Batley Valve® BV 30000 – Varidiff Vane

Our Varidiff trim provides a solution to the problems of cavitation and noise generated by conventional butterfly valves due to their inherent high pressure recovery.

General Details

Varidiff trim incorporates two hemi-spherical control elements on opposite sides of the vane to reduce the pressure recovery particularly at low openings: a value of 0.9 is achieved compared with 0.7 for a standard vane. Further efficacy is achieved by adding an integral baffle. For higher openings the pressure drop is broken down across the vane and the baffle plate which results in a reduction in pressure recovery. The flow characteristic is equal percentage with a turn down in excess of 100:1. Due to the low dynamic torque a stable mode of operation is maintained 5 and 80 degrees opening.

Key features/benefits

  • Reduces problems in potentially cavitating services
  • Extensive range of body & trim options


  • Back pressure control on overboard dump lines in the offshore industry
  • Other applications include firewater ring system control valve, brine blowdown control, jetty loading valves, sea-water drain and re-circulation, cooling water circulation, and distulate to culvert valves
  • In addition to the above liquid service applications it has also found use on steam vent headers, and gas pipelines, for low noise requirements


  • Low noise (Power)
  • Low noise (Industrial)
  • Oil and gas production
Design standards

API 609, BS 5155, MSS SP68, API 598, BS 6755, FCI 70.2, ANSI B16.34, ISO 5752, DIN 3202

Design ratings

ASME 150

Size range/-dimensions

100mm to 1200mm (4″ to 48″)

Pressure class/-power rating N/A
Temperature range

30°C up to 220°C (86°F to 428°F)

Capacity Up to 26000


All castable materials: Carbon Steel, Stainless Steel, Duplex, Super Duplex, Hastalloy, Inconel, Monel, Titanium, etc.

Trim Materials: Austenitic SS,17-4 PH, Duplex/Super Duplex SS, Various hard surfaces to seat & seal ring available (stellite, tungsten carbide).


  • Material Reinforced Aluminium/Bronze