Fisher D4 Compact High-Pressure Globe Control Valve

Fisher D4 compact high-pressure globe control valve

The Fisher D4 is a compact, rugged globe valve intended mainly for high-pressure throttling with either a pneumatic or an electric actuator. It was designed for oil and gas production, where it controls pressure and flow on high-pressure separators, scrubbers and similar process equipment, and it copes well with liquids and gases that are gritty, sticky or inclined to build up on internal parts. The body is offered in NPS 1 and NPS 2 with screwed or flanged connections up to CL1500, and the same valve can be fitted with a spring-to-close or spring-to-open diaphragm actuator or with the Gen 2 easy-Drive electric actuator. Seven Star LLC supplies Fisher D4 valves in Oman and the GCC as an independent supplier in Muscat; the data below follows the Fisher D4 product bulletin (D103039X012, April 2023).

D4 technical specifications

Actuator choices for the D4

Pneumatic actuator

The pneumatic actuator is a diaphragm type with an effective area of 452 cm² (69 sq in.), a maximum casing pressure of 3.4 bar (50 psig) and 1/4 NPT connections. It is supplied as spring-to-close (fail down) or spring-to-open (fail up), with a temperature range of −40 to 93 °C, and the materials were selected for cold-climate and low-temperature use. Diaphragm and O-rings are made of chloroprene and HNBR.

Gen 2 easy-Drive electric actuator

The electric option suits remote wellsites without instrument air. It runs on 11 to 30 V DC, consumes less than 0.1 watt-hour per operation, and accepts dry-contact, 4 to 20 mA or Modbus RTU control signals, as on/off (snap-acting) or positioning (flow or pressure control) versions. Nominal stroke speed is 3.9 mm/s at 24 V DC. Enclosure rating is Type 4X and IP66, and ambient temperature range is −20 to 70 °C with no heater. The hazardous-area approvals listed include CSA Class I Division 1 explosion-proof, ATEX flameproof (II 2 G Ex db IIA T6 Gb) and IECEx flameproof. An optional RPU-100 reserve power unit sets the loss-of-power position through Modbus. The actuator calibrates by simply stroking the valve open and closed.

Design features that help in service

• Hammer-nut bonnet: trim and packing are serviced by removing the deep-bore hammer nut and lifting the actuator and bonnet away, without taking the body out of the line and without dismantling the actuator.
• Safer bonnet joint: pins in the bonnet push the bonnet clear while threads are still engaged, adding protection if the joint is opened under residual pressure.
• Heavy-duty guiding and a screwed seat ring that fully encloses the seat gasket; the seat ring can be removed with a standard socket.
• Integral bonnet flange without snap rings, which avoids snap-ring failure in sour or corrosive atmospheres.
• Quick-change plug held by a removable groove pin.
• Tungsten carbide trim for sand, solids and erosive production fluids.

Selecting a Fisher D4 valve

Work through the operating envelope: throttling or on/off duty, pressure-reducing or back-pressure use, fluid type, normal and maximum temperature, flow rates and the full range of pressure drops, including the maximum drop at shutoff. Compare this with the bulletin pressure-drop tables for the selected port and trim. Decide pneumatic or electric actuation based on instrument air availability and fail action, then choose class, end connection and trim: standard, sour NACE or tungsten carbide. The bulletin includes environmental limits for sour trim, so give H₂S partial pressure and chloride content in the enquiry.

Installation and maintenance

The D4 may be installed in any position, though normally the actuator is vertical and above the valve. Make sure the arrow on the body matches process flow (flow up). Screwed bodies have compact face-to-face dimensions for tight skids. Valve plug travel is 19 mm and the packing is live-loaded to reduce adjustment. For low-emission sites the Quad-O compliant ENVIRO-SEAL packing supports leak-detection programs. A digital valve controller or electric positioning actuator completes the loop.

D4 applications in Oman and the GCC

Typical uses are wellhead choke-adjacent pressure control, high-pressure separator level and pressure control, scrubber dump valves, gas lift and chemical injection lines, and small-bore high-pressure letdown on gas processing skids. The electric easy-Drive version is attractive at remote desert locations where only solar power or low-voltage DC is available, while tungsten carbide trim extends service life where sand production is expected.

Related Fisher products

Seven Star LLC also lists the Fisher easy-Drive electric valve actuator, and the 1052 and 1061 actuators for rotary valves. For positioners, see the FIELDVUE DVC2000 and DVC6200.

Information to send with an RFQ

• Fluid, phase, flow rates, inlet pressure and pressure drop, shutoff differential and temperature.
• NPS, pressure class and end connection type.
• Trim: standard, sour (state standard edition) or tungsten carbide.
• Actuator: pneumatic fail-up or fail-down, or electric (on/off or positioning, control signal, supply voltage, hazardous-area requirement).
• Emission requirements and ambient temperature range.

Documents and quotation

The Fisher D4 product bulletin is attached to this page as a datasheet. Send the data above and we will confirm a matching construction and prepare a quotation.