Exposure to the elements can wreak havoc on drill rigs. CREDIT: SCHRAMM
Canada’s climate ranges across temperature extremes and combines with humidity and precipitation to constantly threaten the integrity of heavy outdoor equipment like drilling rigs. Protecting this equipment from the elements can vastly extend the rig’s productive life.
Drilling rigs and equipment are fabricated from multiple materials, all of which are susceptible to damage from exposure to a variety of climate conditions because of the fundamental laws and principles of physics and chemistry. As such, protections against the elements are applied to rigs during the manufacturing process, but ongoing preventive maintenance and other efforts are necessary to prolong the rig’s integrity and the capital investment in the equipment.
Rigs in Canada must endure a number of fluctuating harsh conditions. Scorching summer temperatures. Punishing UV rays from sunlight. Oppressively high humidity. Parching levels of low humidity. Heavy winds. And water in various forms, including snow, sleet, ice and acid rain. Frequently, several of these extremes combine. Over time, all of these conditions threaten the rig’s integrity.
Corrosion, an electrochemical process, occurs when metal is in contact with an electrolyte, such as water. With relative humidity of 60%, the metal will be in contact with an electrolyte.
Chemical reactions triggered by precipitation and humidity will inevitably lead to metal degradation following extended exposure.
Extreme cold temperatures can also make metal brittle, shortening fatigue life.
Polymers such as plastics used for seals and screens can become too flexible in heat and brittle in cold, making them prone to cracking and breakage.
Extremely arid conditions can peel the protective paint off of metal.
Continued and heavy wind can damage the rig itself.
Hydraulic fluids subjected to extreme cold become viscous and congeal. At that point, they can starve components of lubrication prior to start-up, which can damage metal and lead to less efficient operations and possibly catastrophic failure.
Preventing such a failure is a matter of physics, or ensuring energy into the system equals the energy exiting the system.
If a metal cylinder in extreme cold conditions is not heated to operating temperatures before it begins operating, that cylinder simply cannot perform as efficiently as it would if it had been pre-heated.
There are many ways to defend a rig against the elements.
The process starts during rig design with materials selection, moves through the manufacturing phase with the application of protective coatings, and continues throughout the operational life of the rig.
Coatings such as paint guard metals from the elements to prolong the rig’s operational life. Paint seals the metal off from potential damage from corrosion and UV radiation. Coatings insulate materials from absorbing or radiating energy, so they simultaneously protect the metal from degradation while also protecting humans from burns caused by bare metal exposed to sunlight for extended periods.
Coatings like lubricants protect equipment such as pumps and engines from wear due to friction as well as from seizing during operations.
Following proper handling methods will help keep a rig in top operating conditions even when facing harsh temperatures.
For example, in periods of deep cold, bringing equipment up to operating temperatures prior to starting the equipment will prolong the equipment’s life. Avoiding shock loads by smoothly transitioning equipment into operation will also help keep the equipment in good condition.
Keeping the rig clean not only contributes to safety and efficiency in the workplace but also helps prevent environmental damage from occurring to the rig while extending the service life of equipment. Removing moisture from surfaces helps stave off opportunities for corrosion to take hold. Removing dust and dirt from the surfaces prevents them from entering into sensitive equipment and damaging it. Clean equipment promotes the effectiveness of visual inspections by making it possible to clearly diagnose what service and repair work is needed. From an opex perspective, equipment such as hydraulic cylinders will deliver an extended service life when hydraulic cylinder rods are kept clean.
Preventive maintenance helps keep at bay the wear and tear caused by normal operating conditions as well as any damage caused by environmental conditions. Such maintenance includes periodically repainting the rig to shore up protection against corrosion and changing out hydraulic fluids and seals.
Other preventive maintenance activities that can prolong the productive life of equipment includes the periodic inspection and replacement of filters, lubricating mating surfaces, periodically applying UV ray-blocking solutions to polymers, and testing lubricants and coolants at regular intervals.
Inspections are critical to extending the operational life of a rig that must survive in a range of extreme climates and conditions.
Frequent and routine non-destructive testing inspections will identify defects in protective coatings and the rig itself before they have a chance to cause serious damage. Visual inspections can catch obvious defects. Ultrasonic testing inspects the internal structure of equipment, making it possible to detect changes in material thickness, cracks, voids and other structural defects.
Radiographic testing also inspects the internal structure, and the X-rays or gamma rays can travel through steel, concrete and ceramics.
If an inspection flags a problem, the rig operator can schedule repair work for the rig.
Another way to protect drilling rigs – active or idle – from the elements is to shelter the rig from damaging conditions. Because drilling rigs are large, it would be cost-prohibitive to erect a structure to cover the rig. However, using tarps to protect surfaces that need to be protected from the elements will minimize the reach and effects of damaging conditions on the rig.
Many pieces of equipment come together to make up a drilling rig, and they are all at the mercy of Mother Nature. Infrequent maintenance and neglect will rapidly diminish its functional life while diligent maintenance and adherence to proper handling procedures will prolong the functional life of the investment.
Eric Mosley is the director, aftermarket, for Schramm Inc. For more information, see www.Schramminc.com.