How To Apply Powercrete J
The "Standard Kit" contains an installation guide, SDS and a 2 part epoxy coating (Powercrete J) in premeasured kits. Part A (the large container) is the base and Part B (smaller container) is the curing agent.
Insure that surfaces are clean of grease, oils, salts and other contaminents. If necessary, use Acetone, MEK or other suitable solvent. Perform cleaning when pipe is 3C above the dew point.
Blast clean surfaces to be coated with Powercrete J to a near white SIS Sa 2 1/2 or white SSPC-SP 5 using particle blasting. Sweep blast adjacent FBE or CTE coating 50mm to either side of the cutback (the bare steel area).
A 70 to 80 micron (2.7 to 3 mil) surface profile is ideal. Burnishing or polishing must be avoided. Surface preparation can be controlled using surface profile tape. Dry surface and insure ideal surface preparation.
While not always necessary when applying Powercrete J, preheating can be useful just prior to application: A: To eliminate moisture, preheat the cutback area to approximately 40C and B: to accelerate curing, preheat the cutback area to approximately 90C.
Warm parts A & B of the Powercrete J to 20C and mix by pouring all of part B into part A. Thoroughly scrape container and lid of B. Slowly begin mixing to avoid introducing air into the mixture.
Use a mixing speed when mixing the Powercrete J that uniformly blends the 2 parts, but does not create a vortex in the mixture or spillage.
Reconfirm that the temperature is above 10C and 3C above the dew point. Then slowly pour the Powercrete J (mixed) onto the pipe.
Use trowels, brush or roller to apply required minimum thickness of coating to the field joint. Cover at least 50mm of the adjacent mainline coating.
Use a wet film gauge to measure that the desired thickness of Powercrete J has been achieved. Double check around the weld to insure minimum desired thickness.
The curing rate for the Powercrete J will vary according to pipe and ambient application temperature. Refer to a curing chart for Powercrete J to determine when to perform a Shore D check.
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