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Expanding rod (head) instructions

Expanding rod (head) instructions

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First, use

1. Before the expansion, the sharp mouth or burr of the end of the heat exchange tube must be removed to avoid damage to the liquid bag.

2. Before installing or replacing the expansion rod, use a syringe or other method to fill the expansion rod with water or the selected expansion medium to remove the air inside the expansion rod.

First, use

1. Before the expansion, the sharp mouth or burr of the end of the heat exchange tube must be removed to avoid damage to the liquid bag.

2. Before installing or replacing the expansion rod, use a syringe or other method to fill the expansion rod with water or the selected expansion medium to remove the air inside the expansion rod.

3. Whenever the expansion rod and hose are replaced, the air in the ultra-high pressure system must be emptied and the expansion medium should be replenished in time to avoid affecting work efficiency and ensuring safety.

4. Before the formal expansion, the no-load start, so that the hydraulic circuit of each hydraulic system is fully circulated for 5-10min.

5. When the expansion joint is connected, the extension line of the heat exchanger expansion joint (opposite the heat exchanger) shall not stand, otherwise the steel plate or other methods shall be used for protection.

6. For the nozzle that can not be inserted into the partial expansion rod, the defects such as the tube burr and the welding tube can be treated first. After the treatment is invalid, the expansion rod can be fully ground and then inserted into the cylindrical grinding machine, but the inner diameter of the tube and the expansion rod The gap between the outer diameters does not exceed 0.3 mm, and the outer diameter of the expansion rod will affect its service life.

7. When inserting or pulling out the expansion rod, it is strictly forbidden to twist the expansion rod.

8. It is forbidden to expand the joint before the expansion rod is inserted into the tube hole or not fully inserted into the tube hole, so as not to damage the expansion rod.

9. During the operation of the expansion tube, the expansion head must be pulled out after the pressure is completely relieved. If the expansion rod is not fully removed before the pressure is removed, the expansion rod will be seriously damaged.

Second, the life span

1. The life of the expansion rod is realized by controlling the total gap (the gap between the inner diameter of the tube sheet hole and the outer diameter of the heat exchange tube and the gap between the inner diameter of the heat exchange tube and the outer diameter of the expansion rod) between 0.6 and 0.8 mm. Therefore, the total gap <0.6mm, the life will be longer; the total gap>0.8mm, the life will be reduced; the total gap>1mm, the life will be lower.

2, the life of the expansion rod is an average, the same size, the greater the number, the longer the average life, the shorter the opposite, the less than 10 can not ensure the life; the different diameters, the longer the average life, On the contrary, the shorter the length; the longer the expansion rod, the shorter the average life, and vice versa.

3. Under normal circumstances, for the expansion rod of 19× 2× 50, the expansion pressure is below 150Mpa, which can ensure 150 times expansion/support. The expansion pressure is 150-200Mpa to ensure 100 times expansion/support. The pressure is 200-250 Mpa to ensure that the expansion is 50 times / support.

Third, the adjustment pressure indicates the reference value of the hydraulic expansion joint pressure of the conventional tube sheet and the heat exchange tube:

2. The strength expansion needs to meet the slotting requirements: the groove width is 8-10mm. Due to different materials, batches, groove widths, etc., the expansion pressure can be adjusted according to the degree of inspection after the expansion test & ldquo;

3. If the material and specifications of the tube sheet and the heat exchange tube are different from the above, or there are special expansion requirements, it is recommended to first perform the expansion joint test, whichever is the result of the test.

Yangfa Machinery is committed to research and development of various types of tube expanders, such as: high pressure tube expander, rubber tube expander, fin tube expander, etc., and various hydraulic expansion rods, hydraulic expansion rod machines, to undertake expansion tube outsourcing engineering services ! 24-hour consultation telephone: 13585210218