Exploring Hydraulic Systems: Differences Between Open Center and Closed Center

Hydraulic systems are the lifeblood of many industrial and agricultural machines, providing the power necessary to perform a wide array of tasks. At the heart of these systems lies a crucial component: the hydraulic center. The design of the hydraulic center can significantly impact the efficiency, cost, and suitability of a system for specific applications.

Understanding Hydraulic Centers

Hydraulic centers are at the core of hydraulic systems, which are widely used in various industrial, agricultural, and mobile applications. Understanding hydraulic centers involves grasping the basics of hydraulic systems, the role of hydraulic centers in these systems, and the key differences between the two primary types of hydraulic centers: open center and closed center.

The Differences Between Open Center and Closed Center Hydraulic Systems

Basics of Hydraulic Systems

A hydraulic system uses fluid to transmit energy from one point to another. These systems consist of several components, including a reservoir for the hydraulic fluid, a pump to move the fluid, valves to control the flow and direction, and actuators (like cylinders or motors) to convert the fluid’s energy into mechanical force. The essence of any hydraulic system is the controlled movement of fluid under pressure.

Role of Hydraulic Centers

The “hydraulic center” in a system refers to the configuration of the control valve and how it manages the flow of hydraulic fluid. This center is crucial because it dictates how fluid moves through the system and how it returns to the reservoir. It plays a key role in controlling the operation of the hydraulic actuators, which perform the actual work, such as lifting, pressing, or turning.

Open Center Systems

In an open center system, when the control valves are in the neutral position, the hydraulic fluid flows in a continuous loop from the pump back to the reservoir through the center of the control valves. This design allows for a constant flow of fluid, irrespective of whether the actuators are in use or not.

Closed Center Systems

Conversely, in a closed center system, the control valves block the flow of fluid when in the neutral position. This means that the fluid flow stops completely unless a valve is opened to activate an actuator. This design often uses a variable displacement pump that adjusts the flow and pressure of the fluid based on the demands of the system.

Key Differences and Implications

The fundamental difference between these two types of systems lies in how they manage the flow of hydraulic fluid when the system is idle or when the actuators are not in use. This difference has significant implications for the system’s energy efficiency, complexity, and suitability for various applications.

  • Energy Efficiency: Closed center systems are generally more energy-efficient since the pump can reduce its output when no work is being done, whereas open center systems constantly circulate fluid, leading to potential energy wastage.
  • Complexity and Cost: Open center systems are simpler and usually cheaper to build and maintain. Closed center systems, with their more complex variable displacement pumps and control mechanisms, are often more expensive and require more sophisticated maintenance.
  • Application Suitability: The choice between open and closed center systems depends on the application’s requirements for control, efficiency, and cost.

Understanding hydraulic centers is fundamental to designing, operating, and maintaining hydraulic systems effectively. By selecting the appropriate type of hydraulic center, one can optimize the performance and efficiency of the hydraulic system for the intended application.

Open Center Hydraulic Systems

open center hydraulic

In open center systems, the hydraulic fluid continuously flows through the control valve, even in its neutral position. This design means that fluid returns to the reservoir through the center of the valve, creating a constant flow loop.

Characteristics of Open Center Systems:

  • Constant Flow Pump: These systems typically utilize a constant flow pump, which maintains a steady flow of fluid, irrespective of the workload or demand.
  • Less Energy Efficiency: Since the pump is always operating to maintain flow, open center systems can be less energy-efficient, especially when the hydraulic system is not performing any work.
  • Simplicity and Cost-Effectiveness: Open center systems are simpler in design and generally less expensive to manufacture and maintain, making them a popular choice for less complex applications.

Typical Applications:

  • Agricultural machinery
  • Small construction equipment
  • Other applications where continuous hydraulic flow is not critical

Closed Center Hydraulic Systems

closed center hydraulic

In contrast, closed center systems block the flow of hydraulic fluid when the control valve is in the neutral position. This design means that the fluid flow is halted until an operator actuates a valve.

