Effect of process control on product quality in steel drum production process

For the product structure alone, the steel drum is a relatively simple product, just like people often say "not a big three-piece can." But in fact, to produce a qualified steel drum, it has to go through nearly 30 processes to complete. The degree of process control in each process is different, and the impact on the quality of the finished steel drum is also different. In particular, the process control of key processes is extremely important. At present, there are two types of steel drums, which are divided into openings and seals. The degree of manufacture differs due to their different capacities and different conditions of use. When re-manufacturing steel drums for oil loading, the control requirements for each production process are higher. The following is a discussion on the process control points in the production process of 200 liter oil-packed steel drums.

First, the quality control of blank blanking, forming and other processes

The blank blanking and forming process includes: appearance quality inspection of the barrel body and the bottom of the barrel and the cover material; the cutting and cutting of the barrel body; the barrel body is rounded; the bottom cover of the barrel is cut and cut; the bottom of the barrel and the cover are pre-rolled Glue; the barrel mouth on the barrel cover is punched and riveted, and the work process is checked. In the above process, the main quality control points are:

1. Inspection of the appearance quality of the barrel body and the bottom of the barrel and the cover material; that is, the necessary inspection and record of the material grade, specification size, surface protection and complete condition of the barrel sheet after unwinding or unpacking, such as If it is found that it does not conform to the relevant quality parameters or there are serious corrosion and defects, it should promptly respond to the inspection department and dispose of it as required. If rust and defects are found during the cutting process of the shearing board, they should be classified and stored and marked. After the batch task is completed, report to the competent leader to decide to take appropriate measures before transferring to the next process. It is worth noting that If the rough and defective rough materials are mixed into the next process and are not found, the quality of the product will be greatly affected.

2. During the stamping and forming process of the bottom of the barrel, it is necessary to observe whether there is tearing or wrinkling after the bottom of the barrel and the stamping and forming. It is necessary to timely check whether the size of the bottom of the barrel and the height of the lid are controlled within the process size range] The existence of cracking will endanger the strength of the steel drum; when the bottom of the bucket and the edge of the lid are wrinkled, the curling resistance will increase and the wear of the crimping machine will be accelerated; when the bottom of the bucket and the cover exceed the process requirements, the volume of the steel drum will be affected. The quality of the side.

3. When spraying the bottom of the barrel and the pre-rolling of the cover, first check the quality of the sealant, that is, whether there is deterioration or precipitation, etc. Secondly, it is necessary to control the uniformity and satisfaction after the glue is applied, and the sealant is deteriorated, precipitated, etc. In the case of phenomenon, the elasticity and shrinkage of the rubber will change, which will also affect the sealing of the steel drum after crimping; the unevenness or insufficient glue will also affect the quality of the steel barrel.

Second, the quality control of the steel barrel barrel spot welding and seam welding process

In the past, the spot welding and seam welding process of the domestic steel drum body was backward due to the design of the control circuit of the equipment itself, which made the spot welding and seam welding operations of the steel barrel body difficult, so it was listed as one of the key control processes. At present, with the transformation of foreign advanced automatic welding machines, the artificial control has been replaced by computer programs to a large extent, and the spot welding and seam welding operations of steel drums tend to be stabilized. In the actual barrel spot welding and seam welding operations, according to the material composition, thickness dimension and overlap width of the plate, the welding parameters are correctly selected and adjusted, and the spot welding and seam welding operations will soon be normalized, but Note that the amount of overlap in the spot welding process must be controlled by the grid, otherwise it will have a great impact on the quality of seam welding.

Third, the quality control of the expansion process of the steel barrel, the flanging, and the sealing and forming process

It is relatively easy to control the quality of the expansion and burring process of the steel drum. As long as the forming size of the forming mold is designed and manufactured to meet the process requirements, and the wear resistance of the molded part of the mold is high, the process size can be kept compared. stable. It is worth noting that the size of the flange and the angle of the flange have a certain influence on the quality of the bead of the steel drum.

According to the relevant materials and many years of work experience, the steel barrel capping process is a straightforward and difficult to control process, because it has suitable adjustment factors in addition to the moving parts of the equipment itself, the curling wheel The size of the groove, the shape and size of the cap, and the material composition mentioned in the above process, the size of the barrel bottom, the stamping of the lid, the bottom of the barrel, the glue control after the pre-rolling of the lid, the barrel spot welding, the seam welder The order control, barrel size and angle of the barrel have a close correlation with the quality of the barrel.

1. The adjustment of the moving parts of the equipment itself mainly includes the distance between the two caps and the working distance between the curling wheels. If the distance between the two caps is too large or too small, the quality of the beading will be affected. If the distance is too large, the amount of curling may be insufficient. If the distance is too small, the amount of curling may be excessive or the roll may not be realized. The working distance between the curling wheels is not suitable, and the curling may not be realized, but these phenomena do not occur under the condition that the equipment is normally not moved after being debugged normally.

2. Whether the design of the groove size of the crimping wheel is reasonable or not is the basis of the quality of the crimping. If the hemming size distribution of each set of hemming wheels must be reasonable, the curve continuity is good, and the shape size of each heel wheel is consistent with the volume of the hemming layer. Otherwise, the curling effect will be Defects such as false or "cutting" and "double eyelid" may occur, especially when the bottom of the barrel, the material of the cover and the material of the barrel are changed, in addition to the necessary theoretical calculations, reliability experiments should be carried out as much as possible. Avoid the substitution behavior of similar sizes to ensure the quality of the steel barrel.

3. Whether the shape and size of the top cover of the cover is reasonable is also one of the important factors affecting the quality of the curl. The main factors are the size and angle of the cap. If the outer diameter is too large or too small, the shape of the bead will be irregular. The angular size affects the normal transmission of the curling force, thus affecting the quality of the curl.

