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NIBCO Sweat Fitting Union: 1/4 in CTS x 1/4 in CTS, Cup x Cup, Wrot Copper (MPN 633W 1/4) - Wrot Copper Tube Fittings
NIBCOWrot Copper Tube Fittings

NIBCO Sweat Fitting Union: 1/4 in CTS x 1/4 in CTS, Cup x Cup, Wrot Copper (MPN 633W 1/4)

SKU 3G-OTH-472131

Brand
NIBCO
Item
Sweat Fitting Union: 1/4 in CTS x 1/4 in CTS, Cup x Cup, Wrot Copper
Category
Wrot Copper Tube Fittings
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Technical Specifications

NIBCO
Manufacturer Part Number
633W 1/4
Type
Cup x Cup, Wrot Copper
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NIBCO Products
3G Electric (S) Pte. Ltd. — Singapore

Frequently Asked Questions

What is a NIBCO sweat fitting union used for?

A NIBCO sweat fitting union connects two copper pipes in a way that allows disassembly without cutting the line. It is used in plumbing, HVAC, and industrial piping systems where maintenance or component replacement is needed. The cup x cup design accepts 1/4 in CTS tubing on both ends.

What are the specifications of the NIBCO 633W 1/4 union?

The NIBCO 633W 1/4 is a wrot copper sweat fitting union with cup x cup connections for 1/4 in CTS copper tubing. It is designed for soldered installation and provides a reliable, leak-resistant joint in low-pressure plumbing and heating applications. The manufacturer part number is 633W 1/4.

Where to buy NIBCO sweat fitting unions worldwide?

3G Electric supplies NIBCO sweat fitting unions worldwide. As a global industrial solutions provider, we handle logistics, customs clearance, and delivery to your location. Contact us to order the NIBCO 633W 1/4 union or other wrot copper fittings for your project.

How to install a NIBCO sweat fitting union?

To install a NIBCO sweat fitting union, clean and flux the 1/4 in CTS copper tube ends and the cup interiors. Assemble the union, apply heat evenly with a torch, and feed solder into the joint until it flows fully. Allow to cool before pressurizing. Always follow local plumbing codes and use proper safety gear.

Used in

Common applications for NIBCO
HVAC systems — NIBCO bronze ball valves (T58570UL series) for isolation and control in chilled water loops
Water treatment plants — NIBCO bronze gate valves (T29 series) for shut-off in filtration and distribution lines
Industrial burner systems — NIBCO brass ball valves (GB2A series) for fuel oil or gas supply lines
Chemical processing — NIBCO bronze ball valves with locking lever (T58570LL series) for safety-critical flow control
Steam systems — NIBCO bronze globe valves for throttling in low-pressure steam applications
General plumbing — NIBCO bronze ball valves (S58570 series) with sweat connections for copper piping in commercial buildings

NIBCO Products

3G Electric supplies NIBCO wrot copper tube fittings. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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