Traditional repair methods
Repair and maintenance of hydrocarbon processing equipment is typically performed using one of two very different methods.
This first method is planned repair. Equipment will be scheduled to go offline and be out of usable service for the fix. Purging, cleaning, and vapor-freeing activities will take place before the actual repair starts. Oil refineries, chemical plants, storage facilities, paper mills, and loading terminals will typically schedule planned outages on their process equipment based on very specific criteria.
The criteria include equipment fowling, inspection data, thermo-cycling, known metal fatigue life cycle analysis, and regulatory and safety requirements. To complete the actual repairs and upgrades, traditional and specialty welding processes are used.
These shut downs are costly due to lost margin, replacing equipment which was run to failure due to the lack of proper in-service maintenance procedures.
Unlike the first, this method is not scheduled. In order to do this, the plant must either perform an unplanned outage on the equipment, or initiate repairs while the equipment remains in service. Completing repairs on equipment without removing service first is commonly referred to as making an online repair.
Repairs that have not been scheduled, by definition, are a result of conditions leading to a need for repairs that were unknown, over-looked, or deferred until a later date. The repairs are typically done using liquid polymer cold patch solutions.
Typical in-service cold patching is used primarily as a temporary solution in order to get that equipment to the next planned outage. Looking at the time and resources used to patch and wait until a planned outage, plus the lost margin on that tank while it is out, the cold patching solution can be much more expensive in the long run. Although most of the time, a long-term solution is more ideal in terms of safety and cost, there are times when using cold patching is necessary, as to the timing of a planned outage.
The history of forge bonding
Forge bonding is a proven, solid-phase, metal joining process that produces very high-strength, metal-to-metal joints. It is a derivation of rotary forge welding, a well-proven manufacturing process which has been used for more than five decades by industries such as aerospace, automotive, and heavy construction.
In its generic form, this process is generally accomplished by use of large, in-place machine tools for joining materials, with extreme or mission-critical product applications, as well as joining similar, dissimilar, and exotic materials.1
Forge bonding, in its earliest portable form, was first introduced in the 1990s as a means of utilizing this reliable, solid-phase joining process in remote or situation work locations.
This includes marine, offshore, and underwater applications. The process has since been identified as having significant potential for use in situation work locations where traditional joining methods, such as arc welding and other fusion methods, are impractical or environmentally prohibited. This issue is common to offshore platforms and petrochemical process plants.2
More important to application usefulness, the forge bonding process has been consistently demonstrated and documented within the industry as a safe process for use on live pipelines, and within identified hazardous or explosive environments, without creating a source of ignition.3, 4, & 5
More recent advancements in portable forging equipment designs and joining methodologies has improved the strength and reliability of the process results, while lowering operating temperatures to improve safety.
Currently, specialized application tools and equipment are available to address a wide range of industrial work site applications that benefit from this process, as opposed to more traditional fusion welding methods. This is especially important where open flame, and high-process temperatures are prohibited, such as Zone 1 areas on offshore rigs, and production platforms.6