How much preparation is required before using GREENKOTE Thermo-Diffusion coating?
This depends on the condition of the parts received. Lubricants, oils and grease need to be removed with an alkaline cleaner in a parts washer. Heat treat scale or rust need to be removed by mechanical cleaning, usually in a blasting cabinet.

What are the part size and shape limitations?
Although large pieces can technically be coated, it becomes more of an economic question. Very large pieces limit the number of pieces that can be coated in one batch. Typically pieces 5 mm to 2000 mm (0.2” to 78”) long can be Thermal Diffusion coated. Part thickness of 0.125” or 8 gauge are good. The process provides uniform coatings to ID/OD surfaces, blind holes, threads, filets and sharp corners. Flat pieces or parts that want to nest may present a problem.

How large of a batch can be run in production?
Retorts, the metal vessels for thermal diffusion coating, can range from approximately 110 kg (250 lbs) to 6800 kg (15000 lbs).

How long is the batch time?
Usually the process temperature is held for 60 minutes, longer for special parts or thicker coatings. With a 30-minute ramp up and 30-minute cool down the typical batch time is 2 hours.

What variables need to be considered for Thermo-Diffusion coatings?
The critical variable for consideration is process temperatures. Parts need to withstand 380° C (716°F) for Zinc anti-corrosion coatings and up to 1000° C (1832° F) for specialty hard surface and high temperature corrosion coatings.