- Home
- Categories
- Process Control
Instrumentation & Control
Process Control
Process control equipment is the command layer of a drilling rig. It covers the driller's cabin and chairs, operator screens and local joystick stations, and the programmable logic controllers (PLCs), I/O and networks that run machine logic underneath. On used control hardware, the firmware revision, the application program and the licences decide what the unit is worth as much as its physical condition.
How the three sub-Categories divide the control system
The group splits by layer, from the operator down to the logic.
| Sub-Category | What it covers | Usual reason to source it used |
|---|---|---|
| Drilling control systems | Driller's chairs, cabin servers, zone management and the network to each machine controller | Sister-rig upgrade, reactivation, or a cabin from a rig leaving service |
| Control panels and HMI | Operator screens, joystick consoles, local control stations, purged panels | Like-for-like replacement of a failed station |
| Automation systems | PLC CPUs, racks, remote I/O, network modules and engineering software | Spares for a controller family the OEM no longer sells |
Choosing the right level of replacement
Work from the fault, not the hardware. A dead touch screen or a worn joystick is a station-level swap, provided the replacement carries the same part number, revision and display project. A rig that has added a new top drive or pipe handler, or has run out of cabin spares, usually needs the drilling control system reworked as a whole. A CPU or I/O card that has left the OEM catalogue sends you to the automation layer, where the match is catalogue number, series and firmware.
Keep one rule in mind across all three. Control hardware is configured, not just installed. A used chair, panel or CPU arrives without your rig's application unless the Seller supplies the project files, and recreating them costs OEM engineering time.
Standards and class rules across the group
- IEC 61508 sets the design and certification rules for safety-related programmable electronics. IEC 61511 sets the user's duties for a safety instrumented system, from specification through proof testing and modification. Emergency stops and machine interlocks in a drilling control system often fall under one or both.
- The IEC 60079 series governs Ex equipment. Part 14 covers selection and installation, part 17 covers in-service inspection and maintenance, and part 19 covers repair and overhaul. Panels on the drill floor need ATEX or IECEx certification for their zone, gas group and temperature class.
- On classed units, DNV-OS-D202 covers automation, safety and telecommunication systems, and DNV-OS-E101 covers the drilling plant. ABS covers drilling systems in its Guide for the Classification of Drilling Systems (CDS). Class normally reviews any change to software or hardware in a system that carries a class notation.
- IACS UR E26 and UR E27 set cyber resilience requirements for vessels and for the computer-based systems on them. They apply to new construction contracted on or after 1 July 2024, so check with class how they treat control hardware moved onto such a unit.
Integration questions that cut across the group
- Software versions on every layer. A screen, a chair and a CPU each carry firmware that must work with the others.
- Network type and redundancy, such as Profibus, Profinet or EtherNet/IP, and whether the rig runs a ring or dual network.
- Power. Most control electronics run on 24 V DC from a UPS, and the UPS autonomy should match your rig's emergency power philosophy.
- Environment. Class type approval for marine control equipment includes environmental tests for vibration, temperature, humidity and electromagnetic compatibility, so check the approval covers the location you plan.
- Cyber security. PC-based servers and engineering stations need supported operating systems and patching, which older cabins often lack.
What matters most when sourcing it used
Control equipment ages differently from steel. A drawworks can run for decades with overhauls, while a controller family has a sales life, a spares life and then nothing. Before you commit, confirm the OEM lifecycle status of each part number, the licence transfer terms, and how the equipment was stored. Electrolytic capacitors and backup batteries age on the shelf, and humidity corrodes connector pins. Unused surplus from a cancelled newbuild is often the best source for a discontinued platform. Tested used hardware suits a spares store, and OEM-refurbished hardware with a fresh test report suits a critical position. Naventr can arrange an inspection on request and pass your technical questions to the Seller, who answers from their own records.
FAQ
Frequently asked questions
Can a used drilling control system be moved to a different rig?
Yes, but only with OEM engineering and recommissioning. The application software maps I/O, interlocks and screens to one rig's machines, so a different machine set means rework, a licence transfer, function testing of every interlock and emergency stop, and class review on a classed unit.
What documents should come with used rig control equipment?
Part numbers with hardware and firmware revisions, licence records, application program and configuration backups, Ex certificates, and the last function test report. For safety-related items, add the safety manual, the safety certificate and proof test records. Without the program backups, most control hardware is useful only as spares.
Are obsolete PLC parts worth buying for a drilling rig?
Yes, if your rig runs the same platform and no migration is planned in the next few years. Match the catalogue number, series and firmware to your installed hardware. Price the spares against a planned migration if the rig has a long contract ahead.
Do drill floor control panels need ATEX or IECEx certification?
Yes, any electrical equipment in a classified zone needs certification for that zone, gas group and temperature class. Zone 1 needs equipment protection level Gb or better, and Zone 2 needs Gc or better. Check each nameplate against the rig's hazardous area drawing.
Do IACS UR E26 and E27 apply to used control equipment?
They apply to new construction contracted on or after 1 July 2024, not to existing rigs by default. If you install used control hardware on a unit that falls under them, class may expect the E27 documentation and testing for that system, so confirm with class before you buy.
Looking for process control?
Tell us what you need and we will find out what is available. We reply within one business day.