In order to solve the problem of leakage and short service life, we analyzed and studied the process conditions and equipment structure. It is considered that the structure of floating seal ring plus pressure relief ring and the packing structure of asbestos packing are not applicable in the conversion system because (1) the circulating water is in direct contact with the gas in the system, the solubility of H2S and CO2 in the gas under high temperature and pressure Increase, acidic substances on the corrosion of equipment increased. (2) Floating seal ring structure is sealed by the role of discharge. Equipment at work, high temperature and high pressure liquid through the floating sleeve and the floating ring, the throttle gap between the sleeve gradually pressure after the accumulation of the discharge port, the discharge port to the pump inlet. High-speed high-temperature liquid has a large scouring force, resulting in floating sleeve, floating ring, sleeve erosion erosion wear and tear. (3) Asbestos packing hard, high-speed high temperature, exacerbated the sleeve wear.
We retrofitted the R-type circulating pump to pump 100R-37 as an example:
1, Figure 1 is a modified 100R-37 hot water circulation pump seal structure. The sealing structure is composed of a sealing body (original structure unchanged), a bushing (cast iron), an end cover (cast iron), a bushing (cast iron), a gland (0Cr18Ni9, as shown in FIG. 2) ), Expanded graphite ring (φ65 × φ45 × 10), spacer ring (cast iron, φ65 × φ45 × 5). This structure works well.
This seal body structure has the following advantages:
1, the structure is simple, easy to transform. The original sealed body unchanged, only processing a φ75 × φ65 × 105 cast iron sleeve can be pressed into. Expanded graphite ring can be sentinel processing, the ring in the lathe processing can be completed.
2, installation, maintenance convenient. As shown in Figure 1, the 100R-37 hot water circulating pump shares 10 φ65 × φ45 × 10 expanded graphite rings and 6 φ65 × φ45 × 5 diaphragms. Both ends of the pump can be installed and disassembled. Graphite seal ring and interval ring installation, mouth end three do not ring. Under normal circumstances, a group of packing operation for one year, depending on the circumstances of the mouth three months, generally about four months to replace (due to pressure, temperature instability caused). When assembled as a whole, the expanded graphite seal ring is not cut. The second replacement of the mouth end of three, we should clean the mouth end of the internal, ready to replace the three cut into one or symmetrically cut two 45 ° incision, three gaps staggered installation.
3, the sealing effect is good, no leakage.
4, long service life. The whole set of packing is changed once a year Mouth three generally six months to replace. Seal body can be used for three years, packing sets from the original three months increased to about two years.
5, good economic returns The original floating ring structure, 100R-37 hot water circulation pump to be three groups of floating ring and a pressure relief ring, a set of value 700 yuan, switch to expanded graphite ring, only 60 yuan per year. After modification, there is no recurrence of parking. Due to the removal of the pressure relief ring, pressure relief hole is blocked, can save 1 to 2 tons of hot water per hour.
Matters needing attention in use:
1, Expansion of graphite larger coefficient of thermal expansion, the new filler must be empty load test. Do not preload too tight before the test. Each preload, not only to force evenly, but also need parking preload. The last preload, must be carried out at the operating temperature, otherwise it will be due to high temperature expansion shaft lock.
2, the operating pressure, the temperature must be stable. Pressure instability, affecting the use of filler. Sudden increase in temperature, graphite packing temperature rise of the shaft lock, the axial expansion of the packing gland collapse, high pressure steam out and accidents.
3, found that the mouth will be leaked three filler replacement, otherwise, the internal packing will be washed away due to leakage, the sleeve will be high-speed rotation of the swirling erosion bad.
4,80R-60 HTF circulation pump with 100R-37 hot water circulating pump.
We retrofitted the R-type circulating pump to pump 100R-37 as an example:
1, Figure 1 is a modified 100R-37 hot water circulation pump seal structure. The sealing structure is composed of a sealing body (original structure unchanged), a bushing (cast iron), an end cover (cast iron), a bushing (cast iron), a gland (0Cr18Ni9, as shown in FIG. 2) ), Expanded graphite ring (φ65 × φ45 × 10), spacer ring (cast iron, φ65 × φ45 × 5). This structure works well.
This seal body structure has the following advantages:
1, the structure is simple, easy to transform. The original sealed body unchanged, only processing a φ75 × φ65 × 105 cast iron sleeve can be pressed into. Expanded graphite ring can be sentinel processing, the ring in the lathe processing can be completed.
2, installation, maintenance convenient. As shown in Figure 1, the 100R-37 hot water circulating pump shares 10 φ65 × φ45 × 10 expanded graphite rings and 6 φ65 × φ45 × 5 diaphragms. Both ends of the pump can be installed and disassembled. Graphite seal ring and interval ring installation, mouth end three do not ring. Under normal circumstances, a group of packing operation for one year, depending on the circumstances of the mouth three months, generally about four months to replace (due to pressure, temperature instability caused). When assembled as a whole, the expanded graphite seal ring is not cut. The second replacement of the mouth end of three, we should clean the mouth end of the internal, ready to replace the three cut into one or symmetrically cut two 45 ° incision, three gaps staggered installation.
3, the sealing effect is good, no leakage.
4, long service life. The whole set of packing is changed once a year Mouth three generally six months to replace. Seal body can be used for three years, packing sets from the original three months increased to about two years.
5, good economic returns The original floating ring structure, 100R-37 hot water circulation pump to be three groups of floating ring and a pressure relief ring, a set of value 700 yuan, switch to expanded graphite ring, only 60 yuan per year. After modification, there is no recurrence of parking. Due to the removal of the pressure relief ring, pressure relief hole is blocked, can save 1 to 2 tons of hot water per hour.
Matters needing attention in use:
1, Expansion of graphite larger coefficient of thermal expansion, the new filler must be empty load test. Do not preload too tight before the test. Each preload, not only to force evenly, but also need parking preload. The last preload, must be carried out at the operating temperature, otherwise it will be due to high temperature expansion shaft lock.
2, the operating pressure, the temperature must be stable. Pressure instability, affecting the use of filler. Sudden increase in temperature, graphite packing temperature rise of the shaft lock, the axial expansion of the packing gland collapse, high pressure steam out and accidents.
3, found that the mouth will be leaked three filler replacement, otherwise, the internal packing will be washed away due to leakage, the sleeve will be high-speed rotation of the swirling erosion bad.
4,80R-60 HTF circulation pump with 100R-37 hot water circulating pump.
Auto electronics
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