The typical positions of pipeline include flange, pipe, elbow and three-way pipe. At present, the method to deal with the leakage of pipeline is the technique of leakage blocking in pressure with sealant. The important part of the technique of leakage blocking in pressure with sealant is leak clamp. According to the condition of leakage, temperature and pressure of medium, the leak clamp should be carefully designed. The leaking causes on pipeline are simply analyzed.The leak clamps used in different leakage parts, including flange,pipe,elbow and three-way pipe are also introduced.