Precautions in Vacuum Valve Procedure

Keep away from valve staggering, incorrect closing, missing opening and lacking closing. The operator shall evidently comprehend the operate of every single valve and its situation in the method pipeline to steer clear of misoperation, or it may cause materials working, mixing, force holding and other accidents. For example, steam purging is carried out before the commence of a refinery products, and a vent valve is leaked soon after purging. As a consequence, 370 ℃ large-temperature oil slurry is discharged from the vent valve for the duration of the start off of the project, triggering a fire, and the gear is shut down.

When the temperature is beneath ℃, the valve that is out of services shall be antifreezed first, and the plug at the bottom of the valve shall be opened in time to discharge the condensed water inside of. The valves that can't be cleaned and operated continually shall be stored warm.

For valves running at large temperature, when the temperature rises over two hundred ℃, the bolts are heated and prolonged, which is straightforward to make the valve seal not tight. When vacuumfittings , the bolts shall be “hot tight”. When sizzling limited, it is not appropriate to carry out in the entirely shut situation of the valve. In order to avoid the valve stem from becoming jacked and difficult to open once more.

When the valve leaks, the leakage situation and cause shall be recognized 1st. Generally, the leakage is divided into two kinds: leakage at the packing, leakage at the valve go over, valve physique and leakage at the sealing area or cloth in accordance to the external structure. The operator shall properly judge the leakage, and manage the problems that can be solved by himself in time, and the problems that can not be solved by him in time.

The packing gland of the valve need to not be pressed also tightly. It is greater that the valve rod can rotate sensitively. If it is pressed way too tightly, the friction of the valve rod will be increased and the running torque will be increased. In the course of valve procedure, it is normally not authorized to exchange or include packing with stress at will, otherwise, leakage of medium could cause pitfalls.