Pipeline corrosion control projects range from blasting and coating joints on new construction to pipe spools to repair and refurbishment of existing pipelines. For over 50 years, BlastOne has helped pipeline manufacturers implement the fastest, safest and cleanest solutions.
Good surface preparation for new construction pipelines is critical because the life expectancy is up to 40 years. Good surface preparation is vital, whatever the coating being applied. Even the toughest of coatings will fail if it does not have a good bond to the substrate it is being applied to.
With BlastOne’s experience and tailored solutions, we can dramatically cut paint downtime. Faster, more efficient equipment and systems help return your plant to operational status in less time. BlastOne ensures your corrosion control fleet is well equipped to provide consistent quality and reduce operational costs.
Pipelines need a durable and impermeable protective barrier to protect the surface from corrosion. These assets represent very high investments and if they become corroded sooner than expected, results in a loss of production and profits.
Abrasive blasting is crucial to ensure the surface is ready for proper coating application and lengthening the life cycle of the coating.
Some common issues we’ve found from working with the industry:
High maintenance costs
Pipeline projects are often in very remote locations which will require all equipment to be transported to site. The whole site process, coupled with portability of equipment can be costly along with the restricted access to maintenance and repair equipment.
Delayed project timelines
Due to the remote locations of pipelines, any small delays due to incorrect equipment causes considerable downtime. This can create long-term delays to the completion of the project.
Workflow disruptions and labor shortages
The joints of the pipelines must be welded before blasting or painting can begin. With labor shortages, project turnaround decreases.
Operator safety concerns
In-field blasting is typically around the piping joints, so the pipeline can be welded on site before it is put in the ground, particularly in the case of gas pipelines. Each weld needs blasted and coating of the weld margin usually a few inches either side of the weld. These pipelines are often buried, and if there is a pipeline failure, it is expensive to detect and repair a leak.
The Best Blasting Equipment
Due to site access restrictions often limiting the access of larger equipment, the use of portable blasting units is an ideal convenient and efficient solution. These consist of a pot, abrasive storage, compressors, air dryer, hose storage, tool box and other necessary equipment. Because of their compact “all-in-one” design, these pipeline units can be moved quickly from place to place as they are completed. They are typically mounted onto a skid for easy loading on and off truck beds.
All pipeline construction and maintenance sites require blast pots to have deadman systems. Pipeline joint blasting requires frequent movement from joint to joint, resulting in the process consisting of multiple short duration periods of blasting. This can lead to wasted abrasive and excessive time waiting for the blast pot to pressurize and depressurize. This type of work necessitates the use of pressure hold deadman systems i.e. the pressure remains held in the pot for start-up and shut-down speeding up the start and stop of blasting. The abrasive metering valves also needs to have capability for fine accurate adjustment, to minimize the abrasive usage. Start up time is greatly reduced with the TeraValve system, while providing highly accurate abrasive metering.
If blasting full lengths of pipe, the opportunity arises to take advantage of the maximum possible flow rates of abrasive. This requires large bore hoses and piping and super dry air. Efficient abrasive consumption is also important in reducing freight costs. As pipeline blasting sites are usually in remote locations, reducing freight is of high importance. By blasting more efficiently you reduce the the amount of abrasive required, and in turn the amount of abrasive that needs transporting to site.
For field joints in pipeline construction, use GMA Garnet ToughBlast to increase efficiency and reduce consumption. ToughBlast provides regular surface consistency and is typically used to achieve SP-18 standard with sweep blasting. Some contractors prefer using steel grit. While highly productive, using steel grit for pipeline blasting causes some difficulties to arise. The biggest issue is the cost of the abrasive, which results in the requirement to collect and recycle-it. The vacuum systems are very difficult to maneuver and very time consuming. Garnet’s cost effectiveness means that it can be single use only. Producing less dust than coal slag and other abrasives, Toughblast can be recycled up to 5x.
Why Use GMA ToughBlast
Use up to 30% less abrasive per joint.
30% less abrasive consumption also means 30% freight cost.
Increase blast speed per joint by up to 50%.
Coal slag is a waste product and can cause leaching of heavy metals into soil and waterways. Garnet is naturally mined product free of heavy metals.
Up to 70% less dust than slag abrasive.
Cleaner surface due to no impregnation.
Slag abrasives tend to impregnate the steel surface which can cause coating adhesion issues.
Superior feathering, cleaner joint coating.
Internal Surface Blasting
Surface preparation of large pipe or tunnel interiors is always dangerous, labor intensive and is typically preformed under tight time constraints. Robotic internal pipe technology (RIPT) blast equipment features rotating lances which are adjusted to the size of the pipe/tunnel.
Other robotic internal pipe technologies feature 3 rotating nozzles which are attached to a self-propelled trolley and move down the pipe.
Typically with metal spraying, a zinc metal spray is applied directly onto the surface. Next, an epoxy or urethane coating is applied. These are expensive coatings, but has been proven to be durable, UV Resistant and abrasion resistant.
A second option is a three coat system consisting of zinc rich primer, an epoxy build coat and then a urethane top coat. The urethane top coat maintains good gloss levels for improved self cleaning. Contaminants are less likely to stick to the surface. Additionally, there is not any chalking of the surface that typically comes from epoxy coatings.
Typical DFT without a zinc metal spray base is a total of 350-500 microns (14-20 mils). When liquid coatings are applied over metal spray (very rough finish), the top coating is normally 16 mils because the liquid coating must level out the rough finish of metal spray.
When applying hot metal spray, dedicated equipment is used. This equipment is similar to that used in a mig or oxy welding system. A wire or powder is molten with a flame or electric arc. The following intermediate and top-coats will be applied with an airless sprayer. When hot metal spray is not used, the entire coating system will be applied with an airless sprayer. Airless spraying enables the highest application rates. It also has a high transfer efficiency; this means more coating stays on the surface being coated rather than blowing away in the wind.