Reverse Flanges

All but two of the bolts Joining the relief valve to the flare header are removed. The sealing plate is then inserted between the relief valve and the flare header. It is secured by special bolts with small heads that pass through the bolt holes in the relief-valve flange but not through the holes in the sealing plate. The last two bolts can then be removed and the relief valve removed. To replace the relief valve the procedure is reversed [2]. 

Figure 9.1 Schematic diagram of the MBR65.1, Reaction vessel 2, top flange 3, cold-finger 4, pressure meter 5, magnetron 6, forward/reverse power meters 7, magnetron power supply 8, magnetic stirrer 9, computer 10, optic fibre thermometer 11, load matching device 12, waveguide 13, multi-modal cavity (applicator).

Reestablish the main burner fuel supply (either by cormecting the main fuel line, removing a blind flange, or reversing fhe double block and bleed valve assembly) to provide a fuel source to the furnace. 

Tr, Ur, Yr = K-factors for reverse flanges t = flange thickness, in. t =pipe wall thickness, in. 

Figure 2 14. Dimensional data and forces for a reverse flange.

First, this compressive force could be transferred through direct contact with any connections, but this is not done because of concern about the structural integrity of the entire building (see the elementary function EFj and EEg), not to mention that the bending moment s sign could be reversed. For all these reasons, top and bottom flanges in a fixed beam are usually connected in the same way with the column. 

Reversal on Pinch Point. Often, a reverse bend is put in the piece so that on the subsequent bends, the action of the metal bending up will interfere with the backgauge finger. (See Fig. 17.) This feature allows the back-gauge to retract away from the die to clear flange AB as it flips up. 

The process temperature is measured in the uncondensed gas as it leaves the chlorine knockout pot or separator. This procedure is more accurate than measurement of the temperature of the liquefied chlorine, which may be subcooled. The tenqierature sensor in Fig. 11.29 is an RTD in a flanged Monel thermowell. The reverse-acting proportional-plus-integral controller adjusts the set point of the refrigeration chiller pressure controller. 

Reversing the sprocket on the shaft can sometimes extend the life of a worn sprocket. But this is only possible if the flange is centered on the hub, or if there is space to do so. 

The most relevant feature of the MARS plant affecting decommissioning concerns the easy disassembling of components, thanks to the adoption of flanged connections in the primary loop. Each component (even SG and pressure vessel) may be disassembled for maintenance or substitution in an operation basically the reverse of the assembly. Normal precautions regarding dose limits to personnel are the main differences. 

Further development of design mles in the ASME Code, VIII-1, came with the issuance of reverse flange rules that use a ring-type gasket with no additional contact of the faces. These mles were added to Appendix 2, ASME Code, Vin-1. 

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