Pneumatic control valve movement is normal, but can't afford to adjust action, how to return a responsibility

With 'the action of pneumatic control valve is normal, but can't afford to adjust action' fault as an example in this paper, the maintenance plan: vinyl chloride workshop in a chemical plant, using the valve for sic eleven factory single-seat pneumatic control valve. This production line with annual capacity of 100000 tons of plastic particles, the compression of vinyl chloride workshop, transformation, fractionation section has two sets of production line. In addition to the compression, transformation and fractionation section are extensive use of pneumatic control valve, a pneumatic - valve working environment is completely different, and each tube is usually only a pneumatic control valve on the road, next to some of the pneumatic control valve with by-pass, can by manual control valve. If pneumatic - valve malfunction, you can open the bypass valve, to ensure normal production. So, before the overhaul, carefully analyze the failure reasons of pneumatic control valve, making perfect maintenance plan. 1. Maintenance methods and standards. Maintenance methods: 1) According to the requirements of operation procedure to hand over, replacement of qualified, mechanic carry canister, vinyl chloride olfactory sensitivity instrument, have spirit and preventing station staff supervision, can overhaul of the valve. ( 2) Turn off the gas source, remove the locator and the air tube, to dismantle the valve ( 。 3) Connection of valve stem and valve core check valve core stem connection status, check whether the connecting pin is can remove, can't get off with a special tool to take, or hole. 2. After repair the valve assembly. ( 1) Assemble all the components for a valve cleaning before inspection, the assembly sequence should be from the bottom up, join the gasket should be coated with grease, add filler to enrich the uniform. ( 2) Tighten all bolts and packing before assembly should be covered with grease for the next maintenance and lubrication. 3. Adjustment of the valve. After the valve assembly mount locator, adjustment of air pipe. Calibration point should not be less than five points, 0%, 25%, 50%, 75%, 100%. Slowly will each point in turn signal input locator, observation schedule whether the pointer and scale label corresponding, otherwise should be adjusted repeatedly, until reach the standard. 4. Commissioning and acceptance. ( 1) Loaded on the pipeline after the valve calibration standard, confirm no problem notification process workshop, after the hand over formalities. ( 2) Cooperate with technology personnel from the hand to general control operation. ( 3) Check after repair records information is complete and accurate. ( 4) When the valve is introduced into medium to check whether the packing and on both sides of the flange is leaking. ( 5) Normal operation of pneumatic control valve after 72 hours, by the relevant technical director to sign for qualified.