The SPL Process

A thorough eight step process covering cleaning, conditioning and phosphating. The cleaning process utilises varying strength alkaline silicate solutions at 50ºC to remove oil and grease followed by water rinses. Following a conditioner rinse, the shell is immersed in a bath of zinc, manganese and nickel (tri-cation) phosphate solution. Water rinses remove the excess phosphate solution and finally the shell is rinsed with demineralised water.

Next, the shell is fully immersed in a 33ºC, 55,000 litre PPG paint t a n k . Experience ensures a highly uniform paint film of between 22?m and 28 ?m with excellent bond strength is achieved as an electrical current of around 400 volts and 600 amps is passed through the shell. An Ultra Filtrate molecular resin solution rinse is then applied prior to curing.

The shell passes through a high temperature oven at 180ºC for 45 minutes. This will cross-link the polymer resin allowing the coating to become smooth and continuous. Crucially, the controlled heat drives out residual moisture from within the seams and box sections.