Oil and gas companies operating worldwide with both onshore and offshore facilities are confronted with the high cost and safety issues associated with retrieving corrosion monitoring and chemical injection equipment from their pipelines.
Pipeline corrosion can cause disastrous pipeline and assets failure that harm the environment, injure field operators, and lead to costly downtime. (Learn more about safety considerations in The Impact of the Pipeline Safety Act of 2011 on the Industry.) Therefore, it is important to periodically take measurements using corrosion monitoring coupons.
The Challenges of Offshore Corrosion Monitoring
Offshore production rigs are located many miles offshore, necessitating the transportation of operators and their equipment to a platform with limited living and storage space. (For more about corrosion in far away places, read Remote Corrosion Monitoring Systems in the Oil and Gas Industry.)
Traditionally, corrosion monitoring equipment installations required a three-person service team using a specialized tool to install and retrieve electrical resistance probes, corrosion coupons, and sample quills or chemical injection atomizers. The heavy extraction tool often weighed more than 150 pounds (68 kg) including the service valve and often required a jib-crane for safety.
With a heavy, awkward tool, retrieving corrosion monitoring and control devices in line pressures of up to 10,000 psi can be precarious, with the crew exposed to flammable and dangerous fluids. They can be injured if the tool is not properly operated, and using the tool at each point takes a significant amount of time.
Third-party companies that provide corrosion monitoring installation and retrieval service command high fees for this dangerous and labor-intensive operation, given that crews must maintain special certifications and be flown out to the platforms.
A desirable alternative are lighter weight insertion tools that can insert and retract tool holders for chemical injection and corrosion monitoring. These alternative insertion tools are rugged and durable but lightweight. Several high-profile oil and gas operators in Trinidad use these products on their facilities. These insertion tools place the tool holders for corrosion coupons, sample quills and chemical injection atomizers within the pipelines, and then are safely removed without venting or draining valuable product. System downtime is reduced as a side benefit.
The installations include a single- or double-block valve that permit one operator to install and retrieve a new corrosion coupon or service a sample quill or chemical injection atomizer in under five minutes. Compact insertion tools can be handled by one operator. Moreover, the tool holders do not require any service and maintenance once they are placed in the system.
The design of these new insertion tools is intended to make insertion and retraction under pressure safe, quick and easy, and cost effective, with only one tool needed to insert and retrieve corrosion monitoring and chemical injection tool holders into multiple adjacent pressurized systems. The tool is used only during the insertion or retraction operation and then is removed. Because the insertion tool can be operated easily by one person, oil and gas producers reduce manpower expenses and provide their crews with better quality tools and safety.
Corrosion monitoring tools should help platform owners determine whether their equipment requires maintenance or replacement, preclude disastrous leaks and system failures, extend asset service life and reduce expenses. Oil and gas producers have discovered that lightweight tools are faster and safer to use, which translates to a much lower cost of ownership. With these tools, platform operators can perform the corrosion coupon collection process by themselves to better control the process and reduce service costs.