For valves, not only will install and maintain, but also to operate.

1.Opening and closing the valve manually

Manual valves are the most widely used valves, its hand wheel or lever, in accordance with the normal human to design, taking into account.

Sealing surface of the strength and the necessary closing force. Therefore can not be used long lever or long wrench to board action. Some people are accustomed to using the wrench should be strictly careful not to force too much too fast, or easy to damage the sealing surfaces, or plates broken hand wheels, handles. Opening and closing valves, should force a smooth, non-impact. Impact of high pressure valves open and close certain parts of this impact has been considered and the general valve can not wait Gang. For the steam valve, open front, should be pre-heated, and the exclusion of condensate, open, should try to move slowly to avoid water hammer phenomenon. When the valve is fully open, the hand wheel rewind a little tight between the thread, so as not to loose damage. For rising stem valves, remember that when fully open and fully closed position of the valve stem, to avoid collision when fully open upper dead point. And easy to check whether it is normal when fully closed. If the valves do fall off, or plug seal embedded between larger debris, fully closed position of the valve stem will change.

Early use of pipeline , the internal dirt more, the valve can be parted , the use of high-speed flow of media , be washed away , and then gently close ( can not be closed quickly and shoved off , to prevent residual impurities pinch seal surface ) , turned on again , repeat several times , rinse the dirt , then put to work . Normally open valve sealing surface may be sticky dirt off using the above method should be washed clean, and then officially closed tightly .

Such as hand wheels, handles damaged or lost , immediately filled and can not be replaced with active wrench to avoid damage to the stem Quartet, the opening and closing ineffective , resulting in the production of an accident.

Some of the media , the valve is closed after cooling, the contraction of the valve member , the operator shall be at an appropriate time and then close again , so that the sealing surface without leaving slit , otherwise , the medium flowing from the slit high speed , it is easy sealing surface erosion .

Operation, such as the discovery operation is too strenuous , you should analyze the reasons. If the packing is too tight, may be appropriate to relax, such as stem skew shall notify personnel for repair . Some of the valve in the closed state, close to thermal expansion , resulting in open difficulties ; if they must turn at this point , you can loosen the bonnet threaded semi-circle to circle, remove the stem stress , and then board the handwheel .

2.Precautions

① Above 200 ℃ high temperature valve, since the installation is in normal temperature, and normal use, the temperature rises, the thermal expansion of the bolt, the gap to increase, it must be tightened again, called "hot tight", the operator should pay attention to this work, or prone to leakage.

② Cold weather, long-closed stop valve, water valve should be excluded. After the steam valve steam stop, we must exclude condensate. Valve end like plugs, it can be open drain.

③ Metallic valves, some hard and brittle, and some low intensity operation, the opening and closing force can not be too large, especially not to Meng Jin. Also note that the provision of free objects bump.

④ New valve is used, not too tight packing in order not to leak for the degree, in order to avoid too much pressure on the stem, accelerate wear, but hoist strenuous.

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