The Nature and Purpose of Flush Pumps

A means to handle the transfer of liquids is among the most common requirements across a wide range of industries. In most cases, the solution is to provide a pipeline to hold the liquid and some suitable pumping equipment to generate enough pressure to keep it moving. The pump’s design will tend to vary according to the type of fluid it must handle, but, at their heart, several types employ a rotating shaft enclosed by mechanical seals at the inlet and outlet points to prevent leakage. Frequently, flush pumps are a necessary precaution to ensure the long-term integrity of those seals.

The Role of Flush Pumps

In effect, these units are a form of built-in secondary pumping device whose purpose is to augment the performance of the larger type of pump typically used in many heavy industries. These machines can tend to run hot and are frequently used to handle hot liquids. They are also subject to damage caused by frictional forces. It is possible to overcome both problems by subjecting the mechanical seals to a steady stream of water under pressure. The role of flush pumps is to create that stream. Their part is to deliver a coolant, often deionised water, to the seals and thus prevent overheating, which might otherwise lead to premature failure. In other situations, the water may be necessary to wash the seals free of any particles that might cause abrasion and subsequent leaks.

To ensure that the vulnerable mechanical seals receive adequate protection at all times, flush pumps need to deliver a constant flow. Some models are self-regulating. These have the means to adjust their flow rate automatically in response to variations in the system pressure.

While centrifugal pumps are among those used most frequently, they are not suited to every task. Instead of rotating impellers, some models employ pistons or plungers. Sometimes these units must withstand high temperatures and corrosive substances. Also, in industries such as pharmaceuticals and food processing, exceptional hygiene is essential. In these cases, the plungers and pistons are often ceramic. In such applications, the flush pumps, which are also plunger-based, provide a means to maintain their seals’ integrity and deliver alternative coolants for use in high-temperature applications.

Bestline Manufacturing

Maintaining the integrity and prolonging the working life of the mechanical seals on a pump is essential in many different industrial applications, particularly those within the mining and oil and gas sectors. The Johannesburg-based company, Bestline Manufacturing, supplies an extensive range of world-class flush pumps and related accessories to meet their specialised needs.