Postle Industries has developed a cost-saving procedure for re-application of hardbanding that promises cool tool joint internal diameters and protects the Internal Plastic Coating (IPC).
The Postle process, named CoolBanding® (patent pending), helps to protect the IPC by reducing the amount of heat introduced into the tool joint during the hardband re-application process.
During a typical hardband re-application, which generally requires a preheat of the tool joint from 300° to 450°F (150 - 230°C) depending on diameter, the temperature of the tool joint can easily reach 600° to 700°F (315 - 371°C) resulting in burned or seriously damaged IPC. If water is introduced to try to keep the plastic coating cool, the quenching effect of the water will raise the hardness of the tool joint base material directly below the hardbanding (Heat Affected Zone) to the point where it becomes brittle, and could result in catastrophic failure of the tool joint. In addition, when the tool joint is heated over 400°F (204°C) there is a high probability of burning and flaking of the IPC which can lead to clogging of the mud motor screens.
When using Coolbanding, the temperature of the tool joint never goes beyond 400°F (204°C). The Coolbanding procedure reduces the likelihood of burning and discolouring the IPC. In addition, it reduces the dependency on propane or other gases and other heating methods, and is also ideal for cold weather applications.
Welding parameters for the process differ from those necessary for typical hardbanding reapplications. The Coolbanding process requires a separate certification. While standard hardbanding equipment may be used, there are some mandatory minimum requirements regarding the equipment.
Read the article online at: https://www.oilfieldtechnology.com/drilling-and-production/06062017/new-hardbanding-reapplication-procedure-protects-internal-plastic-coating/