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    22 Products

    Low-Pressure Iron and Steel Threaded Pipe Fittings

    Use these fittings for low-pressure applications in noncorrosive environments.
    Square-Drive Plugs
    Image of Product. Male. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Fittings, Square-Drive Plugs, Threaded Fitting Connection, Male.

    Male

    Pipe
    Size
    Construction
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    NPT Male
    3 1/2
    Hollow125
    Iron175 psi @ 72° F125 psi @ 350° F44605K707000000
     
    External-Square-Drive Plugs
    Image of Product. Male. Front orientation. Pipe and Fittings. Low-Pressure Iron and Steel Threaded Pipe Fittings, External-Square-Drive Plugs, Threaded Fitting Connection, Male, Square Body.

    Male

    Pipe
    Size
    Construction
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Each
    NPT Male
    3 1/2
    Hollow125
    SquareIron175 psi @ 72° F125 psi @ 350° F44605K703000000
     

    Wing-Nut Expansion Plugs

    Image of Product. Front orientation. Expansion Plugs. Wing-Nut Expansion Plugs, Style A.

    Style A

    Twist the wing nut on these plugs to expand the seal and close off pipe openings.
    Style A—Style A aren’t recommended for pressure testing, so they’re often used as a dust cover.
    Stainless Steel Plate—Plugs with a stainless steel plate have excellent corrosion resistance.
    Maximum Air Back Pressure—Maximum air back pressure is the amount of pressure a plug can withstand without moving.
    Maximum Water Back Pressure—Maximum water back pressure refers to the pressure resulting from the height of the water above the plug.
    For
    Pipe
    Max. Back
    Pressure
    Size
    ID
    Air,
    psi
    Water, ft.
    of head
    Overall
    Ht.
    Temp. Range,
    ° F
    Seal
    Material
    Each
    Style A
     
    Stainless Steel Plate
    3 1/2
    3.44" to 3.60"5122 15/16"0 to 175Neoprene
    2613K73000000
     

    Hollow Tapered Plugs

    Image of Product. Front orientation. Contains Annotated. Protective Plugs. Hollow Tapered Plugs.
    A hollow construction makes these plugs extra flexible, so they compress for easy installation and a snug fit. The tapered profile fits a range of hole diameters. If you flip the plug over, it can be used as a cap.
    Polyethylene—Convenient and economical. Instead of cleaning and reusing, just toss and grab a new plug.
    For ID
    For Pipe
    Size
    Ht.
    Max. Temp.,
    ° F
    Color
    Flange
    Dia.
    Pkg.
    Qty.
    Pkg.
    Polyethylene
    3.47" to 3.6"3 1/2
    3/4"150Red3 7/8"104491K9400000
    3.79" to 3.92"3 1/2
    3/4"150Red4 1/8"254491K10400000
     

    Hex-Nut Expansion Plugs

    Image of Product. Front orientation. Expansion Plugs. Hex-Nut Expansion Plugs, Style B.

    Style B

    Tighten the nut on these plugs to expand the seal and close off pipe openings.
    Stainless Steel Plate—Plugs with a stainless steel plate have excellent corrosion resistance.
    Maximum Air Back Pressure—Maximum air back pressure is the amount of pressure a plug can withstand without moving.
    Maximum Water Back Pressure—Maximum water back pressure refers to the pressure resulting from the height of the water above the plug.
    For
    Pipe
    Max. Back
    Pressure
    Size
    ID
    Air,
    psi
    Water, ft.
    of head
    Overall
    Ht.
    Temp. Range,
    ° F
    Seal
    Material
    Each
    Style B
     
    Stainless Steel Plate
    3 1/2
    3.44" to 3.60"5123 1/16"-40 to 250Neoprene
    2599K55000000
     

    Brass and Bronze Threaded Cleanout Plugs

    Image of Product. Raised. Front orientation. Pipe and Fittings. Brass and Bronze Threaded Cleanout Plugs.

    Raised

    Image of Product. Recessed. Front orientation. Pipe and Fittings. Brass and Bronze Threaded Cleanout Plugs.

