Support Rings

On reassembly, care should be taken to return the tilting-pad and support-ball combination to the original location in the support ring. Changes in clearance and concentricity can result if the tilting-pad and support-ball combination is not returned to the same location. An eccentricity of as little as one mil can cause severe vibration problems. 

Leaving tray support rings in towers revamped with packed beds. Poor separation. Premature flooding. Installation error. There are too many examples of this for us to continue to make this one. If you are not confident enough to remove the tray support rings, don t pack the tower. 

Solution The distributor was securely and evenly clamped to its support ring. 

Unterlauge, /. (-Soap) underlye, spent lye. unterlegen, v.t. lay under, put under, underlay. Unterleg-ring, m. supporting ring, -scheibe, /. 

When placing mesh in small diameter vessels it is important to discount the area taken up by the support ring before determining the operating velocity of the unit. For small 6-, 8-, and 12-inch vessels (such as in-line, pipe-with-mesh units) it is usual practice to use 6- or 8-inch thickness of mesh for peak performance. 

Deduct 4 inches from effective diameter for 2-inch support ring inside. 

The number of irrigation or drip-points or entrance points per square foot of flat surface of the tower should be uniform for orifice, weir-type gravity, or pressure distributors, and need not exceed 10 points/ft [82]. This imiformity must not be disturbed by support rings for supporting the distributor itself. The distribution must include the area adjacent to the wall, and the design must not force more liquid at the wall where it contacts the packing. Uniformity of points of distribution to the packing surface is extremely important. The volume flow per point must be carefully calculated. 

Figure 9-8H. Orifice pan liquid distributor with round or rectangular chimneys and a flat floor sealed to vessel support ring. For a large vessel, it can be sectioned to pass through a manway. Used by permission of Jaeger Products, Inc., Bull.-1100.

The area available for perforation will be reduced by the obstruction caused by structural members (the support rings and beams), and by the use of calming zones. 

The width of the support ring for sectional plates will normally be 50 to 75 mm the support ring should not extend into the downcomer area. A strip of unperforated plate will be left round the edge of cartridge-type trays to stiffen the plate. 

In vacuum distillation columns, the plate-support rings will act as stiffening rings and strengthen the vessel see Example 13.2. 

A vacuum distillation column is to operate under a top pressure of 50 mmHg. The plates are supported on rings 75 mm wide, 10 mm deep. The column diameter is 1 m and the plate spacing 0.5 m. Check if the support rings will act as effective stiffening rings. The material of construction is carbon steel and the maximum operating temperature 50° C. If the vessel thickness is 10 mm, check if this is sufficient. 

NB2001 (23), a prodrug of triclosan, has been developed based on the enzyme-catalyzed therapeutic activation (ECTA) concept. Evidence supporting ring opening of the cephalosporin moiety by penicillin-binding proteins and/ or (3-lactamases to release triclosan at the bacterium site, as well as sub-pg/mL MIC on [3-lactamase-positive strains, demonstrates the potential of this approach [42]. 

Army Type 94 Floating Smoke Candle consisted of a cylindrical metal tube 3 VA inches long and 3% inches diam, equipped with a supporting ring to which an automobile rubber tube was attached. 

Finally, during routine internal inspection of the Murchison unks after 3 months of operation to check for signs of erosion or other damage, it was found that mechanical failure had occurred on all Five unks. Failure had occurred on approximately 25% of the liner-to-liner-head welds and at a stress point between the central coupling and support ring on all five units... 

Shaft 2, Seal element 3, Cooling 4, Three-piece segmented ring 5, Six-piece semented ring 6, Support ring. 

The common reason for out-of-levelness of trays is sagging of the tray decks. Sags are caused by pressure surges and sloppy installation. Sometimes, the tray support rings might not be installed level or the tower itself might be out-of-plumb (meaning the tower itself may not be truly vertical). 

Add 2 in. for support rings, making the diameter 30 in. Tray efficiency from Eq. (14.38) ... 

With 2 in. support rings the pad will have a diameter of 34 in. The size of the drum is set largely by the required liquid holdup of 250 cuft. On the basis of Figure 18.7, the height of vessel above the liquid level is 4 ft. As in Example 18.2, take the diameter to be 4.5 ft. Then... 

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