The tapered plug or "needle" is screwed in or out of a mating orifice in the body and thus controls the effective orifice size.
其锥形插头或“针头”是阀体上配置的螺纹旋进旋出的节流道，因此能够有效控制节流面积。
2
Methods Bacterial cultures were made on venipuncture needle, the puncture needle head of liquid bottle and the open site of rubber plug in intravenous transfusion.