PD two-bearing housings and their covers are made of grey cast iron.
Paint, corrosion protection
PD housings are painted blue (RAL 5007) using a solvent based alkyd paint. The paint protects the housing in accordance with ISO 12944-2:1998, corrosivity category C2 (i.e.exterior atmospheres with low levels of pollution, interior atmospheres where condensation may occur). The paint is not affected by most lubricating or engine oils, cutting fluids or alkalescent washing chemicals. Housings can be repainted with most water or solvent based 1- or 2-component paints.
Unpainted surfaces are protected with a solventless rust inhibitor.