FIELD: oil industry. SUBSTANCE: sucker-rod well pump has cylinder with sucking valve, plunger with a delivery valve, rod with a coupling, discharging unit, and coupling unit. The discharging unit consists of housing with the inner conical surface inside which there are radial openings arranged over periphery and used for flowing fluid when the pump is lowered. The housing is in communication with the cylinder and pump-compression pipes through couplings. The discharging device is provided with a conical bushing the outer side of which is cylindrical and provided with radial openings and conical groove between them. Inside the conical bushing is a through step opening with grooves at its smaller diameter. The coupling unit consists of a housing-centralizer with inner conical side wherein conical threading die are arranged over periphery and used for gripping and holding the step core by the thread. The core is connected with the plunger through coupling and rod. Inside the housing-centralizer is a washer and spring that, being assembled, is compressed by a special member screwed in the housing-centralizer. The special member has a through opening with a thread for coupling with the pump rod moving the dia inside it when it is moved by the step core when it engages the wedge- shaped threading dies thus does not allowing them to be separated out of the housing-concentrator when the pump is lowered into a well. There is also a radial opening for displacing fluid when the die holder moves. EFFECT: enhanced efficiency and reliability. 1 dwg
