What are the steps of car sheet metal? What is the operation process of automobile sheet metal?

Generally speaking, the basic equipment of sheet metal process includes shearing machine, CNC punching machine, laser, plasma, water jet cutting machine, bending machine, drilling machine and various auxiliary equipment such as: uncoiler, leveling machine, deburring machine, spot welding machine, etc.

Generally, the four most important steps of the sheet metal process are shearing, punching, folding, welding, surface treatment, etc.

Sheet metal is sometimes used as a wrench, the word ** in English platemetal, generally some metal sheet through manual or die stamping to produce plastic deformation, forming the desired shape and size, and can be further welded or a small amount of mechanical processing to form more complex parts, such as the commonly used chimney in the family, iron furnace, and car shell are sheet metal parts.

Sheet metal processing is called sheet metal processing. For example, the use of plates to make chimneys, iron drums, oil tanks, ventilation pipes, elbow heads, round places, funnel shapes, etc., the main processes are shearing, bending buckles, bending forming, welding, riveting, etc., which require certain geometric knowledge.

Sheet metal parts are sheet metal fittings, that is, parts that can be processed by stamping, bending, stretching and other means, and a general definition is -

Parts with constant thickness during machining. The corresponding are castings, forgings, machining parts, etc., for example, the iron shell on the outside of the car is sheet metal parts, and some cabinets made of stainless steel are also sheet metal parts.

Modern sheet metal processes include: filament power winding, laser cutting, heavy machining, metal bonding, metal drawing, plasma cutting, precision welding, roll forming, sheet metal bending forming, die forging, water jet cutting, precision welding, etc.

The surface treatment of sheet metal parts is also a very important part of the sheet metal processing process, because it has the effect of preventing rust of parts and beautifying the appearance of products. The role of surface pretreatment of sheet metal parts is mainly to remove grease, oxide scale, rust, etc., which prepares for surface post-treatment, and post-treatment is mainly spray (bake) paint, spray plastic and anti-rust coating.

In general, there are three steps, the first of which is also relatively basic and critical.

The second step is some of the usual steps, and the third step is more important.

1. Dismantling of the whole car: remove all the sheet metal parts that may be involved or the parts that are painted for painting;

2. Body repair: replace, stretch, weld, and repair injuries such as iron plate dents, beam bending, and dimensional displacement caused by impact or overturning;

3. Sheet metal repair: all damaged parts should be repaired.

What is the automotive sheet metal workflow? Understand the process well, and it is not easy to be pitted when repairing the car!

1) Damage confirmation. After the damaged area is cleaned, the extent of the damage is confirmed, and a repair method is established. (2) Sheet metal disassembly.

The sheet metal parts of the damaged parts of the collision vehicle are removed from the original body by cutting or other means. (3) Remove the old paint film. The original paint on the damaged part is sanded until the iron plate layer is exposed.

4) Sheet metal parts are leveled. According to the degree of damage to the sheet metal parts, the corresponding sheet metal tools are used to flatten the depression parts. After the leveling operation, the surface of the sheet metal parts should be finely adjusted for flatness.

In the process of repairing a collision vehicle, the operation process of sheet metal and painting is very complex, and the maintenance skills and experience requirements of maintenance personnel are also very high. In order to allow car owners to understand the operation process of sheet metal and painting, we will take the operation specifications formulated by sheet metal and painting operators in the sheet metal painting competition as an example to briefly introduce the operation process of sheet metal and painting.

If the collision of the car body is serious and the frame is injured, it is necessary to correct the whole vehicle structure on the frame straightening machine, and the operation will be more difficult.

Painting operation process:

1) Damage confirmation. After cleaning the damaged area, the extent and extent of the damage are confirmed, and a repair method can be established.

2) Polishing the feathered edges. A buffered slope is sanded at the connection between the damaged part and the surrounding paint film, so that the newly sprayed paint surface can be better connected with the original paint surface.

3) Apply an epoxy primer. Clean and degreased the damaged surface again, apply epoxy primer and dry it for anti-rust treatment.

4) Scrape putty. After the damaged parts of the sheet metal coated with epoxy primer are slightly sanded and cleaned and degreased, they are scraped and coated with putty, which is often referred to as putty. After the putty is dried, it is sanded, and the stamping line is confirmed.

5) Spray primer. After sanding, the putty is cleaned and degreased, the primer is sprayed, and the baking is dried. When spraying primer, pay attention to the parts that do not need to be sprayed in reverse.

6) Primer in sanding. The primer is sanded to the same height as the original paint surface to confirm the flatness.

7) Paint mixing. Although the original paint is generally available in the authorized service stores, the color of the topcoat is different from the original paint after the vehicle has been used for a long time, so it is necessary for the painter to manually adjust the paint.

8) Spray the topcoat. Add the adjusted topcoat to the spray gun can, adjust the air pressure, paint output and spray width of the spray gun, and start to spray evenly on the sheet metal parts. Different topcoats have different processes when spraying.

9) Polishing. Remedy and brighten defective topcoats.

Photo by Brother Choosing a Car) @2019

1: Sheet metal correction.

After we determine the plan, the first step is actually correction, and our maintenance personnel will use the corresponding tools and techniques to repair the deformed parts of our car according to the deformed Chengdu of our car. There are many ways to make sheet metal, including cutting, stretching and grinding, etc., in short, they will use various methods to restore our car to the maximum extent.

2: Finalization. When our car is corrected, it will definitely be different from other parts, because the vehicle has received damage after all.

