Underbody Coating

Under Body Coating:

• Coatings provide chemical and corrosion resistance, along with several other properties based on different product formulations.
• Coatings are applied to the underside of vehicles to protect them against factors such as corrosion, chemicals, moisture, water damage, and chipping of the underbody.
• Automotive underbody coatings also offer protection against humidity, moisture, and wet conditions that can seep through the undercarriage of a vehicle through joints or cracks in the paintwork and cause corrosion.
• Elasticity of polymers used in automotive underbody coatings allows for low noise when struck by road debris compared to that with uncoated underbody. As a result, vibrations of vehicles are dampened and kept to a minimum.

Types of Undercoating:

• Rubberized Coating: Rubberized vehicle undercoating is easy to apply and offers sound-cushioning as well as protection from dust, moisture, and dings or dents. In addition to your undercarriage, rubberized undercoating is also safe to use on wheel wells and quarter panels, and dries to a soft rubbery finish that prevents further rust, damage, or moisture seeps. The coating can be painted over and, if necessary for bodywork, can be easily removed with an undercoating removal spray
• Polyurethane Undercoating: The other option for undercoating your vehicle is to use a polyurethane-based sealant. This type of vehicle undercoating is a little bit quicker and easier to apply. Oftentimes, polyurethane undercoating will come in canisters ready to preload into an application gun. This type of sealant works by seeping into all cracks and seams, displacing salt and moisture and oozing around rusty areas to bond with and protect unoxidized metal.
• Wax or Paraffin-Based Undercoatings
  A paraffin-based undercoating will be the cheapest and quickest option available with which to protect the undercarriage of your vehicle. However, keep in mind that it will wear off quicker than other types of undercoating and will need to be stripped and reapplied at least once every year. For large trucks and heavy machinery, asphalt-based undercoating provides a bit of extra durability against rocks, chips, and moisture.
• Asphalt-based undercoating : It contains a little bit of rubberized material that sets up firmly and also helps soften noise. Used only for undercarriages.

Coating proces:

• Pre-treatment:The first step in preparing BIW for subsequent coating is the pre-treatment process. Pre-treatment consists of cleaning the body surface to remove remaining oils from the stamping process and welding residues through three primary liquid dip processes of degreasing, conditioning and phosphating.

• Electrodeposition (ED):The metal underbody and frames of automobiles are coated to prevent corrosion, whereas other areas like the roof are not rust-proofed. When not coated to prevent corrosion, the structural metals (or other materials) are primed before applying additional coatings. The ED processes are modified as per the BIW material property. This ED coating provides rust and corrosion protection.
• Rust-proof materials: Sealer/PVC
  The third step is underbody coating (UBC) and seam sealing using PVC and urethane. The sealant is applied around and inside the doors, hood, trunk, and front dash and onto the exterior and interior of metal joints and outer area of the back wheel well.
• Primer:
  The fourth coating step is the application of a primer surface or simply primer. It can be water-borne, solventborne or a powder. These primers are used to improve adhesion between the E-coat and topcoat, provide chipping protection, enhance paint appearance and also be environmentally compatible with emission regulations.
• Top-coat:
  The final step in the body coating process is to apply the topcoat, which consists of two layers-the basecoat and clear coat. The basecoat contains the primary colouring pigment and the clear coat provides a protective coating against environmental effects, corrosion, and UV light degradation promotes unmatched colour retention and provides a smooth unblemished even finish.

ADVANTAGES:

• protection against rust and corrosion
• vehicles in warmerclimates gain protection as debris is repelled and kept away from eating at the vehicle.
• minimizes the sound from underneath the car
• It insulates the interior of the car from the extreme temperature from beneath the vehicles

DISADVANTAGES:

• It must be reapplied every 3 to 5 years for the best results .
• It adds weight to the vehicle.