综采液压支架高可靠性油缸接头座焊接方案研究

Research on Welding Scheme of High Reliability Oil Cylinder Joint Seat of Fully Mechanized Mining Hydraulic Support

为改善综采液压支架油缸漏液问题,提升液压支架可靠性,对液压支架油缸接头座焊接结构、油缸材料的金相及化学成分进行分析,从焊接设备、焊接工艺等方面进行研究,使用不同焊接参数、不同焊前预热温度进行试验,发现使用肯倍X8焊机1-MIG焊接模式,焊接电流260 A、焊接电压28 V,27SiMn、30CrMnSi焊前预热温度分别为200℃、300℃时,可以使焊缝有效深度提升95%,焊接接头可以获得较好的焊缝外观,按照ISO 9015检验最高硬度可以分别降低至253HV、351HV。为验证此焊接方案的可行性,选择2套产品共642件立柱进行焊接验证,经VT、MT探伤合格后,随机抽取20支立柱按照GB 25974.2进行中心过载性能试验、耐久性试验,油缸接头座焊缝漏液率为0。应用此焊接方案可以显著降低液压支架油缸接头座漏液率,大幅提高设备可靠性。

In order to improve the problem of the liquid leakage of fully mechanized mining hydraulic support cylinder and improve the reliability of hydraulic support,the welding structure of hydraulic support cylinder joint seat and the metallographic and chemical compositions of cylinder materials were analyzed.Researched the welding equipment and weld processes,used different welding parameters and preheating before welding preheating temperatures to conduct experiments,and found that with Kemppi X8 welding machine 1-MIG welding mode,welding current 260 A,welding voltage 28 V,when 27SiMn and 30CrMnSi pre-welding preheating temperature is 200 C and 300℃respectively,the welded joint can obtain larger weld penetration and better weld appearance,and the highest hardness tested according to ISO 9015 can be reduced to 253HV and 351HV respectively.In order to verify the feasibility of this welding scheme,a total of 642 columns of two sets of products were selected for welding verification.After the welding passed the VT and MT flaw detection,20 columns were randomly selected for central overload performance test and durability test according to GB 25974.2,liquid rate is O.The application of this welding scheme can significantly reduce the leakage rate of the hydraulic support and greatly improve the reliability of the equipment.