How to Choose a Wellhead Control Panel: Pressures, Logic, Power and Testing

8 hours ago

3 min read

At a glance. Start a wellhead control panel (WHCP) specification from the valves it must operate. The subsurface safety valve (SCSSV) needs the highest hydraulic pressure, commonly up to 10,000 psi, while surface safety and wing valves need 3,000 to 6,000 psi. Then match the logic (pneumatic, electro-hydraulic, solar or PLC) to the power available at the site, decide whether one panel will serve one well or several, and fix materials, standards and the factory test before you ask for quotations.

What does a wellhead control panel do?

A WHCP supplies hydraulic pressure to hold a well's safety valves open and removes it to close them. On a shutdown it closes the valves in a set order: the wing valve first, then the surface safety valve (SSV), then the SCSSV deep in the well, so the safety valves close against a static well rather than full flow. Fusible plugs, high and low pressure pilots and ESD push-buttons all act through the same logic, so the panel's design decides how safely and reliably the well can be shut in.

Which pressures does the panel need?

Circuit	Typical supply pressure	What sets it
SCSSV (downhole safety valve)	Up to 10,000 psi; 15,000 psi for deep or high-pressure completions	Setting depth, shut-in pressure and valve opening pressure
SSV and wing valves	3,000 to 6,000 psi	Actuator size and wellhead pressure
Pneumatic logic and pump drive	80 to 150 psig instrument air or gas	Site utilities

Give the vendor the SCSSV opening pressure from the completion data sheet and the actuator data for each surface valve. The wellhead's API 6A pressure class, from 2,000 to 15,000 psi, sets the pressure the actuators work against.

Which logic and power suit the site?

Hydro-pneumatic – air- or gas-driven pumps and pneumatic logic. No electrical power is needed, which suits remote and unmanned wells.
Electro-hydraulic – electric pumps and explosion-proof solenoid valves, with signals to DCS or SCADA. Suits sites with power and a control system.
Solar-powered – low-power DC pumps and latching solenoids running from PV modules and a battery bank sized to the autonomy you need.
PLC or RTU-based – programmable sequencing, diagnostics and remote control, tested together with the hydraulics as one package.

One panel or several wells?

A multi-well panel serves a cluster from one hydraulic power section, with duty and standby pumps, accumulators and a control module for each well. Drawer-type modules let one well be serviced while the others keep producing. On pads with more than two or three wells this usually saves space, tubing runs and maintenance compared with separate panels, and it leaves room for wells added later.

Which standards and materials apply?

Safety logic normally follows API RP 14C / ISO 10418, with IEC 61511 when the hazard study assigns a safety integrity level (SIL). Wetted parts in sour service follow NACE MR0175 / ISO 15156, tubing follows ASME B31.3 and electrical equipment follows IEC 60079 for the hazardous zone. Enclosures and tubing are normally SS 316L, with 6Mo or Alloy 625 tubing for the most corrosive marine sites.

How should the panel be tested?

Ask for a factory acceptance test (FAT) that hydrostatically tests every hydraulic circuit to 1.5 times its design pressure, proves the shutdown sequence and closing times, checks every alarm and trip, and confirms pump and accumulator performance. Witness it if you can: faults are cheaper to fix in the workshop than at the wellhead.

Specification checklist

SCSSV opening pressure and setting depth for each well
SSV and wing valve actuator data and the wellhead's API 6A class
Number of wells now and planned
Logic type and the power available at site
Shutdown sequence, closing times and ESD inputs
Hazardous-area zone, ambient temperature range and sour-service requirement
Telemetry signals and protocol
FAT scope and witness points

Tech Inc. wellhead control panels

Tech Inc. builds hydro-pneumatic, electro-hydraulic, multi-well, solar-powered and PLC/RTU-based panels, with SCSSV supply up to 10,000 psi as standard and 15,000 psi on request, and every hydraulic circuit pressure-tested at FAT. Send your well data to mail@techincresearch.com for a P&ID, GA drawing and quotation.

Frequently asked questions

What pressure does an SCSSV need?

It depends on the setting depth and the well's shut-in pressure. Panels are commonly supplied for SCSSV pressures up to 10,000 psi, with 15,000 psi for deep or high-pressure wells.

Why does the wing valve close first?

Closing the wing valve first stops the flow, so the SSV and SCSSV close against a static well rather than flowing fluid. That protects their seats and extends their life.