Underbody Coating

Underbody Coating

It is a preliminary stage of Painting where the body is dipped completely into the paint tub and rotated in such a way that it gets fully coated over the entire body. It is more like Painting. The main purpose this operation is to protect the Body from corrosion which generates through moisture, water, and wet environment. The automotive coating process consists of at least five layers of protective and decorative paint. However, the underbody only receives the first two layers and remaining three layers are needed to give it elegant looks.

Some images depicts normal Coating in Automotive industry.

Why is a car underbody coating needed?

If you have ever travelled in an old car down a gravel road you have heard the thunderous sound of hundreds of tiny pieces of rock being hurled at the underside of a vehicle. Not only is it deafening, but it is also damaging. The car underbody coating provides protection against:

• Moisture
  By covering cracks in the paintwork or joints in the undercarriage of a vehicle, moisture, or water from humid or wet environments is prevented from creeping into the underbody and causing corrosion.
• Corrosion. Stone chip damage may expose the metal itself, leading inevitably to corrosion.
• Stone chip damage
  A car underbody coating provides a durable elastic over the underbody and wheel arches which protects the substrate from stones, gravel, salt, and other debris which is thrown up by the road.

Different types of underbody paint depending on the environment

Most commonly these coatings are one of the three types

1.Resin-based:
Polyurethanes and rubber coating are popular because their elastomeric properties provide long-term stone chip damage and corrosion protection as well as sound deadening effects.

2.Wax-based:
An excellent anti rust coating suitable for all substrates. The wax is applied soft and cures hard, either by brush or spray, and can be layered thickly. It cannot be top coated.

3.Bitumen-based:
These underbody paint systems provide hard-wearing protection against stone chip damage and corrosion. They also have sound-deadening properties. Suitable across many substrates but cannot be painted over. Can be applied by brush or spray, high build, and good for very tough conditions such as off-road (like in the South Asian Countries).