Dynex Checkball Piston Pumps

Never Mix, Never Worry:

Eliminating Cross-Fluid Contamination

Heeding the colloquial advice "never mix, never worry" can be an advantage when selecting water glycol pumps for your system.

Using Dynex single-fluid pumps eliminates concern about the water glycol becoming contaminated by the oil from a separate lubrication circuit. With no lubricating oil, you'll never worry about cross-fluid contamination.



7 Reasons to Use Single-Fluid Pumps:

1 Environmental Safety

Dynex checkball pumps use the water glycol for internal bearing lubrication. This single-fluid design reduces environmental concerns by removing the need for a secondary pump oil on the platform.


The single-fluid design avoids the need and cost for regular maintenance of a separate lubricating circuit. This makes these pumps ideal for unmanned, remote platforms.

No Fluid Degradation

With no separate lubrication circuit required, glycol and oil cannot combine to form a potentially damaging mixture. This prevents fluid degradation, providing longer component life. See "Mayonnaise Effect" at right.

Low-Cost Installation

Eliminating a separate lubrication circuit reduces space and piping costs. These single-fluid pumps are easier to handle and install than other designs.

Long-Life Operation

The checkball pump design isolates the pistons from system pressure during startup. This requires lower starting torque providing longer bearing life.

Smaller and Lighter

The checkball pump design provides a high horsepower-to-weight ratio. These pumps can be less than half the size, weight and cost of a triplex or plunger pump.

Vertical Mounting

Checkball pumps can be installed in a water glycol reservoir – not easily done with other pumps with a separate lubrication circuit. Internal lubricity passages in Dynex pumps ensure adequate bearing lubrication, for long service life in vertical mounted applications.



Dynex single-fluid water glycol pumps for oil & gas applications

High pressure capability and compatibility with water glycol make these pumps ideal for wellhead safety controls systems and other offshore oil & gas applications. See specifications on Dynex water glycol pumps.


What is the
"Mayonnaise Effect"?

Oil and glycol do not mix together to form a solution. Instead, water glycol combined with lubricating oil can form an emulsion. The process is similar to that used to make mayonnaise.

While mayonnaise can be an appealing condiment, contaminated water glycol is not good for your hydraulic system.

Left unchecked, this contaminated mixture promotes the growth of bacteria, yeast and other microbes. Air in the system can accelerate this process.

This resulting degraded fluid resembles a light brown or green mayonnaise, with a sour odor.

Growing bacteria also produces waste products that can deteriorate metals. Under some conditions, the bacteria can create a semi-solid mass that can seriously degrade system performance and destroy components.

The solution, of course, is to use Dynex single-fluid pumps. Then you can enjoy your mayonnaise on a sandwich where it belongs.