1 piston improvement 1.1 Defect analysis of traditional piston The conventional piston uses a steel plate welded structure to reduce the weight of the piston and achieve the balance with the secondary inertial force. The piston and the piston rod are connected by a concave nut. Due to the limitation of the operating space, although the special tool is used, the nut is not easy to be tightened in place, and sometimes even if it is screwed into place, the locking device is unreliable, and after running for a period of time, The piston nut will loosen, causing a great noise, and in serious cases, the piston may hit the cylinder. In addition, due to the looseness of the nut, the piston is rotated, the positioning pin of the piston rod is easily cut off, and the position of the wear-resistant alloy layer on the piston is rotated, causing the bearing surface to decrease and the wear of the wear-resistant alloy layer to be intensified. 1.2 improved method of piston (1) The 2D12-100/8-I air compressor changes the concave piston nut to the exposed lock nut and the retaining washer structure to prevent the nut from loosening. (2) The steel welding piston is made into a split-type cast aluminum piston, which not only reduces the weight of the piston, but also achieves the balance of inertial force, and at the same time overcomes the problem of cracking of the welding piston. (3) Add a steel lining ring at the shoulder to reduce the specific pressure of the cast aluminum piston and the piston rod connecting shoulder. From the practical point of view, the cast aluminum piston used in the 2D12-100/8-I air compressor has no previous piston failure in use, and it runs well, which greatly improves the reliability of the compressor operation. 2 fuselage base design and improvement of foundation construction The 2D12-100/8 air compressor fuselage base and the foundation are connected by a fixed connection. This connection has obvious defects. See also the improved 2D12-100/8-I air compressor adopts double support plate structure. Overcome the shortcomings of fixed connections. The reciprocating linear motion generated by the connecting rod under the driving of the crankshaft causes, for various reasons, that the secondary connecting rod cannot generate a symmetrically balanced two force, which causes the fuselage to produce a reciprocating linear motion tendency, and the connecting body and the body The bolts on the foundation will be affected by the alternating load, and the stress concentration phenomenon will occur in the threaded parts. It is easy to cause bolt breakage under continuous bending and squeezing. Our company's new No. I air compressor station 3# and 5# air compressors have experienced the phenomenon of anchor bolt fracture, which brings great hidden danger to the safe operation of the compressor. The double support plate structure is adopted, and the support plate is fixed on the foundation by the anchor bolts, and the fuselage slide bolt is fastened in the T-shaped groove of the support plate, thereby ensuring that the fuselage is in the cylinder direction under the unbalanced alternating load. There is a certain amount of activity on the side, which reduces the impact on the anchor bolts. Improvement of the seal between the crankcase end cover and the crankshaft The shaft end of the 2D12-100/8 air compressor crankshaft is sealed with two-way felt. The felt is pressed into the trapezoidal groove of the end cap. The structure is simple, easy to maintain and replace, but only for places where the line speed is less than 5 m/s. From the motor speed n=500r/min, the shaft diameter D=195mm, it can be seen that the line speed v=Dn/60000=3.14×195×500/60000=5.1m/s, which is close to the speed critical, so the oil leakage at the shaft end is inevitable. The problem cannot be solved completely. The 2D12-100/8-I compressor uses an outer felt inner lip seal to seal. The lip seal differs from other seals in that it is made of oil-resistant rubber or leather and has a resiliently elastic lip that is pressed against the lip of the seal by an annular coil spring for added sealing. Due to the special shape of the lip and the action of the upper clamping spring, the lip-to-shaft has good follow-up compensation performance. Practice has proved that the sealing effect of the oil seal structure is good, and no serious oil leakage is found after the 2D12-100/ 8-I air compressor is put into operation. Due to the split type of the 2D12-100/8 air compressor shaft side cover and the improved integral structure, the modification of 7 2D12-100/8 air compressors of the new I air compressor station It is recommended to replace the inner road felt with a U-shaped non-skeleton rubber oil seal. The seal has the following characteristics: (1) the section is U-shaped, only spring and no skeleton, can be used in trapezoidal grooves; (2) suitable for splitting machine base; (3) suitable for temperature at -25 °C ~80 ° C, line speed <7m / s condition. 4 Unit cooling system pipe network structure improvement According to the thermodynamics knowledge, the compression process of the compressor is closer to isothermal compression, and the less compression work is consumed. Therefore, the heat transfer performance of the air cooler is improved, the heat transfer effect is ensured as much as possible, and the secondary compression process is as close as possible to isothermal compression. This is of great significance for saving energy and ensuring the safe operation of equipment. In theory, the cooling is not perfect for every 3 °C increase, the power consumption is increased by 1%. 2D12-100/8 type air compressor, the cooling system adopts the structure of serial and parallel mixing, and its cooling water is 3 ways: (1) cooling Water inlet pipe → intercooler → total drain pipe (2) cooling water inlet pipe → aftercooler → total drain pipe (3) cooling water inlet pipe → first stage cylinder water jacket → oil cooler → secondary cylinder →The total drain is insufficient for the cooling line in the third way. Since the cooling water after the exchange of the primary cylinder has a large temperature rise, the effect of cooling the lubricating oil and the secondary cylinder is certainly not satisfactory. Our company's new I air compressor station 1# ~ 7# air compressor before the transformation in the summer when the problem is very prominent, the oil temperature is up to 50 ° C or more, the secondary exhaust temperature is above 160 ° C, multiple alarms, automatic Parking phenomenon. The 2D12-100/8-I air compressor adopts the parallel cooling form instead of the original design of the serial and hybrid cooling structure. The cooling route is divided into 5 roads, and the water from the main inlet pipe passes through the respective cooling points, and is collected in the drainage main pipe to be recycled by the cooling water tower. Although the amount of cooling water per unit has increased, due to the use of a circulating water supply system, the water supply capacity can meet the requirements, so there is no waste of water resources. Practice has proved that this kind of cooling form has better effect, the oil temperature can be controlled below 40 °C, and the secondary exhaust temperature can be controlled at about 120 °C, especially for the operation of the secondary cylinder parts. The modification of the 1 #～7 # air compressor cooling system of our company's new I air compressor station has achieved the same effect. 5 Conclusion 2D12-100/8 air compressor and its improved type as a large-scale power equipment, occupy a dominant position in our company's compressed air supply. Its safe operation directly affects the supply of compressed air of our company and affects the steel rolling system. Normal production, so it is particularly important to improve the problems in design and installation, reduce the failure rate and improve the operational reliability. Rotary Valve,Hawe Rotary Valves,Special Vehicle Valve,Directly Rotary Valve Jiangsu KM Hydraulic Control System Co. Ltd. , https://www.km-valves.com
The 8 #Air Compressor and the New II Air Compressor 5 air compressors put into operation in 1997 by Angang New I Air Compressor Station are 2D12-100/8-I products, and the new I air compressor station Compared with the other 7D2-100/8 air compressors, the compressor piston, the fuselage base, the crankshaft shaft end seal and the cooling circulation system have been greatly improved in design and installation. The operation of the 8# air compressor of the station for nearly 3 years and the operation of 5 air compressors of the new II air compressor station for more than half a year, the 2D12-100/8-I air compressor is more reasonable in design and faulty. The rate is obviously reduced, and the maintenance is convenient.