Underbody Coating

UNDER BODY COATING

Under body coating (anti rust coating) as the name suggests ,it's a coating provided to prevent rusting . Under body coating will protect the vehicle chassis from external environment (i.e muddy water stone, patholed roads,other obstacles on the road),to ensure the intergrity and safety of car. Under body coating play a very important role in the service of the vehicle. In general under body coating there are various methods.

• Manual process where the person sprays the coat by lifting the vehicle to an appropriate height. Nowadays this is performed by high speed robots that ensures a thorough coating on intricate positions.

Another process is where the automobile frame is kept in a bath of liquid coat. The liquid in made to fall in a plent of amount and than the frame is allowed to get dry and the coat gets set on the frame.

Vehicle chassis affect by external environment (left side image)

After Under Body Coating Process (Righ side image)

UNDER BODY COATING PROCESS IN AUTOMOTIVE INDUSTRY (Ref given below)

• Pretreatment: removes and cleans excess metal and forms an appropriate surface structure enabling bonding of a corrosion protection layer.

• Electrodeposition (ED) of the anti-corrosion or rust prevention layer.

• A Sealer like Poly Vinyl Chloride (PVC) is applied for anti-corrosion, elimination of water leaks, and minimization of chipping and vibrational noise.

• A Primer is then applied to promote adhesion between the surface and the basecoat; it also imparts a smoother surface for subsequent layers and has anti-chipping properties.

• Finally, the topcoats that include a basecoat and clearcoat are applied; they provide surface properties that are sought after, including color, appearance, gloss, smoothness, and weather resistance

DIFFERENT TYPE OF UNDERBODY COATING:

1. Rubberized underbody coating.

These coating are easy to apply and offer sound cushioning as well as protection from duct, moisture and dent. The coating are safe even to use on wheel wells and quarter panels and when it is dried form a soft rubbery finish that prevent further rust and moisture seep

2. Polyurethane underbody coating

This type of undercoating is a lit a bit quicker and easy to apply. This type of under coating often comes in a canister ready to preload into application gun. This type of undercoating always requires surface preparation before applying.

3. Wax or Paraffin Based underbody coating

It is cheapest and quickest option available in the market. But these coating last only for one year of duration.

4. Asphalt based underbody coating

The above mentioned undercoating is mainly used for light commercial vehicle. For vehicles such truck,bus,vancetc. Asphalt based undercoating is used for sufficient protection against rock chips and moisture. It is little bit of rubberised matrial that set up firmly and also helps in reduction in noise.

HERE ARE SOME BENEFITS OF UNDERBODY COATING

• RUST PREVENTION
  Ideally any additional underbody coating should be applied when the car is brand new and clean. Car manufacturers use thick paints and sealants for the underbody, but adding an underbody coat especially in coastal cities is useful. Salt water tends to corrode cars really badly. bad roads, flying stones and pebbles can chip off the original underbody coating and leave the metal exposed. Using an aftermarket underbody coating offer extra protection.
• SOUND INSULATION

The thicker underbody coatings used on cars also act as effective sound dampeners. They can reduce road noise and tyre noise and make the cabin seem quieter – due to the sound absorptive nature of rubberized paints.

• EASY MAINTENANCE

A uniform black underbody coating gives a car a clean look. It also makes the car easier to maintain by just hosing the underside down. You can be confident that slush build up won’t lead to rusting easily. Most underbody coats these days come with a five-year warranty, which is the lifetime of such a coating.

HERE ARE SOME OF THE DOWNSIDES TO UNDERBODY COATING:

• HIGH COST

Cost of underbody coating has come down, but is still expensive. This is because underbody coating offered by a car dealer is one way in which they make money off the customer.

• RISK OF DAMAGE DURING APPLICATION

Care must be taken while applying underbody coating. This thick rubberized paint if not applied properly, can get into moving mechanical parts and cause premature failure – such as into the U-joint or CV joints in a cars propeller shaft or drive shafts. They can also hinder smooth movement of suspension components, if applied incorrectly. And there’s also the risk of overspray on to the car’s paint finish on the lower edges of the car.

PROC OF HAVING UNDERBODY COATING:

1. Helps to Protect Against Rust:

The biggest benefit to having a car undercoating installed is that it helps to protect against rust and corrosion. The undercoating of your car can come into contact with many items that can cause it to rust or corrode. Coating it helps to prevent this from happening.

2. Helps to Extend the Life of Your Car

Rust and corrosion can shorten the lifespan of your car. The rust and corrosion can eat away at more than just the undercoating of your car. They can work their way into the metal wires in your car and any parts made from aluminum or steel. This includes your engine and the gears in your transmission. Coating the car helps to prevent this, which in turn, helps to extend the life of your car. If your car is already older or you do not plan on keeping the car for a prolonged period of time, having an undercoating installed may not be worth it to you. However, if your car is brand new and you plan on keeping the car for a long period of time, undercoating can help protect the car and maximize its lifespan.

CONS OF HAVING UNDERBODY COATING:

1. Can Be Costly if Your Car is Used

The best time to apply an undercoating to a car is when the car is new. This is because there is not yet debris, residue and corrosion on the underside of the car. If your car is used, you have to remove all of this residue before the undercoating can be applied, otherwise you are just sealing all of the gunk in. This can be costly and may not be worth it if your car is already on the downhill slide in its life.

2. Will Not Protect Against Rust Already Present

The other disadvantage to having a car undercoating installed is that it will not protect against or help with rust that is already present. If rust is already present, you will need to have it removed and the metal repaired before an undercoating can be applied. Simply spraying on the undercoating will not help once rust is present

REFERENCE:

1. “Nelson K. Akafuah , Sadegh Poozesh, Ahmad Salaimeh, Gabriela Patrick, Kevin Lawler and Kozo Saito” Evolution of the Automotive Body Coating Process—A Review - 2016
2. https://www.cartoq.com/do-you-really-need-underbody-coating-and-teflon-for-your-car/
3. http://alqasr-hojo.com/2017/08/14/the-pros-and-cons-of-having-a-car-undercoating-installed/