Following a lightning strike, the ENSCO 8505 drilling rig in the Gulf of Mexico was about to stop drilling. Damage to the crown mounted compensator (CMC) cylinder, a device used to apply a constant tension to the drillstring and compensate for any rig movement, required repairs to prevent cylinder seal leaks, and lost hydraulic fluid.

As one of the seven rigs in the ENSCO 8500 Series, that has a reputation of exceptional uptime performance contributing to Ensco’s No. 1 rating in customer satisfaction by EnergyPoint, an independent survey firm, the company required a speedy solution to maintain high-operational standards.

Removing and replacing the damaged CMC cylinder from the platform would be expensive, and cost the rig operator thousands of dollars with every hour of lost production. Ensco, National Oilwell Varco (NOV) and SIFCO Applied Surface Concepts (ASC) came together to solve this problem. The companies found a solution with SIFCO ASC’s plating process, using SIFCO’s AeroNikl 7280 for corrosion protection, and Cobalt 2043 to cap the repair for hardness to protect against surface wear. The SIFCO Process involves a portable method of electroplating localized areas without the use of an immersion tank. The final result was extremely successful. The repaired cylinder was dimensionally accurate to 0.001" tolerance as compared to the 0.005" tolerance NOV originally requested.

Today’s Energy Solutions (TES) sat down with SIFCO ASC Southwest Territory Sales Manager, Tony Arana, to uncover more about this repair, and how other companies can use SIFCO ASC’s services.

Today’s Energy Solutions: What did NOV need to communicate to SIFCO for the operation to be successful?

Tony Arana: Typically, each application is unique to the company, but the basic information we need consists of any existing requirements from the customer. Such requirements include applicable specification, base material, desired deposit, purpose of the deposit, and thickness required. We also have a service checklist that we complete for every job to ensure all pertinent information is gathered and no critical steps are missed prior to the service.

TES: Can you describe the SIFCO ASC plating process using SIFCO’s AeroNikl 250 (SIFCO Process Code 7280) used in the NOV situation?

TA: It Is the combination of the base material and the final electroplated deposit to be applied that determines the preparatory process (the steps prior to plating the final deposit). Each base material has preparatory steps that are required to achieve good adhesion of the electroplated deposit. These steps are outlined in the SIFCO Process instruction manual. Each process began with masking the component to localize the deposit to the affected area. That area was then cleaned and etched with preparatory solutions to ensure the best adhesion of the desired deposit. In the case of NOV it was AeroNikl 250. The deposit was then applied with a solution – soaked anode (brush) via a flow system to ensure a consistent and even application.

TES: Why was the SIFCO ASC plating process using SIFCO’s AeroNikl 250 (SIFCO Process Code 7280) chosen for this project?

TA: AeroNikl 250 is widely used in the oil & gas industry because of its corrosion protective properties. The rig is currently out in the Gulf of Mexico in a very corrosive environment.

TES: What were some of the challenges for this project?

TA: Since the oil rig is out in the Gulf of Mexico, SIFCO ASC was positioned to be able to repair the damage in place. The SIFCO Process is designed for on-site repairs, and the equipment and solutions can typically be carried in a suitcase-sized kit. When undertaking the repair work for NOV, two SIFCO ASC technicians were located near the top of the derrick, 250ft up. Their expertise in electroplating and the SIFCO Process ensured a safe and efficient repair, all while in a daunting position.

TES: How long did it take to get the CMC running?

TA: It took the technicians a total of 24 hours to complete the work. If NOV resorted to disassembling the shaft, the repair could have taken up to three months to complete. SIFCO not only saved NOV time on their repair, but the costs associated with downtime as well.

TES: How did SIFCO manage to complete this repair so quickly?

TA: Not only are our technicians trained for situations in the field, the plating solutions used in the SIFCO Process are special electrolytes with metal contents substantially higher than those of standard tank plating solutions. Selective plating is typically 50x to 60x faster than tank plating. Also, in this situation, other repair applications would have required disassembly and long downtimes.

TES: How do SIFCO’s solutions help its customers close the gap in corrosion costs associated with oil exploration?

TA: Selective plating is a fast and cost-effective alternative to more time-consuming and costly repair alternatives such as cladding and chromium deposits. We offer multiple deposits for various repairs, refurbishment, and OEM applications such as:

  • Silver plating onto dynamic sealing and bearing surfaces
  • Selective plating of copper onto premium threaded connections, alloy premium drill pipe, risers, tubulars, and couplings to prevent galling during make-and-break operations
  • Application of AeroNikl (sulfamate nickel) for corrosion protection in high-chloride, down-hole applications
  • Repair of worn and mechanically damaged surfaces with a combination of copper and AeroNikl

We also provide coatings for various industries beyond oil & gas, such as automotive, power generation, marine, and aerospace. The SIFCO Process also allows us to anodize and electropolish localized areas in place or in shop.

Typical applications for SIFCO ASC in the energy sector include silver plating palm assemblies, damper windings, copper wedges, and strips; and the coating of shafts and engine components.

We apply deposits for:

  • Lowering electrical contact resistance
  • Improved wear resistance
  • Improve corrosion resistance
  • Pre-braze
  • Anti-galling
  • Surface hardness
TES: What steps do companies need to take before contacting SIFCO if an emergency like NOV’s arises and throughout the repair process?
National Oilwell Varco’s Ensco 8505 drilling rig in the Gulf of Mexico

TA: Unfortunately, NOV’s situation was due to an unforeseen lightning strike. But before critical or emergency surface treatments are needed a customer can maintain wear and damaged areas using the SIFCO Process.

There are three ways to use the process: our technicians will perform the repair on-site, or in one of our job shops, or we can train your staff to perform the process at your facility. Standard and custom workstations are available, as well as semi- and fully-automatic plating systems.

SIFCO Applied Surface Concepts

www.sifcoasc.com

National Oilwell Varco

www.nov.com

Ensco plc

www.enscoplc.com

About the author: Arielle Campanalie is the associate editor of TES and can be reached at 216.393.0240 or acampanalie@gie.net