Support pipe racks

Multielevation piperacks are usually needed to handle all the required services for piping, electrical, utilities, and instmmentation. The two-level rack is one of the most common but three-level ones are also used. The utility lines are usually mn in the upper level and the process lines in the lower levels. The larger-diameter lines are located to the outside of the rack to be closest to the column supports. Access platforms are required at the battery limit to provide operators access to the block valves and blinds. If long mns of hot pipe are required, a portion of the pipe rack needs to be dedicated to an expansion loop. A horizontal space in the piperack is provided for a set of lines to be flat-turned into a set of expansion loops with the large pipes located on the outside. AH of the pipe turns are in the same horizontal plane, which is an exception to normal piping practice. A flat turn takes up and blocks space for other pipes. Flat turns are generally only made from the outside of the rack to minimize this blockage. 

Minimum size of pipe is, sometimes dictated by structural considerations, i.e., l/i-inch Schedule 40 steel pipe is considered the smallest size to span a 15 to 20 pipe rack without intermediate support. 

Main pipe rack structures in process units that also support equipment 2-3 hours... 

Main process area pipe racks and interconnecting pipe racks (located in process areas and supporting piping only) should be fireproofed from their bases up to and including the first-level pipe support beams for a 1- to 2-hour rating (see Figure 8-6). 

Main pipe racks located in process or other fire potential areas that also support equipment such as fin-tube air coolers should be fireproofed with a 2- to 3-hour rating from their bases up to and including the equipment support legs and any horizontal beams transmitting the... 

Main banks of aboveground instrument runs in cable trays (such as those coming from the control room and supported on process unit pipe racks) that are located inside process unit battery limits should be considered for fireproofing by one of the following passive methods ... 

Overhead pipe support structures or pipe racks... 

Pipe racks and load-bearing piping supports located in areas with a high fire exposure can be protected by one or more of the following passive or active features ... 

The cooling of steel supports of any container or pipe rack that may be subjected to high heat levels. This is most effectively accomplished by the application of narrow spray streams to the highest part of die support being heated and permitting the water to run down the vertical length of the support. 

Pipe racks - bents, supports, hangers, sleepers, t-supports. 

Piping and supports design calculations Stress analysis report for piping Piping layout and isometric drawings Pipe rack drawings Miscellaneous piping accessories Hydrostatic test and other tests report Tie-in list... 

The bottom support elevation of the main pipe rad< is dictated by the maintenance and piping clearance beneath the pipe rack, with additional levels spaced at 6-ft (1,800-mm) intervals. On projects with very large diameter piping, increasing this dimension to suit clearance requirements should be considered when pipe direaion is changed. External clearances (e.g, over main roads or intersections with off-.site pipe racks) need close attention. Exhibit 3-20 shows a typical pipe rack elevation. 

Pipe racks within vertically structured or housed facilities cannot be defined as easily as for inline arrangements, because the equipment is usually located on several levels. The venical units are usually fed by conventional pipe racks at established elevations entering the structure at a designated area. Once inside the structure, piping should be routed in an orderly manner according to economic, constructibility, and support requirements. Exhibit 3-22 displays a typical process structure. 

Air coolers, shown in Exhibit 3-27, are generally supported from the central pipe rack adjacent to their... 

Air coolers are located adjacent to the equipment that they serve for piping flexibility and maintenance. They can be supported from grade, at the top level d structures, or above pipe racks, w4nch is the most common installation. tube bundle bank can be... 

Snuffing steam, which is used to suppress a fire in the header box in the convection or radiant sections, is supplied through local and remote manifolds. The remote manifold shoulintermediate pipe support column. If the local area is unreadi-able in an emergency, steam would be supplied from the remote manifold. The inlet and outlet control stations are located along the pipe rack adjacent to die furnace. This particular fiimat uses manually controlled valves for each burner. The burner supply headers—fuel gas, fire steam, and fuel oil—are run... 

When locating lines in the rack, the plant layout designer should run the largest lines near the outside where possible to reduce the overall load on the supporting beams. Meter runs should be installed direaly next to die columns so diat access is available by portable ladder or mobile platform, as shown in Exhibit 11-11. Maer runs are located in the pipe rack only when absolutely necessary. 

Exhibit 11-22 shows how larger lines in a pipe rack are used to support a group of smaller lines that may not be adequately supported because of the bent spacing. The uninsulated line is U-bolted to the supporting steel the insulated line has its shoe welded to the steel The smaller lines then rest on the steel. When an insulated line is used for support, the growth of the line at the proposed support point must be checked. Its growth could become restriaed by this type of... 

Such equipment as drums and deaerators is often located above pipe rack columns. To avoid wasting valuable rack space with the large support columns, the inside face of the pipe rack column must line up with the inside face of the equipment support column, as shown in Exhibit 11-26. This approach also allows the feed-water outlet piping to run venically down to the pump before the expansion loq> is added. 

Fireproofing of pipe rack columns is shown in Exhibit 11-27. If hydrocarbons are prevalent, it is common to fireproof the columns to a level just below the lower rack supp>ort beam. If air coolers or other equipment is located above a pipe rack, the fireproofing is extended to the equipment support beam. This issue must be reviewed with the client allowances may need to be made for as much as 4 in (100 mm) of fireproofing. 

The cooling of steel supports of any container or pipe rack that may be subjected to high heat levels. This is... 

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