Retaining devices

Secondary Cause—There was no secondary retaining device in the event of thread failure. Contributory Factor— The operator closed a valve deadheading and pressuring the system with compressed air. 

The Engineering Department should investigate the practicality of installing secondary retaining devices. 

A typical wire retainer device for holding the bags vertically and preventing them from collapsing under high air pressure is shown in Figure 20.3(c). 

CA thermocouple 2. Liquid sample, 4, Dewar flask 4. Retaining device 5. Spring 6, Glass cup 7. Glass lid 8. PTFE (polytetrafluoioethylene) lid 9, PTFE sealing 10. PTFE capillary tube 11. Stainless steel strip. 

Hold-Down Plates and Bed Limiters (Retaining Devices)... 

Random packing fluidization during even relatively minor upsets (such as column flooding) is common when a retaining device is absent. In large-diameter columns, packings tend to fluidize at random spots rather than imiformly over the entire top surface. Fluidization... 

Figure 8.7 Retaining devices, (a, b) Hold-down plates (c, d) bed limiters. (Parts a to c rquinted courtesy of Koch Engineering Company, Inc. part d reprinted courtesy of Norton Company.)...

The retaining device must have at least the same capacity as the packed bed. It has been recommended (111, 305) that retaining devices provide an open area of at least 70 percent of the column cross-sectional area. 

Hooks need a retainer device that prevents rigging from slipping out of the jaw. There are some patented designs that accomplish this. The retainer allows rigging to slip into the jaw easily, but prevents it from slipping off the jaw. The retainer devices will not carry a load. They merely keep rigging in the jaw. 

Thermionic channel "Yenise/ 1, Emitter 2, Collector 3, Metal-ceramic units 4, Bellows units 5, Spacers 6, External insulation 7, Cesium input 8, Fuel 9, End reflector 10, Retaining device 11, Current leadouts... 

Figure 5.13 A fire door retaining device - an example of the application of technical progress...

The Deutsche Institut fiir Bautechnik (DIBt) publishes a media list for glass fiber reinforced plastic laminates made from UP/PHA resins [7] that provides proven minimum properties according to DIBt requirements for issuing certifications for containers, retaining devices and pipes. Appendix Tables A.49 to A.54. 

Without a retaining device, the bed will start to expand if flow in the upwards direction is sufficiently high. Even if a bed retaining device is fitted the particles will still tend to move and rub against each other and cause attrition to occur. In order to avoid this problem it is normal practice to limit the allowable upwards velocity for packed beds to less than about 80% of the minimum fluidization velocity calculated from equation (6.70). 

Disc/BallA/ane detachment or stem/attachment part fracture. -Render any valve type inoperable, and one of the Consequences for sticking open, closed or midposition would occur -Structural failure of retaining devices/parts -Fatigue - Overtorquing/Loading -Corrosion... 

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