    Recessed

    Close off your drain cleanout pipe with these threaded plugs. Note: If you do not know your pipe size, measure the OD of your existing cleanout plug or the ID of your cleanout fitting and match to the value listed.
    To prevent leaks in threaded connections, apply a sealant to the male threads. Threaded connections can be taken apart as needed for maintenance and repair. For metal threads, use PTFE tape. For plastic threads, apply a non-hardening, plastic-compatible sealant. Tape or sealants with PTFE are not recommended for plastic-to-plastic connections. When making a threaded connection be careful not to overtighten the threads. To prevent cracks and leaks, finger tighten the fitting, then wrench-tighten one to two turns.
    Recessed
    Raised
    Cleanout Plug
    OD/Fitting ID
    For Pipe
    Size
    Thread
    Type
    Material
    Each
    Each
    3 31/32"3 1/2
    NPT
    Brass2400K560000002400K7600000
    Plug Wrenches

    Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings

    The galvanized finish on these fittings provides fair corrosion resistance. Fittings are for use in low-pressure applications.
    External-Square-Drive Plugs
    Image of Product. Front orientation. Pipe and Fittings. Low-Pressure Galvanized Iron and Steel Threaded Pipe Fittings, External-Square-Drive Plugs, Threaded Fitting Connection, Male.

    Male, Threaded

    Fitting

    Connection

    Pipe
    Size
    Construction
    Pressure
    Class
    Body
    Shape
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    NPT Male
    3 1/2
    Hollow125
    SquareGalvanized Iron125 psi @ 72° F125 psi @ 350° FUL Listed
    4638K936000000
     

    T-Handle Expansion Plugs

    Image of Product. Front orientation. Expansion Plugs. T-Handle Expansion Plugs.
    Twist the easy-grip T-handle on these plugs to expand the seal and close off pipe openings.
    Zinc-Plated Steel Plate—Plugs with a zinc-plated steel plate have fair corrosion resistance.
    Stainless Steel Plate—Plugs with a stainless steel plate have excellent corrosion resistance.
    Maximum Air Back Pressure—Maximum air back pressure is the amount of pressure a plug can withstand without moving.
    Maximum Water Back Pressure—Maximum water back pressure refers to the pressure resulting from the height of the water above the plug.
    For
    Pipe
    Max. Back
    Pressure
    Brass Handle
    Stainless
    Steel Handle
    Size
    ID
    Air,
    psi
    Water, ft.
    of head
    Overall
    Ht.
    Temp. Range,
    ° F
    Seal
    Material
    Each
    Each
     
    Zinc-Plated Steel Plate
    3 1/2
    3.44" to 3.60"5123 15/16"-40 to 250Neoprene
    2527K26000000———0
     
    Stainless Steel Plate
    3 1/2
    3.44" to 3.60"5123 15/16"-40 to 250Neoprene
    ———02908K31000000
     

    ABS Threaded Cleanout Plugs

    Image of Product. Recessed. Front orientation. Pipe and Fittings. ABS Threaded Cleanout Plugs.

    Recessed

    Close off your drain cleanout pipe with these threaded plugs. Note: If you do not know your pipe size, measure the OD of your existing cleanout plug or the ID of your cleanout fitting and match to the value listed.
    To prevent leaks in threaded connections, apply a sealant to the male threads. Threaded connections can be taken apart as needed for maintenance and repair. For metal threads, use PTFE tape. For plastic threads, apply a non-hardening, plastic-compatible sealant. Tape or sealants with PTFE are not recommended for plastic-to-plastic connections. When making a threaded connection be careful not to overtighten the threads. To prevent cracks and leaks, finger tighten the fitting, then wrench-tighten one to two turns.
    Recessed
    Cleanout Plug
    OD/Fitting ID
    For Pipe
    Size
    Thread
    Type
    Material
    Each
    3 31/32"3 1/2
    NPT
    ABS9359T2500000
    Plug Wrenches

    Tapered Caps

    Image of Product. Front orientation. Protective Caps. Tapered Caps.
    Don't worry about having the exact size you need on hand. These caps are shaped to fit a range of ODs—just keep pushing on until they're snug. Because they make less contact with the parts they cover, they’re easier to remove than straight caps. In a pinch, you can flip tapered caps over and use them as plugs.
    Polyethylene—Convenient and economical, these flexible caps are one and done. Instead of cleaning and reusing, just toss and grab a new cap.
    For OD
    For Pipe
    Size
    Inside
    Ht.
    Flexibility
    Max. Temp.,
    ° F
    Color
    Pkg.
    Qty.
    Pkg.
    Polyethylene
    3.71" to 3.84"3 1/2
    3/4"Flexible150Red254491K152000000
    3.94" to 4.07"3 1/2
    3/4"Flexible150Red254491K12700000
     

    FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges

    FM-approved for fire protection applications, these flanges are cast iron, so they're brittle and can be quickly opened by hitting them with a sledge hammer. Bolt them together with a gasket (not included) to create an access point within a low-pressure pipe line. All are cap flanges, which are also known as blind flanges. Use them in noncorrosive environments.
    Cast Blind Flanges
    Image of Product. Front. Front orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges.
    Image of Product. Back. Back orientation. Pipe and Fittings. FM-Approved Low-Pressure Iron and Steel Unthreaded Pipe Flanges.

    Front

    Back

    Cast flanges are also called MSS flanges.
    Bolt
    Hole
    Pipe
    Size
    Flanged Connection
    Surface
    Flange
    OD
    For Bolt
    Dia.
    Dia.
    No.
    Of
    Bolt Circle
    Dia.
    Pressure
    Class
    Material
    Max. Pressure
    @ Temp.
    Max. Steam Pressure
    @ Temp.
    Certification
    Each
    Flanged
    3 1/2
    Flat8 1/2"5/8"3/4"87"125
    Cast Iron200 psi @ 72° F165 psi @ 300° FFM Approved
    4824N160000000
     

    Quick-Snap Expansion Plugs

    Image of Product. Front orientation. Expansion Plugs. Quick-Snap Expansion Plugs.
    Turn the cam handle to expand the seal, then snap the handle down to hold it in place and close off pipe openings.
    Zinc-Plated Steel Plate—Plugs with a zinc-plated steel plate have fair corrosion resistance.
    Stainless Steel Plate—Plugs with a stainless steel plate have excellent corrosion resistance.
    Maximum Air Back Pressure—Maximum air back pressure is the amount of pressure a plug can withstand without moving.
    Maximum Water Back Pressure—Maximum water back pressure refers to the pressure resulting from the height of the water above the plug.
    For
    Pipe
    Max. Back
    Pressure
    Brass Handle
    Stainless
    Steel Handle
    Size
    ID
    Air,
    psi
    Water, ft.
    of head
    Overall
    Ht.
    Temp. Range,
    ° F
    Seal
    Material
    Each
    Each
     
    Zinc-Plated Steel Plate
    3 1/2
    3.38" to 3.60"5122 5/16"-40 to 250Neoprene
    2598K37000000———0
     
    Stainless Steel Plate
    3 1/2
    3.38" to 3.60"5122 5/16"-40 to 250Neoprene
    ———09191T63000000
     

    Floor Drain Trap Seals

    Image of Product. Front orientation. Floor Drain Trap Seals.
    Stop sewer gases from escaping through your floor drain if the P-trap dries out. Similar to a check valve, they allow liquid to drain but won’t let gases back up. They’re especially useful in infrequently used drains. To install, remove the strainer from your drain and place these seals in the opening. They have fins that grip the inside of the drain and a top ring to keep them in place. After putting the strainer back, pour water through the drain to fill the P-trap.
    For Pipe
    Size
    ID
    OD
    Overall
    Ht.
    Each
    Plastic/Rubber
    3 1/2
    2 5/8"3 3/4"2 5/8"6344N13000000
     

    Metal Round Caps

    Image of Product. Front orientation. Protective Caps. Metal Round Caps.
    Tougher than plastic and rubber caps for best protection from impact and wear. These caps cover pipe ends to prevent damage and keep out dust and debris during shipping and storage.
    Steel—The strongest caps, but moisture can cause them to rust.
    Aluminum—Use aluminum caps instead of steel to prevent corrosion from spreading to aluminum pipe and tubing.
    18-8 Stainless Steel—Our most corrosion-resistant caps for parts exposed to moisture and the outdoors.
    Steel
    Aluminum
    18-8
    Stainless Steel
    For
    OD
    For Pipe
    Size
    Inside
    Ht.
    Flexibility
    Max.
    Temp.
    Each
    Each
    Each
    4"3 1/2
    1 1/2"RigidNot Rated9275K68000009275K350000009275K443000000
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