Charge Pump

What Is a Charge Pump?

A charge pump is usually a centrifugal or positive displacement pump used to “charge” or feed another pump (like a high-pressure pump) with the necessary inlet pressure to avoid cavitation. It's a specialized type of pump used to maintain pressure and flow in fluid systems, especially in applications requiring a consistent supply to downstream components. In simple terms, charge pumps “feed” other pumps or systems—ensuring there’s always a stable volume of fluid available, often under pressure.

In fluid handling equipment, a charge pump helps prevent cavitation, maintain system efficiency, and improve equipment longevity. These pumps are essential in setups like hydraulic systems, mud pumping operations, and horizontal directional drilling (HDD), where continuous, pressurized fluid is a must. Whether you’re working in industrial processing, oil and gas, or construction dewatering, charge pumps play a vital supporting role that keeps everything running smoothly.

How Does a Charge Pump Work?

Unlike pumps that move fluids for end use, a charge pump primes or maintains conditions for other system pumps. Its core function is to supply fluid at the right pressure and flow rate so that the main pump—often a mud pump, centrifugal pump, or positive displacement pump—doesn’t run dry or suffer from suction-related problems.

Charge Pump Flow:

1. Fluid Source – Charge pump pulls fluid from a tank or reservoir.

2. Pressurization – Pump increases fluid pressure to meet system requirements.

3. System Feed – Fluid is fed into another pump or into a pressurized loop.

Because they’re part of closed-loop systems, charge pumps often support fluid handling in cooling, hydraulic, or HDD operations—making them indispensable in precision-demanding industrial environments.

Charge Pump vs Other Pump Types

Charge Pump vs Centrifugal Pump

Centrifugal pumps move high volumes of clean fluid with moderate pressure. Charge pumps feed systems like centrifugal pumps to prevent cavitation.

✅ Use centrifugal pumps for high-flow tasks.

✅ Use charge pumps to supply steady pressure to downstream equipment.

Charge Pump vs Diaphragm Pump

Diaphragm pumps are chemically resistant and can handle aggressive, viscous fluids. Charge pumps maintain pressure, not chemistry.

✅ Use diaphragm pumps for dosing or chemical transfer.

✅ Use charge pumps to support systems that need fluid pre-feed.

Charge Pump vs Positive Displacement Pump

Positive displacement pumps deliver exact volumes and handle thick fluids. Charge pumps ensure those pumps always have fluid to draw.

✅ Use PD pumps for accurate flow.

✅ Use charge pumps to prevent dry-run scenarios.

Other relevant comparisons:

• Grinder Pumps cut and transport solids in sewage—different than pressure support.

• Peristaltic Pumps deliver sanitary or abrasive fluid flow, often in metering applications.

• Trash Pumps move debris-laden water quickly but aren’t suited for pressure feeding.

Applications of Charge Pumps

Charge pumps are critical to a range of fluid processing equipment across industries. Common applications include:

• Mud Circulation in HDD: In horizontal directional drilling, charge pumps feed drilling fluids to mud pumps, preventing pressure drops or flow interruption.

• Hydraulic Systems: Keep hydraulic circuits pressurized to improve response time and prevent air ingestion.

• Water and Wastewater Processing: Supply pressurized flow to treatment equipment or booster systems.

• Well Pump Replacement Systems: In remote areas, charge pumps stabilize pressure in systems where wells feed into surface or storage tanks.

• Industrial Mixing & Dosing: Ensure flow consistency when supplying process lines or secondary metering systems.

In these roles, charge pumps are often used alongside mud pumps, trash pumps, grinder pumps, and centrifugal pumps, forming a complete fluid handling solution.