1, see if the shock absorption is smooth, that is, press it by hand, whether it can be pressed to the end, and whether there are any irregularities in the process of pressing.
2, look at the damping of shock absorption, it is impossible to press it by hand like a spring, once pressed, it will go down, and once it is loose, it will rebound directly. It should be compressed slowly and bounced back slowly.
3. Look at the tightness of shock absorption. After bouncing back, see if there is any oil stain on the chrome-plated surface, that is, whether there will be a rainbow under the light; Then there is whether there is oil around the sealing ring.
4, look at the manufacturer's brand and workmanship.
Hydraulic type
Hydraulic shock absorbers are widely used in automobile suspension systems. The principle is that when the frame and axle move relatively and the piston moves back and forth in the cylinder of the shock absorber, the oil in the shock absorber shell repeatedly flows from one cavity to another through some narrow holes. At this time, the friction between the liquid and the inner wall and the internal friction of the liquid molecules form a damping force for vibration.
inflatable
Inflatable shock absorber is a new type of shock absorber developed in 1960s. Its structural feature is that a floating piston is installed at the lower part of the cylinder, and a closed air chamber formed by the floating piston and one end of the cylinder is filled with high-pressure nitrogen. The floating piston is equipped with an O-ring with large cross section, which can completely separate oil from gas.
Extended data:
Matching skills of shock absorber
First, check whether the product provides elevation requirements of 2-3 inches. Some products only provide an elevation of 2 inches. After barely using the elevation angle of 3 inches, it is easy to pull to the limit in cross-country and cause damage.
Second, whether the diameter of the central telescopic rod of the shock absorber can reach 16 mm or more is a basic index of strength.
Thirdly, whether the upper and lower connecting sleeves of the shock absorber are high-strength polyurethane sleeves is also an important basis to ensure long-term high-strength use, because ordinary rubber is difficult to use for a long time under high strength.
The shock absorber is mainly used to suppress the shock of spring rebound after shock absorption and the impact from the road surface. When passing through the uneven road surface, although the damping spring can filter the vibration of the road surface, the spring itself will reciprocate, and the shock absorber is used to suppress this spring jump.
Reference link: Baidu Encyclopedia _ Shock Absorber