Eliminating Refrigerant Leakage - GRAT Electric 3-Way Ball Valve in Central Air Conditioning Centrifugal Chiller Refrige

Application Background

With the acceleration of urbanization, large commercial complexes and industrial facilities increasingly demand higher stability and energy efficiency from central air conditioning systems. A renowned air conditioning manufacturer, in its new generation of centrifugal chiller projects, required a key valve capable of precisely and reliably switching refrigerant flow directions to control the unit’s operating modes and energy regulation. The core customer requirement was that the valve must maintain zero leakage over the long term in a mixed medium containing refrigerant oil and withstand frequent start-stop cycles. The GRAT electric three-way ball valve series, with its specialized design for harsh working conditions, was successfully selected and applied in this chiller system.

Operating Conditions

• Application: Central Air Conditioning Centrifugal Chiller Unit
• Industry: Eco-friendly Refrigeration
• Medium: Gas-Liquid Mixed Refrigerant (containing refrigerant oil)
• Product: GRAT Electric Three-Way Ball Valve (L-Port Flow Path)
• Size: DN125
• Body: CF8
• Ball: CF8
• Seat Seal: PTFE + HNBR O-ring Composite Seal
• Temperature: -30 to +60 °C
• Pressure: PN1.6 MPa
• Control Signal: AC220V Switch Signal
• Commissioning Date: September 2010
• Design Life: 5 to 8 years

Product Advantages & Features

Addressing the specific working conditions of centrifugal chiller refrigerant systems, the GRAT electric three-way ball valve demonstrates the following core advantages and characteristics:

1. Exceptional Sealing Performance:

   • Utilizes a composite valve seat of PTFE and HNBR. PTFE provides an extremely low friction coefficient and excellent chemical resistance, while the HNBR O-ring ensures elastic compensation capability across a wide temperature range (especially under low-temperature conditions). This dual protection achieves hermetic zero leakage against the refrigerant medium.

2. Robust and Durable Structural Design:

   • Both the valve body and ball are made of CF8 stainless steel, offering excellent structural strength and corrosion resistance. This enables the valve to withstand the system pressure of PN1.6 MPa and long-term erosion from the oil-containing medium, ensuring structural integrity under pressure fluctuations.

3. Precise and Reliable L-Port Flow Path Switching:

   • The three-way L-port flow path design is optimized for fluid diversion and mixing scenarios, perfectly matching the centrifugal chiller’s control logic for refrigerant flow direction. The electric actuator responds quickly with sufficient torque, ensuring the valve moves rapidly and accurately into position upon receiving the AC220V switch signal, achieving disturbance-free flow path switching.

4. Broad Operational Adaptability:

   • The valve design fully considers the low-temperature start-up environment of -30°C and operational temperatures up to 60°C. The selected materials maintain stable performance within this temperature range, avoiding the risk of seal failure due to low-temperature embrittlement or high-temperature aging, making it particularly suitable for full-range operation of refrigeration systems.

Performance Results

Since its commissioning in September 2010, this GRAT electric three-way ball valve has demonstrated performance exceeding expectations:

• Operational Reliability: Throughout its service life, the valve has not caused any system downtime or refrigerant leakage incidents attributable to the valve itself. It achieved a 100% actuation accuracy rate, ensuring the continuous and stable operation of the main unit.
• Service Life: The valve’s actual trouble-free operation time far exceeded the designed lifespan of 5-8 years, showcasing the foresight and high reliability of GRAT’s product material selection and structural design, delivering exceptional value and return on investment for the customer.
• Customer Feedback: The customer highly praised the “Set-and-Forget“ reliability of the GRAT valve, recognizing it as a key component ensuring the competitiveness of their high-end centrifugal chillers in the market. It has subsequently been designated as a specified component in multiple follow-up projects.

GRAT electric three-way ball valve is a high-performance and reliable product in the field of eco-friendly refrigeration, particularly within central air conditioning centrifugal chillers where technical requirements and reliability standards are extremely high. GRAT remains committed to providing safe, efficient, and innovative solutions for global industrial fluid control.