In valve design or the use of experience, many jack-fill valve for asbestos packing or graphite filler or PTFE V-packing, but these types of fill valves are subject to restrictions on the number of headstock That with the increase in the number of gate valves, fill will be wear and tear, gap increased gradually, to a certain number (According to the statistics will not be more than 2000 times) valve Department will have a leak from the filler.
After the required disclosure of the new compact packing gland. This program suitable for a low frequency valve sluicegate occasions.
If the gate valve frequency, (such as headstock 10-30 million a year), which will increase the use of valves, maintenance costs.
Is there a gate valve can in the 100-200 million times, still be able to seal the design of it? The answer is yes.
One way for an increase in the fill below a washer in the bottom plus a spring washer (spring preload required for calculation), when the packing wear, because the role of spring, it will Re-compacting filler to seal. This approach is currently through the use of testing, can only achieve the headstock 50-100 million non-disclosure, required the use of side in the annual overhaul, to re-compacting fill Gland, can only reduce the maintenance of peace.
Another way is to choose hydraulic, pneumatic sealing technology and change the original valve design ideas, in the sealed fuel tank filler Department slipring to increase the 0-type seal (necessary calculation
Friction, sealing pressure, in order to determine the slip-ring and 0-type seal of the quantity). Using this approach, be able to achieve the headstock 2,000,000 times not to divulge, but the 0-type seal to aging The use of only 5 years, while costs are relatively high.
