Valve packing

Because of its chemical inertness over a wide temperature range it is used in a variety of seals, gaskets, packings, valve and pump parts and in laboratory equipment. 

The apparatus was constructed entirely of stainless steel. The pump packing, valve packing, O-rings and solenoid valve seats were all made of Teflon. 

Injection-molded parts such as electrical connectors and sockets, distillation column plates and packings, valve bodies pipe and fitting linings are easily made because ETFE exhibits a low shear sensitivity and wide processing window 42... 

Sample Inlet System. A detailed diagram of the inlet system is shown in Figure 2. All pipework on the system is 1/4-inch stainless steel tubing except where otherwise designated. Valves 1-10 are Vg-inch stainless steel Hoke valves with V-stems and Teflon packing. Valves 2, 4, 6, and... 

Flanged connections in sizes 24in. to 6ft Flanged connections in sizes above 6ft Packed valves up to in. stem diameter Packed valves above in. stem diameter Lubricated plug valves Petcocks Sight glasses... 

For transparent columns that do not have packing valves, it is easiest to let the resin settled overnight in the column. For all others, calculate the amount of settled resin using the total volume and percent slurry from the 1 liter graduated cylinder. If necessary, remove or add resin to achieve the desired packed bed height. Do not rely on the calibration marks on large containers as they are generally inaccurate. 

Introduce the resin into the column by the bottom packing valves with the requested flow rate (top process valve open) controlling the pressure (Figure 4.29a) After the column is filled with slurry (Figure 4.29b), slurry is continued to be introduced into the column, with the bed starting to build up from the top (Figure 4.29c). 

Inject buffer upflow through the packing valves in order to flush them. Buffer is sent back to the buffer tank. 

Bed height adjustment close the packing valves but keep the process top valve open. Then move down the piston until the final bed height is reached. 

Check periodically for leaks from sources such as pump packings, valves, gasketed covers, sight glasses, pipe joints, and so forth. 

A leak at a valve stem on an ammonia cylinder in service with a packed valve can usually be stopped by tightening the packing nut, which has a left-hand thread, in a counterclockwise direction. If this fails, the valve should be... 

Cylinder valve stem leaks on packed valves can often be stopped by tightening the packing nut in a clockwise direction. If the leaks persist, the gas supplier should be contacted for further instructions. 

Diaphragm valve A packless valve that utilizes clamped, flexible disk(s) to seal the opening through which the internal parts are installed. (Also see packed valve.)... 

Packed valve A valve that utilizes compressed packings to seal the openings through which the valve internal parts are installed, e.g. an O-ring valve. (See diaphragm valve)... 

Packed valves similarto the cylinder valve previously described, may also be used. They have an advantage over diaphragm valves when regulating flow since regulating stem tips (seats) may be used with very fine threads on the stem to allow for precise flow control. The packed design... 

Provision should be made to collect coolant vented and drained from the RCSASs. Leaks can occur from, among others, double packed valve stems, valve seats, pump seals and intergasket cavities during reactor operation. 

A.27. The heavy water collection system should be designed to cohect leaks from any anticipated leak source in the RCS, such as double packed valve stems, pump seals and intergasket cavities. The system should also be used to cohect venting and draining fluids from the RCSASs and from equipment of other systems. 

---