How to select a progressive cavity pump stator for chemical and temperature compatibility

Describe the real medium, including changes over time

Give the exact liquid name, formulation, concentration and temperature range. For blends, waste streams, sludge or process residues, describe all important components rather than naming only the main liquid. Include cleaning and flushing fluids because they contact the stator even when they are not part of normal production.

State whether the medium can cause elastomer swelling, hardening, softening or extraction of additives. When existing plant experience with a particular elastomer is available, provide it as supporting evidence, but still check whether the new concentration and temperature are the same. Compatibility from one duty should not be transferred automatically to another.

The G progressive cavity pump moves liquid through sealed cavities formed by the rotor and stator. This close interaction makes material condition central to performance. Rotor material, stator elastomer and sealing arrangement should therefore be selected together.

Then review the mechanical load on the stator

High viscosity or solids may require lower speed and special attention to the inlet. A pump that is starved of liquid can lose lubrication and cooling at the rotor-stator interface. Do not try to correct poor inlet filling only by changing the stator material.

A progressive cavity pump is positive displacement. If the discharge can be isolated or blocked, provide pressure protection appropriate to the system. The stator is not an overpressure protection device, and a stronger elastomer does not remove the need for a safe discharge arrangement.

Warning signs that require a duty review

An unexpected rise in torque or motor load can indicate increased viscosity, solids accumulation, stator swelling, blocked discharge or poor inlet filling. Reduced flow can result from wear, slip, speed change or suction problems. These symptoms should trigger an ordered inspection rather than an immediate material substitution.

Repeated stator damage calls for a review of liquid chemistry, temperature history, abrasiveness, running speed, discharge pressure and dry-running events. Check whether cleaning fluid or shutdown storage exposes the elastomer to a condition absent from the original inquiry.

Dry running is especially important because the pumped liquid normally supports cooling and lubrication at the rotor-stator interface. Use the related dry-running protection guide to review level, flow, temperature and operating interlocks.

Create a stator selection record before quotation

1. List process, cleaning and flushing fluids with concentration ranges.
2. Record normal and maximum temperatures and expected contact time.
3. Provide viscosity at operating temperature, solids and abrasiveness.
4. State minimum, normal and maximum flow plus discharge pressure.
5. Describe suction level, inlet pipework and operating schedule.
6. Identify rotor, stator and seal materials proposed for final review.

Use the progressive cavity screw-pump range to compare available configurations. Final material and drive selection remains conditional on the verified operating information.