Q Q: 506615608
Any mechanical products in the use of a period of time, it is inevitable that there will be a variety of failures, from the big fault to the small fault, one is the use method, the other is the environment where the machinery is located, all may cause mechanical damage, air compressor is no exception, and the failure frequency of mine air compressor is higher than that of general air compressor, because the dust of mine air compressor is relatively high More, let's give you an analysis of common faults.
1. Common faults and their causes
Insufficient displacement: the insufficient displacement is compared with the design gas volume of the compressor. It can be considered from the following aspects:
(1) Air intake filter failure; fouling blockage, when the exhaust volume is reduced, the suction pipe is too long, the pipe diameter is too small, resulting in increased suction resistance, affecting the gas volume, to regularly clean the filter.
(2) The reduction of compressor speed reduces the displacement: improper use of air compressor, because the discharge capacity of air compressor is designed according to a certain altitude, suction temperature and humidity. When it is used on the plateau that exceeds the above standards, the suction pressure will be reduced, and the exhaust volume will be reduced.
(3) The cylinder, piston and piston ring are seriously worn and out of tolerance, which makes the relevant clearance increase, the leakage increases and the exhaust volume is affected. In case of normal wear, it is necessary to replace the vulnerable parts, such as piston ring, etc.
(4) The stuffing box is not tight, resulting in air leakage, which reduces the gas volume. The first reason is that the stuffing box itself does not meet the requirements when it is manufactured; second, it may be due to the poor alignment between the piston rod and the stuffing box center, resulting in wear and tear, resulting in air leakage; generally, the stuffing box is filled with lubricating oil, which plays the role of lubrication, sealing and cooling.
(5) The influence of the failure of suction and discharge valves of the compressor on the displacement. Metal fragments or other foreign matters fall between the valve seat and the valve plate, and the valve is not tightly closed, resulting in air leakage. This not only affects the air displacement, but also affects the change of interstage and temperature. The loose contact between the valve seat and the valve plate results in air leakage, which affects the air displacement. One is the manufacturing quality problem, such as the valve plate warping, and the other is the serious wear of the valve seat and valve plate.
2. Causes of abnormal exhaust temperature
(1) The exhaust temperature is abnormal. Theoretically, the factors that affect the increase of exhaust temperature are inlet temperature, pressure ratio and compression index (k = 1.4 for air compression index). In fact, the factors that affect the high suction temperature are: low intermediate cooling efficiency, or more scale in the intercooler will affect the heat transfer, then the suction temperature of the later stage must be high, and the exhaust temperature will also be high. If the pressure ratio is higher than the normal value, the exhaust temperature will increase. In addition, water-cooled machines, water shortage or water shortage will make the exhaust temperature rise.
(2) Abnormal pressure and reduced exhaust pressure. If the air volume discharged by the compressor can not meet the flow requirements of the user under the rated pressure, the discharge pressure must be reduced. Therefore, the decrease of the discharge pressure is a phenomenon, and the essence is that the discharge volume can not meet the requirements of the user. At this time, we have to replace another machine with the same exhaust pressure and large displacement. The main reason for the abnormal interstage pressure is the air leakage of the air valve or the worn piston ring. Therefore, we should find out the causes and take measures from these aspects.
(3) Overheating fault. In the crankshaft and bearing, crosshead and sliding plate, packing and piston rod friction, the temperature exceeds the specified value is called overheating. The consequences of overheating: one is to speed up the wear between the friction pairs; the other is that the heat accumulated continuously leads to the burning of the friction surface and the burning and holding, resulting in serious accidents of the machine. The causes of bearing overheating are as follows: the bearing and journal fit unevenly or the contact area is too small; the bearing is skewed, the crankshaft is bent, the lubricating oil viscosity is too small, the oil circuit is blocked, the oil pump is out of order due to fault, etc.; during installation, there is no leveling and clearance, the main shaft and motor shaft are not aligned, and the two shafts are inclined.