Flush Pumps for High-Temperature or Low-Lubricity Liquid Handling

Flush pumps are used for applications involving low-lubricity or high-temperature liquids. These units are plunger based and come with a manifold system that is configured to include an inlet and outlet. What sets these pumps apart from other types is that apart from the inlet and outlet ports, the units feature flushing ports.

We offer an extensive range of Cat Pumps, and units are able to handle low-lubricity, high-temperature, and high-pressure.

Role of The Flushing Port

It is for liquid circulation between the high and low-pressure seals. This helps to prolong the lifespan of the seals, as well as to reduce the need for maintenance.

Main advantages include:

  • Prolonged seal lifespan.
  • Low maintenance.
  • Compatibility with a wide range of liquids.
  • Safer operation.

Differences Between Standard and Plunger Applications

The manifold on the flush-style type also features the inlet and outlet port as is the case with the standard plunger. The unit features the flush port that facilitates the circulation of liquids between the high and low-pressure seals. This, as explained earlier, helps to increase the durability of the seals and thus reduce the need for maintenance.

These units are used for deionised water applications because the units can handle low lubricity liquids well. The units are also used for liquids at higher temperatures, such as glycol or boiler feed water.

Standard plunger pumps work at a maximum liquid temperature of between 59°C and 83°C, model dependent. Because units can handle a wider range of temperatures and liquids, the units can be used for a wider range of applications. Because these units can handle higher temperature liquids, it helps prolong the seal life and thus lower ongoing maintenance requirements. Of course, the ability to handle higher temperatures while protecting the seals also provides for a safer operating environment.

For liquids at temperatures of up to 115°C, special seals can be fitted to ensure safe operation. Other types of liquids can be used when the liquids are chemically compatible with the wetted parts, as well as the pumped liquid. Note that the liquids should have some type of lubrication characteristic to protect the seal life.

It is essential to follow the manufacturer guidelines in the operation of the pumps. For one, keep in mind that the flow rate can be higher if the high-temperature liquids such as boiler feed water or similar liquids are pumped. When the flush is used for unit cooling, it is essential to ensure sufficient flow in order to reduce the heat and thereby maintain an acceptable operating temperature. The unit must not be operated outside its maximum temperature range. Cat Pumps offer the cast manifold and block manifold types. The cast types have model numbers that end with “C” while the model numbers that end with “K” indicate the block types.

Get in touch with our team in Johannesburg for more information about our range of flush-style plunger pumps for applications such as boiler feed or deionised water pumping.