Why must spring cans be adjusted after they are put into service?

• A. Because the valves expand
• B. Because the water temperature changes
• C. Because the piping is insulated
• D. Because the lines become heavier when they are in service

Answer: (D)

Spring cans are part of pipe-support systems that use springs to hold the piping in the correct position. When the lines are cold and empty, the weight pressing on the spring is just the pipe itself. Once the system is in service, the lines fill with water and steam, so the actual weight increases. That added load changes how much the spring compresses and alters the line’s position. To keep the line at the proper height and prevent sagging, rubbing, or stress, the spring can must be adjusted after startup to account for the heavier, in-service load. The idea is about how the load changes when the line becomes full during operation, not about valve expansion, insulation, or temperature alone.