Oil-free ball valve for high-criticality HVAC applications

The new OFB series is a hermetic ball valve designed for oil-free chillers and heat pumps, aimed at improving suction-side reliability in critical applications such as data centers and advanced HVAC systems.

Technology context and relevance
Oil-free systems are increasingly adopted in industrial refrigeration and HVAC due to advantages in energy efficiency, maintenance, and sustainability. However, refrigerant migration and pressure losses on the suction side remain technical challenges. The OFB valve is introduced to strengthen system protection and optimize flow behavior in configurations using high-speed centrifugal compressors.

Functional design and technical architecture
The OFB integrates three functions in a single component: smooth suction cone transition, hermetic isolation, and full motorization capability. The suction cone optimizes inlet flow quality with negligible pressure drop, while the ball valve prevents refrigerant migration during shutdown and startup, contributing to system stability.

The series is modular and compatible with Turbocor TGx and TTx compressors, with flanged inlet options of 3", 4", and 5". It supports an operating temperature range from -40 °C to +100 °C and complies with global connection standards including ANSI, ASTM, DIN, and EN, simplifying integration into new and existing systems.

Actuation and operational reliability
The valve can be paired with compact MQT electric actuators with a 10-second response time and brushless motors. The stem sealing system, reinforced with guide bearings and a top-mounted support, reduces misalignment and mechanical wear. The valve-actuator assembly has been validated through endurance testing of up to 100,000 cycles to ensure long-term reliability.

Applications and operational benefits
The OFB is intended for data centers, advanced HVAC installations, and industrial refrigeration systems where oil-free technology is used to improve energy efficiency and reduce maintenance. The design contributes to refrigerant circuit stability, refrigerant control, and integration into oil-free cooling architectures for critical thermal infrastructure environments.

Positioning within the oil-free portfolio
The OFB valve complements the Danfoss EXO program alongside other oil-free components such as OFC valves and PTS stabilizers. The strategy aims to expand the ecosystem of components compatible with oil-free centrifugal compressors, with a focus on efficiency, reliability, and operational sustainability.

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