What are the common causes of premature stator wear in screw pumps?

2025-10-13 11:16:35

Common causes of premature stator wear in screw pumps include the following:

Abrasive wear: This is one of the main forms of stator wear in screw pumps and is categorized as dry abrasive wear and wet abrasive wear. Wet abrasive wear occurs when a liquid medium exists between the abrasive particles and the rubber, while dry abrasive wear occurs when no liquid medium exists between the abrasive particles and the rubber. Abrasive wear causes the stator rubber surface to gradually peel away.

Erosive wear: Also known as erosive wear, this is caused by fluid flow between the screw pump rotor and stator. Under normal operating conditions of the screw pump, erosive wear is also a major form of stator wear. Continuous fluid impact leads to the gradual loss of stator material.

Fatigue wear: Fatigue wear occurs when the friction and contact stress between the stator rubber and the blunt mating surfaces on the rotor are not high. Although this type of wear is relatively low in intensity, it can still cause significant wear to the stator rubber over time.

Friction wear: Friction wear occurs when the friction coefficient is high and the rubber's tear strength is low. During this process, the rubber surface is torn, curled, stretched, and detached, forming curled rubber fragments. Especially in the case of a screw pump operating in dry friction, the friction between the rotor and stator generates heat, which increases the temperature of the rubber and reduces its tear strength, thereby exacerbating frictional wear.

Dry or semi-dry operation: Operating a screw pump in dry or semi-dry conditions results in direct contact and excessive friction between the stator rubber and the rotor, accelerating wear.

Foreign matter intrusion: If foreign matter is in the pump body, it may scratch or cut the stator rubber surface, accelerating the wear process.

Excessive medium temperature: Long-term operation in high-temperature media can cause the stator rubber material to age and harden, reducing its wear resistance.

Excessively large solid particle diameter: If the pumped medium contains solid particles of excessive diameter, they may impact and cut the stator rubber, accelerating wear.

To reduce premature wear of the screw pump stator, the following measures can be taken:

Ensure that the screw pump is fully filled with medium; avoid dry or semi-dry operation. Regularly inspect and remove foreign matter from the pump body.

Control the medium temperature and solid particle size.

Select a stator rubber material with good wear resistance.

Perform regular maintenance and servicing on the screw pump, including checking coaxiality, tightening bolts, and lubricating.