Operating Ratio—Operating ratio is the ratio between the normal operating pressure and the burst pressure. Exceeding the operating ratio decreases the service life of the disc. For example, a disc with a burst pressure of 100 psi and an operating ratio of 80% should not be used in a system with an operating pressure greater than 80 psi.
    Inlet
    Burst Pressure,
    psi
    Pipe
    Size
    Location
    Relief Port
    Location
    Operating
    Ratio
    Temp. Range,
    ° F
    Overall
    Ht.
    Valve Type
    Each
    NPT Male Inlet and Vent Relief Port
     
    Brass Body—Nickel Disc
    1001/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc000000000000000
    1251/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
    1501/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
     
    Brass Body—316 Stainless Steel Disc
    2001/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
    2501/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
    5001/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
    7001/4
    BottomSide80%-50 to 5001 5/8"Rupture Disc00000000000000
     

    Heat-Activated Threaded Pressure-Relief Discs

    Image of Product. Front orientation. Pressure-Relief Discs. Heat-Activated Threaded Pressure-Relief Discs.
    Also known as fusible plugs, these discs have a metal core that melts at a set temperature to exhaust discharge directly and allow unrestricted flow. Install these one-time-use discs in pipelines and tanks.
    500 psi Maximum Pressure—These discs should not be used in a system with an operating pressure greater than 500 psi.
    Maximum Operating Temperature—Exceeding the maximum operating temperature decreases service life and may cause the disc to open below its melting temperature.
    Inlet
    Pipe
    Size
    Location
    Relief Port
    Location
    Max. Pressure,
    psi
    Max. Operating
    Temp., ° F
    Overall
    Ht.
    Disc Material
    Valve Type
    Each
    NPT Male Inlet and Vent Relief Port
     
    Brass Body—165° F Melting Temperature
    1/4
    BottomTop5001003/4"Bismuth, Cadmium, Lead, TinRupture Disc0000000000000
    3/8
    BottomTop5001003/4"Bismuth, Cadmium, Lead, TinRupture Disc000000000000
    1/2
    BottomTop5001007/8"Bismuth, Cadmium, Lead, TinRupture Disc000000000000
     
    Brass Body—212° F Melting Temperature
    1/4
    BottomTop5001503/4"Bismuth, Lead, TinRupture Disc000000000000
    3/8
    BottomTop5001503/4"Bismuth, Lead, TinRupture Disc000000000000
    1/2
    BottomTop5001507/8"Bismuth, Lead, TinRupture Disc000000000000
     
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