Ｄ、限位器D, limiting device限位器为一个底部带限位板和流通通道的短节，接在定子的尾部，其作用是施工作业时给转子限位以防止下入过头而失去作用和杆柱脱落时防止杆柱掉入井底。The limiting device is a short section with bottom limit plate and distribution channel, which is
莫诺
Ｄ、限位器D, limiting device限位器为一个底部带限位板和流通通道的短节，接在定子的尾部，其作用是施工作业时给转子限位以防止下入过头而失去作用和杆柱脱落时防止杆柱掉入井底。The limiting device is a short section with bottom limit plate and distribution channel, which is connected to the tail of the stator. Its function is to limit the rotor to the rotor during ctruction1, so as to prevent it from falling into the overhead and lose its function and prevent the rod from falling into the bottom when the rod string falls off.
Ｆ、抽油杆F, sucker rod所使用的抽油杆是常用的普通抽油杆、空心抽油杆和连续抽油杆，可根据油井确定。The sucker rod used is commonly used as a common 1sucker rod, hollow sucker rod and continuous sucker rod, which can be determined according to the oil well.Ｇ、定子扶正器G, stator centralizer定子扶正器为有一定弹性的笼形装罩，每一对由两半构成，中间大、两端小。作用是使定子居中和减小定子的摆动。The stator centralizer is a cage shaped cover with a certain elasticity. Each pair is made up of two halves, large in the middle and small at both ends. The function is to make the stator middle and reduce the stator wobble.Ｈ、锚定装置H, anchoring device对于没有封隔器的井和泵挂深度浅的井，用于固定定子、消除摆动和防止定子脱扣。采用普通的锚定装置即可。For wells without packers and shallow wells with deep pumps, it is used to fix the stator, eliminate the swinging and prevent the tripping of the stator. A common anchoring device can be used.
单螺杆泵有以下优点：
1)因为泵内的回转部件惯性力较低，故可使用很高的转速;
2)结构坚实，安装保养容易;
3)单螺杆泵的压力和流量范围宽阔。压力约在3.4-340千克力/cm2，流量可达18600cm3/分;
4)单螺杆泵的吸入性能好，具有自吸能力;
5)与其它回转泵相比，对进入的气体和污物不太敏感;
6)流量均匀连续，振动小，噪音低;
7)单螺杆泵的运送液体的种类和粘度范围宽广。
单螺杆泵的缺点是，螺杆的加工和装配要求较高;泵的性能对液体的粘度变化比较敏感。
（作者： 来源：）
