"Eleventh Five-Year" period, the forecast total domestic demandvalve 345 billion.
“十一五”期间，预测国内阀门的需求总量为345亿元。
2
According to the drive mechanism and the demand of the hydraulic rock drill, the structure character and the designing ways of the impact device, control valve and supporting arm were introduced.
根据水压凿岩机液压传动原理和使用要求，详细介绍了凿岩机中冲击器、操纵阀和支腿的结构特点和设计方法。
3
The article introduces the characteristic and demand of LPG carrier tanker safety valve, and discusses emphatically the design, making and debug for lead-down spring safety valve and its structure.