Characteristics of Closed Center Systems:

  • Variable Displacement Pump: These systems often use a variable displacement pump that adjusts the flow of fluid based on system demands, providing fluid only when necessary.
  • Higher Energy Efficiency: Due to the on-demand nature of the pump, closed center systems are typically more energy-efficient, conserving power when the system is idle.
  • Complexity and Precision: Closed center systems are more complex but offer greater control and efficiency. They are generally more expensive both in terms of initial setup and maintenance.

Typical Applications:

  • Industrial machinery requiring precise control
  • Advanced mobile equipment
  • Systems where energy efficiency and control are paramount

Choosing Between Open and Closed Center Systems

The decision between an open center and a closed center system hinges on several factors:

  • Cost and Complexity: If cost is a limiting factor and the application does not require precise control, an open center system is often the preferred choice.
  • Energy Efficiency and Control: For applications where energy efficiency and precise control are critical, closed center systems are the better option.
  • Application Specifics: The nature of the machinery and its intended use play a significant role in determining the most appropriate system.
Choosing Between Open and Closed Center Systems

Choosing between open and closed center hydraulic systems is a critical decision that hinges on various factors including application requirements, cost considerations, energy efficiency, and system complexity. Here’s a guide to help in making this important decision:

Understand the Application Requirements

  • Precision and Control: If the application requires precise control over movements or pressure, a closed center system is typically more suitable. Its ability to provide variable flow and pressure offers better control.
  • Continuous or Intermittent Operation: For machinery that operates intermittently or needs hydraulic power in bursts, a closed center system is more efficient as it conserves energy when not in active use. Conversely, for applications where hydraulic power is needed continuously, an open center system may be sufficient.

Consider Cost Implications

  • Initial Investment: Open center systems are generally less expensive to install due to their simpler design and the use of constant flow pumps, which are typically cheaper than variable displacement pumps used in closed center systems.
  • Maintenance and Operational Costs: Closed center systems, while more expensive upfront, can be more cost-effective in the long run due to their energy efficiency and potentially lower maintenance costs, especially in high-demand applications.

Evaluate Energy Efficiency

  • Energy Consumption: Closed center systems are more energy-efficient because the pump provides fluid only when needed, reducing power consumption when the system is idle. This is crucial in applications where energy costs are a significant concern.
  • System Design Efficiency: Open center systems continuously circulate fluid, which can lead to energy wastage but can be more efficient in systems designed for constant use.

Assess System Complexity and Flexibility

  • System Complexity: Closed center systems are more complex and may require more sophisticated maintenance and understanding of hydraulics. This complexity can be a factor in environments where specialized skills are scarce or costly.
  • Flexibility in Expansion: If there’s a possibility of future expansion or modification of the hydraulic system, closed center systems offer more flexibility as they can easily accommodate changes in flow and pressure requirements.

Factor in Environmental Conditions

  • Operating Environment: In harsh or variable environments, the robustness of the system might be a key consideration. Closed center systems, with their sophisticated controls, might be better suited for extreme or fluctuating conditions.


Understanding the differences between open center and closed center hydraulic systems is crucial for selecting the right system for your needs. Each system has its advantages and disadvantages, and the choice largely depends on the specific requirements of the application. Whether it’s a simple agricultural implement or a complex industrial machine, the right hydraulic center can significantly impact performance, efficiency, and cost.


What Is The Difference Between Open And Closed Center Hydraulics? JANUARY 15, 2021 BY MARK

Share On
As a manufacturer and supplier with more than 20 years of experience, we are able to provide comprehensive and professional hydraulic product solutions. If you need support, please click the following button.

Read More Articles

Subscribe to Get Newest Update

Subscribe to get our latest insights, knowledge and experience. We will only send email when necessary. You may unsubscribe at any time.

All Your Request Will Be Replied Within 2 Hours

We'll send you the full details to your email

Rest assured, the protection of your email information is a top priority for us. We operate in full compliance with GDPR and CCPA, maintaining strict data security and privacy standards.