GENERAL CHARACTERISTICS
 
DAVINCI PRESSURE DIFFERENTIAL CONTROL VALVES are hydraulically operated diaphragm valves designed to maintain a preset differential pressure between two selected points of a hydraulic system. The valve continuously monitors pressure conditions and automatically adjusts its opening to preserve the required pressure difference, even when flow demand or system pressure varies.
Their principal advantage is the ability to provide stable and automatic differential pressure control without external power. By preventing excessive or insufficient pressure differences, the valve contributes to the correct operation of pumps, filters, heat exchangers, cooling circuits, distribution branches, and other pressure-sensitive equipment. This improves hydraulic balance, protects system components, and helps reduce unnecessary energy consumption.
 
The valve is supplied in sizes from DN50 to DN800 mm and incorporates a high-strength ductile iron body engineered for demanding water-service applications. All iron components are treated with a fusion-bonded epoxy coating, ensuring effective corrosion protection and dependable performance throughout an extended service life.
 
Its operating assembly consists of a top- and seat-ring-guided stem combined with a flexible diaphragm system, providing precise movement, stable regulation, and reliable response to changing pressure conditions. The nylon-reinforced diaphragm offers excellent resistance to repeated operating cycles, while the stainless steel seat and disc-retainer ring provide corrosion resistance and durable sealing performance.
 
The valve delivers drip-tight shut-off when complete closure is required. Its globe-style body configuration provides smooth modulation and accurate control throughout the operating range, helping prevent sudden pressure changes and unstable hydraulic behaviour.
A differential-pressure pilot senses the pressure at the designated control points and continuously regulates the main valve position. This enables the valve to maintain the selected pressure differential automatically, reducing the need for manual adjustments and ensuring consistent performance under variable load conditions.
The valve has been developed to simplify inspection and servicing. Internal components can be accessed and maintained without removing the valve body from the main pipeline, minimizing service interruptions, labour requirements, and maintenance costs.
 
DAVINCI PRESSURE DIFFERENTIAL CONTROL VALVES are suitable for municipal water networks, pumping stations, industrial plants, irrigation installations, HVAC and cooling circuits, water treatment facilities, mining operations, high-rise buildings, and fire protection systems. Typical applications include maintaining differential pressure across pumps, filters, heat exchangers, control circuits, distribution zones, and parallel pipeline branches.
Manufacture and performance comply with EN 1074-5, with design and testing carried out according to BS EN 1074-5, ISO 5208, BS EN 12266-1, and BS EN 558-1. Flanged connections are available in PN10, PN16, PN25, and ANSI Class 150, while face-to-face dimensions conform to EN 558-1, Series 1.
 
Designed for water applications, the valve is available with pressure ratings of 1.0 MPa, 1.6 MPa, and 2.5 MPa and is suitable for operating temperatures from −10 °C to 80 °C. Pressure testing is conducted according to EN 12266-1, Leakage Rate A, including a body test at 1.5 × PN and a seat test at 1.1 × PN. Applicable requirements of the EU Pressure Equipment Directive 2014/68/EU are observed according to the valve size and product category.
 
A complete range of differential-pressure pilots, filters, pressure gauges, isolation valves, sensing lines, and control accessories is available for adaptation to specific system requirements. Optional V-Port trim can improve regulation under low-flow operating conditions, while a double-chamber design may be supplied for specialized applications. Please consult the factory for customized pressure settings, alternative operating conditions, or specific system configurations.