The noise of the yhb main oil pump usually refers to the noise level measured under extreme vacuum when the pump is stable. It includes the noise of the pump itself and the motor noise. It is also concerned with the noise during the start-up phase when the pump temperature is not stable and the noise at different inlet pressures, as well as the noise during the operation of the open gas town. The design of the yhb main oil pump to reduce pump noise during the production process yhb main oil pump noise, usually refers to the noise level measured under extreme vacuum when the pump is stable. It includes the noise of the pump itself and the motor noise. It is also concerned with the noise during the start-up phase when the pump temperature is not stable and the noise at different inlet pressures, as well as the noise during the operation of the open gas town. Therefore, consider a variety of influencing factors.
In terms of the location of the sound, the noise of the pump has the following possible aspects:
(1) the impact of the gear on the cylinder, the residual volume of the pump and the sound of the pressure oil in the exhaust dead space;
(2) the impact of the exhaust valve plate on the valve seat and the support member;
(3) The echo and bubble bursting sound inside the box;
(4) bearing noise;
(5) Noise caused by a large amount of gas and oil impacting the oil deflector;
(6) Others. Such as noise caused by the transmission, fan noise of the air-cooled pump, etc.
(7) Motor noise, which is a crucial factor.
The recommendations for the design and treatment plan are described as follows:
1. The impact of the gear on the cylinder wall.
If the design, manufacture or improper use of materials causes the gear to slip poorly, or because of the exhaust dead space, the incompressible oil causes the gear head to not always follow the cylinder wall, which will cause the impact of the gear on the cylinder wall. Therefore, it is preferable to use a circular arc surface to separate the structure of the intake and exhaust ports. Use the exhaust guide to eliminate dead space. When using the line separation structure, Botaibang should minimize the distance from the exhaust end point to the tangent point. For the gear pump below 70L/s, consider the actual thickness of the gear. It is recommended to take 7~10mm, and the large pump takes a large value. When it is too close, due to the existence of the rotor gear groove and only one narrow belt contact of the gear head, once the gear is turned to the cutting point position, the sealing effect is not good, which will affect the pumping speed and even the ultimate pressure of the pump. It can be seen that this structure can not completely eliminate the exhaust dead space, which limits the level of noise reduction.
It should be pointed out that the gap between the gear and the groove is too large to reduce the performance. Therefore, to ensure reasonable tolerance and shape tolerance values, pay attention to the thermal expansion of the gear, avoid gear and groove pulling, pay attention to the oil's cold oil viscosity, design enough gear spring force, when using the circular arc surface separation, the rotor center The additional eccentricity value should not be too large. Otherwise, the gear passes through two circular arcs, which will produce a tendency to break away from the cylinder wall at the intersection, and instead cause impact noise. Generally, the small pump can be 0.20~0.25mm, and the large pump can be appropriately increased.
The pressure oil in the exhaust dead space and the sound of the pressure oil in the residual volume. When the pump reaches the limit pressure, the two pressure oils will be directed to the vacuum chamber at high speed when they are connected to the vacuum chamber, and the sound is struck against the rotor and the cylinder wall. The size and position of the two volumes are related to noise.
2. The amount of gas sucked by the valve plate against the valve seat and the support member is large, the pump has a large amount of circulating oil, the valve noise is larger, the valve jumps high, the valve area is large, the valve piece noise is also large, and the valve material is large. It also has a certain impact. Rubber diaphragms should have better noise than steel sheets or laminates. To this end, to control the amount of oil, the valve should be closed in a timely manner, to be strict. Pay attention to the selection and structure of the valve.
3. When the echo and bubble burst in the tank increase, the noise will increase. Therefore, this noise will increase significantly when the gas is opened or when the atmosphere is passed. If the gas ballast capacity is adjustable, the gas ballast amount can be adjusted reasonably.
4. Noise emitted by a large amount of gas and oil when impacting parts such as oil baffles. If the part is not rigid enough or is not tightened, vibration and collision will increase the noise. Therefore, the oil baffle should not only have sufficient rigidity and tightness, but also, when it is required to contact other parts (such as the fuel tank), the rubber can be used to avoid the collision noise caused by vibration and improve the oil retaining effect.
Http://news.chinawj.com.cn
Editor: (Hardware Business Network Information Center) http://news.chinawj.com.cn