Hydraulic cylinder mainly includes cylinder, piston rod, cylinder head, piston, which cylinder head materials will be different because of the level of pressure, generally low pressure castings, low pressure with HT300 gray iron, high pressure with 35, 45 steel. When the cylinder head itself is the guide sleeve of the piston rod, the cylinder head is cast iron. At the same time, brass, bronze or other wear-resistant materials should be fused on the guide surface. If the guide sleeve is pressed into the cylinder head, the guide sleeve shall be wear-resistant cast iron, bronze or brass.
The commonly used materials of cylinder piston are wear-resistant cast iron, gray cast iron (HT300, HT350), steel and aluminum alloy, and the coaxial tolerance value of piston and piston rod should be 0.03mm. The cylinder is commonly made of No. 20, 35 and 45 seamless steel pipes, which are honed or rolled to achieve a roughness of less than 0.4μm. The low pressure cylinder can use 20 steel pipe, and the high pressure cylinder can use 45 steel pipe.
The piston rod has two kinds of solid rod and hollow rod. One end of the hollow piston rod needs to be set aside for welding and heat treatment with air holes. The solid piston rod material is 35 and 45 steel, and the hollow piston rod material is 35 and 45 seamless steel pipe. After rough machining, the piston rod is conditioned to 229~285HB in India, and then the hardness is 45~55HRC after high-frequency quenching.
For hydraulic cylinder, hydraulic oil is also very important, hydraulic oil is the hydraulic medium used in the hydraulic system that uses liquid pressure energy, and hydraulic oil is indispensable for the normal operation of the cylinder, so the use of oil is very important. However, it should be noted that before starting, check the oil level and check whether the opening of each oil circuit is in the correct standby state.
The machine runs at idle speed for about 5min, check whether there are bubbles in the oil of the level gauge. If it is a new car or a new hydraulic oil, it is normal for bubbles to appear in the oil label during idle speed, and the machine can only be allowed to work after the bubbles disappear. At the same time, pay close attention to the temperature of the oil, when the hydraulic cylinder works for a period of time, if the oil temperature is too high, it is recommended to stop and rest, and then work again after the oil temperature is normal, in order to increase the service life of the system and oil.
