Shandong heat exchanger maintenance 2. The main assembly parts of shell and tube heat exchanger are front-end tube box, shell and back end structure (including tube bundle). The detailed classification and code (English letter) are as follows: 3. The representation of heat exchanger model is the number of tube / shell processes of heat exchanger, and the write nominal length (diameter ()) of single shell process, -The nominal heat exchange area outside the heat exchange pipe () design pressure of the pipe / shell side (), only the nominal diameter (diameter in the box) is written when the pressure is equal. For the kettle reboiler, the denominator is the inner diameter of the cylinder. The first word for the tube is the maintenance mother of Shandong heat exchanger, the second letter represents the shell type type, the third letter represents the rear end structure type Ķ floating head heat exchanger and flat cover tube box, with nominal diameter of 500mm, the design pressure of pipe side and shell side are 1.6Mpa, the nominal heat exchange area is 54 ㎡, and the outer diameter of the cold drawn heat exchanger is 25mm, The floating head heat exchanger with a length of 6m and a single shell side of 4 pipe passes is made of aes500-1.6-54-6/25-4 Ⅰ Ķ fixed tube plate heat exchanger and head pipe box, with a nominal diameter of 700mm, a design pressure of 2.5MPa, a design pressure of 1.6Mpa on the shell side, 200 m2 of maintenance product of Shandong heat exchanger on the nominal heat exchange surface, 25mm in outer diameter and 9m in length, The fixed plate heat exchanger with 4-tube side single shell side is bem700-2.5/1.6-200-9/25-4 I ￣ U-type tube heat exchanger. The head pipe box has a nominal diameter of 500mm, the design pressure of the pipe side is 4.0Mpa, the design pressure of shell side is 1.6Mpa, the nominal heat exchange area is 75 ㎡, which is 19mm higher than the outer diameter of * * cold drawn heat exchanger, 6m in length and U-tube heat exchanger in the single shell side of 2-tube, The model is: biu500-4.0/1.6-75-6/19-2 Ⅱ Ⅱ ￣ kettle reboiler, flat cover tube box, diameter of pipe box is 600mm, diameter of cylinder is 1200m, design pressure of pipe side is 2.5MPa, design pressure of shell side is 1.0MPa, nominal heat exchange area is 90m2, outer diameter of ordinary cold drawn heat exchanger is 25mm, pipe length is 6m, and 2-way kettle reboiler, The model is akt-600/1200-2.5/1.0-90-6/25-2 Ⅱ ట floating head condenser and head pipe box, with nominal diameter of 1200m, design pressure of pipe side of 2.5MPa, design pressure of shell side of 1.0MPa, nominal heat exchange area of 610 m2, outer diameter of ordinary cold drawn heat exchanger pipe of 25mm, pipe length of 9m and single shell side of 4 pipe, The model is bjs1 200-2.5/1.0-61 0-9/25-4 Ⅱ (I) heat exchange pipe and arrangement on the tube plate. The heat exchange pipe is the heat transfer element of shell and tube heat exchanger, which is directly in contact with two media. Therefore, the shape of heat exchanger Shandong heat exchanger maintenance and size have a great influence on heat transfer. The small pipe diameter is easy to bear pressure, so the pipe with thin wall and more tubes can be arranged in the same shell diameter, which makes the heat transfer area per unit volume of heat exchanger increase and scale compact, the metal consumption per unit heat transfer area is less, and the heat transfer efficiency is slightly higher, but it is difficult to make the small diameter pipe scale and is not easy to clean. Therefore, small diameter pipes are generally used for clean fluid, and large diameter pipes are used for viscous or polluted fluids. The common heat exchanger tubes of shell and tube heat exchanger in China are: carbon steel and low alloy steel pipes have Φ 1 9 × 2、 Φ twenty-five × 2.5、 Φ thirty-eight × 3、 Φ twenty-five × 2、 Φ thirty-eight × 2.5。 Φ fifty-seven × 3.5; Stainless steel pipe has the same heat transfer area, the longer the heat exchange pipe, the smaller the diameter and wall thickness of the shell and head, the better the economy; But the heat exchange pipe is too long, the economic effect is no longer obvious and it is not convenient to clean, transport and install. The maintenance length of Shandong heat exchanger of heat exchanger of heat exchanger is 1.5, 2.0, 3.0, 4.5, 6.0, 7.5, 9.0 and 12.0m. In the heat exchanger used in the refinery, the commonly used length is 6m pipe length. In order to strengthen heat transfer, screw tube, screw tube and fin tube can be used for heat exchange pipe. The arrangement of heat exchanger tubes on the tube plate includes positive triangle, corner triangle, square and corner square. As shown in the figure. Triangle row pipe is many, structure is compact, but outside cleaning is not convenient; The square row pipe is less, the structure is not compact, but the cleaning outside the pipe is more convenient. Generally, triangle arrangement is used in fixed tube plate heat exchanger, and floating head heat exchanger is square arrangement for Shandong heat exchanger maintenance. 