Car white body paint, a total of a few steps?

In many people's eyes, a car is the most important appearance, beautiful shape, bright colors of the car can always get more favor. If the car than a man, car paint is clothes. BIW Welding line, after coating workshop put on "clothes", it can be said, is a white body painting workshop "locker room".

         As the stamping or welding workshop, one of the most important painting workshop is in the process of automobile production, but unlike other workshop, painting workshop rarely open, even in the new factory media open day, can open paint shop car prices also scanty. This is to paint the body covered with a veil of mystery, in this to the body "wear clothes" in the mystery of the workshop, which we do not know the secret?
 
A car wearing a few clothes?
        When it comes to painting, had to start the car paint clothes “ ” speaking, like people, car clothes is lined by the coat etc., considering the cost and the level of technology, different manufacturers to car clothes are slightly different, but the process of the mainstream car are more or less.


        Here we pick up a steak, the car in the end what clothes to wear: after the treatment of the white body (figure in the base material) after the formation of phosphating phosphating film, which is the body and the most tight clothes. Outside the phosphating film is an electrophoretic primer, which requires special techniques to wear the coat.——Electrophoresis.After electrophoresis in the coating, coated outside is the body of the coat——Finish.Finish is divided into paints and varnishes, we see the color of the body is the color of paint. Some car coat is too precious (luxury car paint, paint so expensive) in the outside with a layer of transparent coat——Varnish.

        The car paint is very thin, is a micron level. What is the concept of micron? 1000 microns is a millimeter. The phosphating film a few microns, paints and varnishes only tens of microns, which put forward higher requirements on the body surface of — — white body and coating surface finish, any small protrusions will affect the appearance of the body. Outsiders into the painting environment is easy to destroy clean, so the painting workshop rarely open to the outside world.
 
How do I wear micron grade clothes?
        Painting workshop has been known for the mysterious, but the process of understanding the car to wear clothes, painting is no longer mysterious. The process of wearing clothes is the body painting process. Although the clothes color difference is very big, but the dressing process is similar.

        Car painting is more complex, white body after the formation of phosphating film before treatment, and then through the electrophoresis to form a primer, after the coating to be carried out, the final spray paint and varnish, body painting finish.
 
        The huge painting workshop, a painting line connected between each process, every step has not stepped to the order after. Painting most processes are carried out in a closed room, which gives the process to provide a suitable environment, but also to protect the painting staff.
 
Pre-treatment——Body wash
        In the welding workshop from BIW eighteen Wu Yi is not “smooth”——Oil, the welding welding slag, dust and so on, more or less on the body surface, the pretreatment process is to put these stains for processing, so that the body was required. Obviously, the process is very complex. (as shown in the figure below)

        After entering the painting workshop, the body must first go through hot water to wash, remove the surface of the larger contaminants, while hot water also soften the grease. After washing is going to enter the process of fat (fat is oil), skim the body after the white body to be washed again in order to carry out the surface adjustment. Water is divided into two categories: one category is immersion, as the name implies, completely immersed in water washing; the other is spray washing, washing water cannons at special sites. Mix the actual water washing process in two ways.

       
        The surface adjustment after entering the phosphating process of phosphating, the purpose is to make the form a protective layer to increase film adhesion and corrosion resistance and moisture resistance of the body surface, and the phosphating process is very simple: the body is placed in the phosphate solution, appropriate temperature, the surface can be generated in a metal salt film, that is before we mentioned the phosphating film. After the formation of the phosphating film and then after the passivation, and finally washed, before the treatment is completed. At this time the white body also reached the electrophoresis requirements.
 
electrophoresis——Special dressing method
       The purpose of pre treatment is to give the body paint primer, primer can make the body get rust, shock resistance, corrosion resistance and other properties, the process is to complete the painting process is electrophoresis. In 60s of last century, Ford was the first to use this technology.


        After electrophoresis, the primer layer uniform integrity, and to the body structure of the coating chamber, cracks and other hidden inside, very helpful for preservation, is now the most mature coating technology.
 

Middle coating preparation——Sealing process and underbody coatings
       Body in white welding line in the assembly, each panel joints prone to sealing problems, car floor in the process of moving to bear stone soil impact, paint sensitive, rusting.
 
        In order to improve the sealing and rust resistance of the body, the bonding surface of the body panel is required to be coated with a sealing material, and the automobile bottom plate needs to be processed by coating. Now car seal and underbody coating using PVC series material, so this line is also known as the PVC painting line.

        In the PVC coating process, but also mount sound isolation and vibration damping materials to enhance the ride comfort in the engine compartment on the bottom surface of the body and other parts, by reducing pavement contact and body vibration of the engine, the noise and has a thermal insulation function.
 

floating coat——Connecting role
        Coating is one of the most important automobile coating process, the coating plays a connecting role: the lower is the electrophoresis primer, the upper body paint, so between the coating primer and finish coating is protection and decoration, and help fill the pit under the primer, then meet the arrival of surface paint.

     
        Why the need for the coating process? Mainly because of the electrophoresis primer is too fragile, ultraviolet finish after irradiation, easy primer powder, will cause the rust from the primer within a short period of time. And paint directly onto the primer layer and poor adhesion. So in the process of painting, between the primer coating and finish coating intermediate coating, in order to improve the durability of the adhesion of the coating and coating, so that the car to wear the right coat.

Finish——Car coat
         The car outside the paint and varnish called paint, paint and varnish effects are also different. Color paint to the car brought colorful clothes, showing the car's personalized, while protecting the coating and electrophoresis primer. The varnish layer has the function of resisting pollution, acid rain, anti ultraviolet ray and so on. It can protect the color paint better, and it is also the clothes we can touch.

        Finish different enterprises have different colors, automobile paint can be divided into color and metallic color (metallic color and pearl color) two categories.
 
Post treatment——Finishing process
        Paint spraying after drying, drying, cooling into the final quality inspection process.“clothes”After passing the need for postprocessing: polishing wax polishing can make the topcoat with gentle and stable luster, make surface more smooth, this is a means of improving decorative coating. In addition, in the course of vehicle transportation, the protection of the car's appearance can play a role in storage, to prevent the erosion of high temperature.

       
         Automotive coating in the four most mysterious process. And the clothes, also need painting by process, generally by the pretreatment line, car body coating line typical electrophoresis line, coating line, bottom sealing coating line, finish line and postprocessing lines, six lines, six lines connected together into a group of painting production line this is the complete process of automobile, dress, along with the development of new coating technology, automotive clothing has become increasingly rich, the future will also appear more beautiful car“clothes”。