Separate rusted galvanized pipe by heating with a torch, applying a plumber's candle, tapping with a hammer and turning with pipe wrenches. If necessary, place a length of pipe over the handle of the pipe wrench to increase torque.Continue Reading
Use a propane torch to heat the joint. The expansion and contraction helps to break through the rust.
While the joint is still hot enough to melt wax, rub a plumber's candle around the intersection of the two pipes. As the joint cools, it draws the wax into the joint, providing lubrication to reduce friction from the rust.
Hit the joint with a hammer to help loosen the rust.
Attach a pipe wrench to each of the two pipes that have rusted together. Hold the pipe stationary, and turn the fitting counterclockwise to loosen it. If the pipe refuses to budge, use a larger pipe wrench or apply more leverage by placing a length of pipe over the handle of the wrench. If the joint does not loosen, heat the joint and apply more wax. Continue the process until the joint breaks free.