On the other hand, the actual pre-torque screw can not be too large, that is, the actual pre-torque generated by the actual prestressing force can not have Great. 另一方面，螺紋的實際預緊扭矩又不能過大，也即由實際預緊扭矩產生的實際預緊力不能過大。
The results show that decreasing the driving voltage, primitive cavity, pre-tightness force of spring, and the mass of mobile elements can improve the performance of solenoid. 通過降低驅動電壓，減小初始氣隙，降低彈簧預緊力，減輕電磁閥運動部件的質量，均可以提高電磁閥的性能。
