大型推弯式弯管机超低恒速液压控制系统研究

摘要

In order to obtain the high quality of large-diameter and thin-wall bend , the bending of pipes can be realized by the in-termediate frequency induction heating the hydraulic push-bending style pipe bender , but the ultra-low and constant speed control in the push-bending style pipe bender is one of the key technical problems for assuring the quality of large-diameter and thin-wall bend. Based on the analysis of the creeping phenomenon for hydraulic cylinder , started from the actual working condition , the ultra-low and constant speed control of the system was realized by using the digital hydraulic control technology to avoid the low speed creeping phe -nomenon in bending process .The result proves that the system can ensure low speed stability of the hydraulic cylinder , and avoid the phenomenon of vibration and curved wrinkle during the bending process , so it is easy to be used in engineering practice .%为了获得高质量的大直径薄壁弯头,通过中频感应加热液压推弯式弯管机对管材实现弯制,而超低恒速控制是大型推弯式弯管机保障弯头质量的关键技术问题之一.从实际工况出发,在分析油缸爬行问题的基础上,通过数字液压技术的阀控实现系统的超低恒速,避免弯制过程的低速爬行现象.结果表明:系统保证了油缸的低速稳定性,避免了弯制过程出现颤动及弯弧起皱现象,并易于为工程实际所用.