At this time, the maintenance personnel need to shape the vehicle, apply putty to shape our body, and make the damaged parts as much as possible as before we were damaged. This operation is basically the same as our usual wall scraping putty, which requires patience and carefulness, which is a great test of the skills of maintenance personnel.

3: Spray paint. The third step is to spray paint, the process of painting is more troublesome, we must know that this work must be in a dust-free environment.

The steps must also be in place, showing the primer, followed by priming during the spraying process, followed by primer in sanding, dispelling hail and finally topcoat. In short, the process of sailing is very troublesome, but it must not be careless and sloppy, and in the end, it must not forget to dry the paint.

4: Paint finish.

The last step is to deal with the paint, if you want to make the car really not see the flaws, it is better to refine, as long as the problem is not very big, there will be no obvious difference, the whole process is relatively fine, this step seems simple, but it is essential. In fact, it is the finishing work, but it requires patient inspection, careful polishing, and grinding away the imperfections.

Sheet metal painting is a kind of automobile repair technology, which is to repair the deformed part of the metal shell of the car. For example, if the shell of the car body is hit with a crater, it can be restored to its original state by sheet metal, and then the deformed metal surface of the car can be restored to its original brightness by spraying special paint. The basic process of automotive sheet metal painting is usually divided into four steps: sheet metal correction, sheet metal correction is for automotive sheet metal painting.

First, the preliminary plastic surgery work.

As we all know, how can a distorted and deformed body bring out the brilliance of paint? To put it bluntly, it is to restore the deformed parts, including the body shell, chassis girders, etc. At present, sheet metal correction has developed from the original "smashing welding and repair" to the secondary manufacturing assembly of the body.

Maintenance personnel should not only understand the technical parameters and dimensions of the body, but also master the material characteristics of the body, the characteristics of the force to transmit the deformation trend and stress point of the body and the production process of the body. Such as welding process and so on. On the basis of mastering these knowledge, maintenance personnel should also use advanced measuring tools, through accurate three-dimensional measurement of the body, to judge the direct and indirect damage and deformation of the body, develop a complete body repair plan, with the correct body repair plan, the key points of the body are restored to the original position.

Second, scraping ash shaping.

There are some irreparable defects after the car body is corrected by sheet metal, even if it is to replace the new parts will have imperfections, in order to achieve more perfect precision, it is necessary to use the craft technique of sculpture to make up for the defects, the car is damaged after deformation and other residual reasons, its flatness, wheel angle and line, each part needs to be filled with scraping ash to reshape out. Scraping = restoring the body skin = mold product = mold processing program. Any body skin of the car is stamped by the mold, and the repair of the body skin is the same as the repair of the mold, so we scrape the ash and shape the process to be coherent with the mold processing.

Many painters who have been working for many years will sigh a sentence "It is easy to spray a car, but it is difficult to make a piece of ash, and it is difficult to grind a lump of ash in ten years".

Hello, car sheet metal repair is a complete repair of faulty and damaged car bodies.

One: car body assembly This is a common accessory name, including: body sheet metal parts of the car glass, the whole car lamps, the whole car, the interior and exterior decoration parts and handles, seats and accessories, lock mechanism, window sealing and lifting mechanism, door and front and rear sail cover of the sum of the connection activity mechanism.

In other words, when your car has problems such as broken glass, door lock failure, damaged trim, etc., remember that you need to find the car sheet metal and not other types of work!

2: The sheet metal work process is explained in detail and the whole car is disassembled, which may be involved, or all the sheet metal parts of the painting work are removed. The car body repair will be caused by impact or overturning caused by the iron plate dentation, beam bending, dimensional displacement and other injuries to replace, stretch, weld, etc.

Sheet metal repair, all damaged sheet metal parts should be repaired for bonding, welding and other appearance and size restoration.

Sheet metal parts are strictly repaired, and the repaired sheet metal such as doors and lights and non-sheet metal parts such as displaced machinery and electrical appliances are reset, which requires superb skills and unremitting patience to achieve accurate installation and beauty.

The whole car is installed, all sheet metal parts are installed and fixed after painting, and all movable sheet metal parts are tested.

The practice of automobile sheet metal is as follows:

1. First of all, all the damaged parts should be cleaned up, and the workload and repair method should be determined according to the size of the damaged area.

2. Sand all the paint and putty on the damaged part of the vehicle.

3. Straighten and straighten all the iron plates in the damaged position for finishing. If there is an unevenness, it can be smoothed with putty.

4. By using sandpaper to polish the place where the ash and putty are filled, the polishing must be careful.

5. After all the grinding is smooth and smooth, you can spray paint after drying, and you need to bake paint after spraying.

Material requirements for sheet metal

1. The sheet metal material must have good plasticity. It is necessary to have the ability to produce permanent deformation without being destroyed under the action of external forces. For cold work parts, it is necessary to have good cold plasticity, such as stamping parts of automobile parts; For hot work parts, it is necessary to have good thermoplasticity, such as hot forgings, spring steel plates, hot rivets, etc.

2. Good weldability. Many automotive sheet metal parts are welded together by electric welding, oxygen welding, arc welding or gas shielded welding, so sheet metal parts must have good welding performance. This is especially important in the repair of automobiles, where materials with good weldability have high welding strength and low cracking tendency.

3. Good chemical stability. Most of the car panels work in the open air, often in contact with water and steam, especially like mufflers, often working at higher temperatures and corrosive gases. This requires that sheet metal parts must have good chemical stability, which not only requires corrosion resistance and strong rust resistance at room temperature, but also requires that they are not corroded and deformed under high temperature or sun exposure.