管柱脱落的故障现象是：运行电流很低，基本上是电机的空载电流，除了有一股一股的气外，井口基本上无产液，正发循环时油套连通。The failure phenomenon of the string is: the running current is very low, basically the motor's no load current. Besides the gas with a single strand of gas, the wellhead basically has no liquid production, and the oil sleeve is connected when circulating.减少管柱脱落的措施有：将油管上扣扭矩由原来的值提高到值；采用油管螺纹垫片；定子上的装卸短节采用防松螺纹连接；采用油管锚或张力封隔器固定螺杆泵。The measures to reduce the falling off of the pipe string are as follows: increase the torque from the original value to the maximum value; use the oil pipe screw gasket; the loading and unloading joint on the stator is connected by loosening screw thread; and use the oil pipe anchor or tension packer to fix the screw pump.



定转子过早磨损Premature wear of fixed rotor定转子过早磨损主要是由于定转子的间隙过小引起的。The premature wear of the fixed rotor is mainly caused by the small gap between the fixed rotor and the rotor.油管与抽油杆柱磨损Oil pipe and rod string wear油管与抽油杆柱磨损的原因一是因为井斜抽油杆贴在油管壁上引起的，可以通过加抽油杆扶正器使抽油杆柱居中来减轻或消除，另一个原因是定转子不同心及转子的偏心运动造成的，在定子以上加一节内径较大的回转筒即可避免。Tubing and sucker rod wear reason is because the deviation of sucker rod attached to the tubing wall caused by heating, pumping rod centralizer make the rod center to reduce or eliminate, another reason is caused by the eccentric motion of the rotor and the rotor are not concentric, avoid a day the diameter of rotary cylinder in the stator can be larger than.

　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。

现将在现场采用同规格的G型单螺杆泵及齿轮泵在完全相同工况条件下并在输送出口压力为1 MPa时进行了简单的对比,测量了这样两组数据:当输送重油粘度约为75×102-6m2/ s时,齿轮泵出口压力表的指针跳动幅度为±0.16,三螺杆泵出口压力表的指针跳动幅度为±0.05,双螺杆泵出口压力表的指针跳动的幅度为±0.04 ;而当输送重油粘度约为150×102-6m2/ s时,齿轮泵出口压力表的指针跳动幅度为±0.22,三螺杆泵出口压力表的指针跳动的幅度为±0.06,双G型单螺杆泵出口压力表的指针跳动的幅度为±0.04。这说明,G型单螺杆泵在重油的输送和喷燃过程中,介质的输送压力很稳定。并且随着介质粘度的加大,G型单螺杆泵(尤其是双螺杆泵)的无脉动特点相比之下更为明显。