How to Install a Dresser Coupling on Rusty Pipes
A Dresser coupling -- made by the Dresser Company -- is a compression coupling you can use to repair galvanized steel and other metal pipes. They can connect pipes with or without threads and are especially useful when threads have rusted and become unusable. A Dresser coupling differs from a conventional compression coupling by having bolts and rings to secure the two gaskets inside it that provide the seal. If your pipes have rusty threads or no threads, use a Style 38 coupling. If the gap between the pipes is greater than 3 inches but less than 14 inches, use a Style 40 coupling, which has an elongated body.
1
Slide one of the coupling rings onto the end of one of the pipes you are joining with its smooth side facing out. Then slide the resilient gasket on with the tapered side facing out. Put the other ring and gasket on the other pipe in the same way.
2
Move the rings and gaskets back far enough to allow you to fit the body of the coupling between them. Each ring and gasket should be the same distance from the end of the pipe.
3
Line up the bolt holes on the rings and slip one of the bolts that came with the coupling through each opposing pair of holes. Screw a nut onto each bolt.
4
Hand-tighten the bolts, and then use a wrench to turn each one through one turn before moving onto the next one. Continue tightening in this way until all the nuts are secured. Hold the body of the coupling steady with adjustable pliers to prevent it from moving while you tighten the nuts.
References
Tips
- If the pipes you are joining have different diameters, use a Style 62 reducing coupling.
- The ends of the pipes should be inserted at least an inch into the coupling body. The deeper you can insert them, the more secure the seal will be.
- Use a Dresser style 360 repair clamp to stop a leak in a rusty pipe. To use this clamp, one of the ends of the pipe must be free. Slide the clamp along the pipe until it covers the leak, then tighten the nuts connected to it with a wrench or screwdriver to make a watertight seal.
Warnings
- Support pipes that are joined with a Dresser coupling so they can't move, because lateral motion can break the compression seal. If you're joining vertical pipes, you must support the bottom one, or it can work its way out of the coupling.
Writer Bio
Chris Deziel has a bachelor's degree in physics and a master's degree in humanities. Besides having an abiding interest in popular science, Deziel has been active in the building and home design trades since 1975. As a landscape builder, he helped establish two gardening companies.