Atlas Unloading Valve 75KW for Air Compressor Parts 1614915500

An Unloading Valve is a critical pressure control component primarily used in hydraulic and pneumatic systems. Its primary function is to divert pump flow to a tank (reservoir) at little to no pressure when system pressure reaches a predetermined setting. This allows the pump to "unload," significantly reducing power consumption, minimizing heat generation, and extending the life of the pump and system components, all while maintaining system pressure through an accumulator or other means.

• Energy Efficiency & Cost Savings: The primary benefit. By unloading the pump during low-demand periods, it eliminates the energy waste and heat generation associated with constant flow across a relief valve, leading to substantial reductions in electricity costs.
• Heat Reduction: Prevents excessive fluid heating by minimizing the need to dump high-pressure fluid across a relief valve, which maintains optimal fluid viscosity and extends the life of seals and other components.
• Pump and System Protection: Reduces wear and tear on the pump by allowing it to run at near-zero pressure during idle cycles, significantly extending its service life.
• Pressure Maintenance: Can maintain a preset system pressure using an accumulator as a stored energy source, allowing for rapid response to demand without constant pump operation.
• Durable Construction: Built from high-strength materials like carbon steel, ductile iron, or stainless steel with hardened trim to withstand high pressures, pressure spikes, and continuous cycling.
• Multiple Control Options: Available in various pilot control types:
  • Direct-Acting: Simpler design for smaller flows and lower pressures.
  • Pilot-Operated: The most common type for higher flows and precise pressure control with minimal pressure override.
• Flexible Functionality: Can be configured as a simple unloading valve or as a dual-function unloading/relief valve, providing both primary system protection and energy-saving unloading.

The valve operates automatically between two states:

1. Loading (Pump Under Load):
   • System pressure is below the valve's cracking pressure setting.
   • The valve remains closed, allowing pump flow to be directed to the system to perform work.
2. Unloading (Pump Unloaded):
   • When system pressure reaches the valve's set point (e.g., via a remote pilot signal or an internal spring setting), the valve spool shifts.
   • This creates a flow path that diverts the entire pump output directly back to the tank at very low pressure (just enough to overcome line resistance).
   • The pump is now "unloaded," operating efficiently while the accumulator maintains system pressure.
3. Re-Loading:
   • When system pressure drops below a certain level (due to an actuator moving), the unloading valve closes.
   • Pump flow is again directed to the system to replenish the accumulator and perform work.

Unloading valves are essential in systems with variable flow demands:

• Hydraulic Power Units (HPUs): The most common application, for machines with intermittent cycles like presses, clamps, and injection molding machines.
• High-Low Pump Circuits: Used with two pumps--a high-pressure, low-flow pump and a low-pressure, high-flow pump--to unload the large pump at high pressure.
• Accumulator Circuits: Essential for charging and maintaining pressure in accumulator-based energy storage systems.
• Testing Rigs: To unload the pump between test cycles.
• Pneumatic Systems: In large compressed air systems to unload compressors and manage network pressure efficiently.

• Precision Pressure Control: Engineered for accurate and stable pressure settings with minimal override (the pressure increase required to open the valve fully), ensuring efficient system operation.
• High Flow Capacity & Low Pressure Drop: Designed to handle full pump flow with minimal resistance when open, maximizing energy savings.
• Robust & Reliable Design: Built for millions of cycles in demanding industrial environments, ensuring long-term reliability and reducing the risk of unplanned downtime.
• Application Expertise: Our team provides expert support to help you select the right valve size, pressure setting, and control option (internal or external pilot) for your specific system.
• Energy Savings Focus: By providing precise control, our valves directly contribute to lower operational costs and a reduced carbon footprint, offering a rapid return on investment.