4. In the case where the carbon content of the material composition is too high, the forming of the hemming is difficult due to the high resistance of the material itself, and the wear of the curling wheel is accelerated, thereby affecting the stability of the curling quality. At present, most of the barrel manufacturers use the barrel sheets produced by the former Soviet Union in the course of use, which causes great difficulties for the high-level drop test.

5, the bottom of the barrel, the stamping dimensions of the cover, the stretch height and the outer width is too large or too small, which will cause excess or insufficient material when the crimping is performed and the curling level is disordered.

6. The purpose of spraying the bottom of the barrel and the pre-rolling of the cover is to improve the sealing performance of the steel drum and prevent the liquid in the barrel from leaking outward. When the amount of glue is too much, the number of layers of the curl is affected. When the amount of glue is too small, the sealing effect is not achieved (especially when the number of layers of the curl is insufficient). The sealant used for the crimping of steel drums should have better elasticity and higher solid content. Otherwise, the sealant after the steel drum is rolled and dried will have a large shrinkage, which will form a virtual volume phenomenon, thus affecting the steel drum. Sealing effect. Sometimes in order to save trouble, the material thickness specification (do not change the sealing wheel) to supplement the curling wheel groove volume to achieve the effect of the sealing glue is dangerous, will undoubtedly leave an immeasurable quality hazard.

7. The effect of spot welding and seam welding on the sealing and the quality of the seam of the barrel is interrelated, that is, the welding strength of the barrel spot welding is insufficient, which affects the quality of the barrel seam; When burning, there will be leakage at the spot weld after seam welding; the control of the joint welding of the barrel body has an effect on the seam welding operation of the barrel. If it cannot be corrected in time, it will produce a side lock reaction to the curling effect. . After the transformation of the domestic seam welding machine, the welding thickness of the welded joints (3.5-4mm) is close to the thickness of the sheet, and the quality of the curling is relatively stable. When the difference is large, it is unstable, especially the mechanical rotating cover curling. Machine, all kinds of phenomena reflect more prominent.

8. Control of the quality of each conversion process in the production process of steel drums.

The so-called conversion process mainly refers to the transformation between the barrel and the bottom of the barrel and the process of the barrel. In the process of mechanical rolling, turning and manpower handling, there will be deformation damage caused by the collision of the steel barrel material, for large formal enterprise customers. It is very difficult to pass the acceptance. Therefore, many barrel-making enterprises use the hanging conveying method to avoid the occurrence of deformation and damage during the process.

Fourth, the quality control of the surface spraying process of steel drum

With the development of the market economy, the user's surface quality requirements for steel drums have also increased step by step, not only the variety of colors, but also the requirements for brightness, clarity, coverage and uniformity, so the quality of the surface coating process of steel drums Control will be strengthened. The spraying process on the surface of the steel drum is mainly composed of the degreasing and phosphating and drying of the barrel and the bottom of the barrel, the barrel and the bottom of the barrel, the surface of the barrel and the drying and marking printing.

1. The purpose of degreasing and phosphating of the barrel body and the bottom cover of the bucket is to prepare for surface spraying. Therefore, the degreasing effect and the phosphating effect will directly affect the adhesion of the paint film on the surface of the steel drum, and the degreasing effect and the phosphating effect are not only the sampling total. In addition to the acidity or total alkalinity index control, it is also necessary to control the temperature of the degreasing and phosphating solution after the tank is arranged, and the operation procedure should be strictly followed. Under normal circumstances, the method of heating is better than the effect of using normal temperature, especially under the conditions of low temperature in northern China. Although heating has the cost of heat energy, it is easy to control, while the temperature of the room temperature treatment liquid is relatively high, and the control is difficult. In addition, according to the use of degreasing agents by various barrel manufacturers, the phosphating solution is different. It is better to stabilize a degreasing agent and a phosphating solution to avoid adverse effects on the surface quality of the steel drum by different chemical reactions.

2. The quality of the paint itself used for spraying is more direct on the surface quality of the steel drum. The gloss, adhesion and weather resistance of the paint film are all important performances after spraying the surface of the steel drum. Due to the market competition factors, the stability of paint quality is worth paying attention to by the barrel manufacturers.

3, the process control in the spraying operation should be said to be easy to adjust through the spray gun: First, control the thickness of the paint film; second, control coverage and uniformity, as far as possible to avoid leakage and sag phenomenon.

4. The barrel and the bottom of the barrel and the drying operation of the surface of the barrel are sprayed according to the drying temperature requirements of different paints in strict accordance with the corresponding technical procedures.

5. At present, there are still a considerable number of barrel manufacturers still using the lower drive rotation to spray the surface of the steel drum. This spray method has two defects: First, the bottom barrel side cannot guarantee the coverage of the spray due to the rotation of the barrel rotation. Charge (only take the subsequent manual refilling); Second, due to the accumulation of excess paint sag caused by the failure of the transmission member to affect the normal operation of the spraying work. Many barrel manufacturers use the upper drive rotary spray to avoid the above problems.

6. The spraying form of the two-color barrel has begun to spread. The quality of the spraying depends mainly on the matching of the paint quality and the nozzle specifications in the spraying operation and the occlusion adjustment of the sprayed common cutting surface. In order to ensure better spray quality, the spray operator is required to have high technical quality and operational skills to achieve quality control of the two-color barrel spray.

Through the above analysis, the capping and surface spraying process of the steel drum is undoubtedly the key to affect the quality of the 200-liter oil-packed steel drum product, so it is important to control.

The above analysis is due to the different production conditions of each barrel manufacturer, and rarely involves specific data description. It is mainly explained in terms of ideas for reference by peers.