Quick opening

Quick Opening Devices. Breech block, tapered or interrupted thread, or pinned closures are often used when an end cover has to be removed quickly, as with some isostatic presses (126,136), or to enable the end cover to be removed easily after the vessel has been heated to high temperatures. 

Unstayed flat heads and covers can be designed by very specific rules and formulas given in this subsection. The stresses caused by pressure on these members are bending stresses, and the formulas include an allowance for additional edge moments induced when the head, cover, or blind flange is attached By bolts. Rules are provided for quick-opening closures because of the risk of incomplete attachment or opening while the vessel is pressurized. Rules for braced and stayed surfaces are also provided. 

The actuating time for a quick-closing/quick-opening operation effected by the solenoid valves is 0.6 sec, and the actuating time under normal control is 5 sec for the inlet valves and 0.6 sec for the bypass valves. These actuating times apply to the full valve stroke outside the end position damping range. 

P—Personnel Protection QO—Quick Opening SG—Sample Protection SO—Steam Out TSO—Tight Shut Off VB—Vacuum Breaker... 

Automatic Air Storting Valves ond Quick Opening Main Air Valve... 

Runaway reactions, 405 Runaway reactions, DIERS, 521-523 Rupture, disk, 401, 418, 435, 455 Burst pressure, 456 Calculations, non-explosive, 455, 459 Code pressure levels, 410 Effects of temperature, 458 Graphite, 418-420, 424 Installation, 422, 423 Liquids, 462 Low pressure, 418, 421 Manufacturing range, 434, 456 Metal, 411 Non-fire, 465 Quick opening, 414, 415 Reverse buckling, 413 Selection features, 434... 

Valve 29 in line 14 is a quick opening bypass valve which is normally closed. However, in case of an emergency shutdown, this valve can be instantly opened to shut off the supply of alcohol to the reaction zone and return the alcohol stream via line 31 to alcohol supply tank 11. Such a quick opening by-pass valve normally is not employed in the nitrating acid line, since in case of an emergency shutdown, nitrating acid is employed to sweep out the tubular reactor... 

Figure 10-13 illustrates the flow versus valve stem travel characteristic for various typical valve trim functions (Fisher Controls, 1987). The quick opening characteristic provides the maximum change in flow rate at low opening or stem travel, with a fairly linear relationship. As the valve approaches the wide open position, the change in flow with travel approaches zero. This is best suited for on-off control but is... 

To reduce the risk of container failure, the pressure vessels are equipped with several safety features. These can include an effective self-venting system where unforeseen overpressure is released by a quick open-resealing step, or the use of safety disks which rupture when their pressure limit is reached. The small vials (0.2-20 mL) of some monomode reactors are protected by the pressure limit (20 bar) of the caps used, which is significantly lower than the operating limit of the vials themselves (40-50 bar). 

Eliminating open-ended, quick-opening valves in hazardous service... 

Explosion Pulping. In this process, wood chips about % inch long are fed into a battery of digesters (called gnns), in which the chips are steamed gradually to a pressure of 1100 to 1200 psi and then, after holding at that pressure for about 5 secs, / are released by means of a quick-opening valve into a cyclone. The explosive effect... 

Open the sampling point to maximum — about 30 seconds with pulse flushing (quick open and close) — to purge any dust and residual of the disinfectant. 

Aim able Cluster. This consists of a number of incendiary bombs held in a single container. When dropped from a plane, at a high altitude, the container opens a few thousand feet above the ground and allows the bombs to scatter over an area. For this reason it is called the delay opening type, and is distinguished from the quick-opening or short-delay type, which opens and scatters the bombs almost immediately below the airplane. As the parts from the quick-opening clusters constituted a major hazard to the planes... 

Bomb clusters and adapters, quick opening fragmentation 4 D961... 

Coalescer Head.Flanged/Quick Opening/Hinged/Davit Supports Saddles/Legs. Instruments By Purchaser/Vendors Diff. Press. Gauge, Level Gauge, Press. Gauge, Relief Valve, Temp. Indicator with Thermowell. 

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