In the process pipeline or equipment, the installation of the valve due to the nature of the media, the use of the environment, the frequency of operation and product quality and other factors, often a variety of failures, and sometimes not only affect the production, but also bring disaster, therefore, should strengthen protection, timely Troubleshoot Such as: Failure phenomenon: tight seal. Failure causes: 1, seat and valve body with less stringent; 2, close the valve improper use of auxiliary tools, off too tight. Treatment: 1, repair seals; 2, appropriate force, do not use the force lever switch valve.