1. The hydraulic cylinder of the oil pressure cutting machine has a rod cavity and no gas at low speed, which can achieve the purpose of exhaust by repeatedly running the hydraulic cylinder. If necessary, the two chambers of the hydraulic cylinder can set the exhaust device when the hydraulic system works.
2. The low-speed crawling caused by the improper design gap of the hydraulic cylinder can correctly design the sliding coordination gap between the hydraulic cylinder and the cylinder body, the piston rod and the guide sleeve. The theoretical coordination gap is H9 / N or H9 / f8 and H8 / f8. According to the experience of the author, the cylinder diameter and rod diameter of the hydraulic cylinder are from small to large, so design the coordination gap according to this, for larger cylinder diameter (? The coordination clearance of 200mm) and rod diameter (140mm) appears to be too large. In the actual process, the phenomenon of the hydraulic cylinder is more small cylinder diameter. The coordination clearance of the sliding surface of the hydraulic cylinder in foreign countries is generally designed as 0.05mm∽0.15mm. From the actual comparison results, the low speed crawling problem of the hydraulic cylinder is significantly improved. Therefore, this method is recommended for the hydraulic cylinder with large cylinder diameter.
3, cutting machine hydraulic cylinder guide element uneven friction of low speed crawling, it is recommended to use metal as a guide support, such as QT 500-7, ZQAL 9-4, such as non-metal support ring, it is recommended to choose in the oil size stability good metal support ring, especially the thermal expansion coefficient should be small, in addition, the support ring, need to strictly control the thickness of size tolerance and thickness uniformity.
4. Under the condition of working conditions, it is recommended that the composite sealing ring with PTFE is preferred, such as the commonly used lattice ring, special seal, etc.; for the lip seal, it is recommended to select the seal of fine rubber or similar materials, which has good following ability.
5. The impact of parts machining precision, In the process of the manufacture of the hydraulic cylinder of the oil pressure cutting machine, In particular, the geometric precision, Especially the lintactness is the key, In the domestic processing processes, The processing of the piston rod surface is basically the car rear grinding, Ensure that straightness is not problem, But for the processing of the cylinder block inner wall, There are many processing methods, There are boring-rolling, boring-honing, direct honing, However, because there is a gap between the basic level of domestic materials and the foreign materials, Poor straightness of pipe blank, Factors such as uneven wall thickness and uneven hardness, Often directly affects the straightness of the cylinder block inner wall after processing, Therefore, it is recommended to adopt the boring-rolling, boring-honing process, Such as the direct honing, First, the straightness of the pipe billet is improved.
Post time: May-15-2024