Analysis of Status Quo of Exported Packaging Steel Drums
There are many types of steel drums exported and packaged in China. Most of the specifications are between 15 and 200 liters, of which two are more common, namely full-open and closed drums. Fully-open barrels are sealed with large uncovers and hoops to hold solids and semi-solids; closed barrels are used for holding grease and liquids.
As an export product package, the most used is of course 200 litres of steel drums, and foreign goods are often called 53 gallon drums. In the past ten years, leaks occurred when grease and other liquid materials were used. It is understood that, despite the continuous development of the technology and equipment for barrel making in recent years, the overall quality has not improved much. The current domestic 200-liter steel drums that can truly pass the drop test without leakage are few. Therefore, the solution to the leakage problem of export steel drums has always been listed as a key project for export containers. The investigation found that the locations and proportions of leakage of steel drums were roughly as follows: 10% at the barrel mouth barrel cover; 5% at the barrel body weld seam; 85% at the bead and weld triangle area, with the most in the triangle area.
To solve the problem of leakage, we should mainly start from the following aspects:
The use of an advanced seam welder reduces the seam width and thickness of seam seams, thereby greatly reducing seam leakage and seam leakage.
At present, most of the barrel manufacturers in China use steel barrel seam welders or semi-automated domestic machines, and seam welding is mostly about 10 mm. In the lap welding area, the thickness of the material is approximately twice that of the plate. This area is thicker than the other places when crimped. Therefore, gaps that cannot be compacted often appear at the transition from thick to thin, and leakage occurs. It will happen. In order to solve this problem, some barrel makers have successively adopted a variety of improvements, and some progress has been made. For example, the seam welding machine of Tianjin Jingdashao Company is improved on the original semi-automatic seam welding machine. It can not only improve the speed of seam welding, but also make the edge smaller, and the thickness of the overlap is thin; After the welding, the laps are rolled to make the double hem thin. The most advanced is the automatic seam welding machine. The welding lap width is only 2 to 4 mm, and the welding quality can be fully guaranteed. At present, the more advanced foreign technology is the use of laser welding technology, can achieve the welding of steel, its performance is more excellent.
Improve the curling process so that the curl can be effectively reached up to seven layers and compacted.
Ten years ago, the barrels and barrels of steel barrels in China all used rectangular five-layer crimping. In recent years, foreign seven-layer circular crimping technology has gradually gained popularity in China. As a result, the problem of seepage leakage has been greatly reduced. However, the quality is never-ending. Today, the problem of seepage leakage has become the key to seriously affecting the development of steel drums. From a technical point of view, the rim leak has the following aspects:
(1) The curling level is not enough. This situation is more common, because in the country began to engage in circular curling situation, there are many manufacturers do not really master this technology, just to meet the requirements of users and change the curling roller groove after the production, This kind of round curl is indeed a round curl from the appearance, but the true intrinsic quality is not guaranteed. The most obvious difference is that the number of curled layers does not reach seven layers at all, and there are only five layers. Therefore, the leaking of the crimp is inevitable. To solve this problem, it must be produced in accordance with the correct process of round curling, which of course is to invest, at least to change the size of the bottom of the bottom of the barrel, so that the edge of the curling material is sufficient; more to buy the bottom of the barrel The pre-rolling glue-dispensing machine, before the crimping, seals the edge of the bottom top into a groove type and fills in the sealant; the width dimension of the barrel flanging also needs to be increased accordingly. Only in this way can the seven-layer crimp be guaranteed.
(2) The level of crimping is not tight. Although some steel drums have seven layers of crimped layers, they are not compact. Because of the gaps, leakage has become a normal thing. The reason for this is mainly due to incorrect roll groove profile or insufficient roller compaction force. Roller groove type is the most critical technology in the crimping technology. Generally, only a few manufacturers have mastered it. Some manufacturers have not yet mastered it. The quality is good or bad, and some have yet to be further discussed. Because each manufacturer's process parameters and process methods and equipment are not the same, so the roller groove and other parameters are also different, but as long as mastered the design essentials can be random strain.
(3) Uneven crimp size. Some manufacturers of steel drums due to the impact of process quality, resulting in uneven curling size, so there are gaps in some places. For example, the size of the barrel flange is not the same as the width of the barrel, the thickness of seam welding is too thick, and the thickness of raw materials is not uniform. All of these factors can cause gaps in the curling and must be given adequate attention.
Sealants for preventing leakage shall be subject to strict inspection. Unqualified rubber shall not be used and shall be produced strictly according to the process. Wet plastic shall not be involved.
In the drum seam sealing operation, a sealant must be sprayed to fill the gap in the material in the crimp. However, some sealants are of poor quality, some have too few solidifying components, and the gaps appear after the glue is dry. Some sealants are not resistant to high temperatures. When the steel drums are painted into the drying oven and dried, the glue liquid is curled. Out of the gap; Some sealant and steel drums react after the internal reaction; Some sealant adhesive force is not strong, curling operation out of the curling. Therefore, the steel drum sealant must use quality assured products, otherwise the crimp quality is difficult to guarantee.
The glue spraying operation must be carried out at the bottom cover of the bucket in advance, and it must be allowed to dry for 24 hours before being used for curling. Because the wet film won't seal after being crimped, it will not be cured for a long time due to occupying the gap space. After the steel drum is impacted, it will easily flow out, resulting in leakage. Therefore, the pre-rolling glue application process must strictly control the quality. turn off.
Barrel-nose bonding process, in particular, should pay attention to quality, sealing should be tight and compact.
Most of the occurrences of leakage at the barrel mouth are due to the problem of the barrel mouth stamping die. The leakage of the mold may be caused by the aging of the mold, the change of the size of the mouthpiece, the quality of the seal ring, the reaction of the seal ring and the contents of the drum. Therefore, the stamping die must be replaced regularly; to purchase the uniform supplier's barrel mouthpiece, if the supplier changes, the mold must be redesigned; the seal ring must be complete, the size and size are the same; and the customer's costume goods must be studied. To ensure that the material of the seal does not chemically react with the goods and lose its sealing effect.
Some problems have also been found in the use of export steel drums. There are mainly the following types:
1. The quality of the inner coating barrel.
Some exports require the use of fully coated steel drums, or the addition of polyethylene liners inside the drums. These steel drums are relatively easy to leak, and must be filled with collars. Some inner coating buckets are used to hold foods, such as apple sauce, tomato sauce, honey, etc., because the inner coating does not meet the food hygiene requirements and contaminate the contents of the goods. Some paints are of poor quality and the coating falls off, causing rust on the inner surface of the barrel. Some food contamination is also caused by the use of special food sealants. These conditions should not occur, as long as the strict quality control in production, we can guarantee the quality of the inner coating of steel drums.
2. Steel barrel structure problem
The steel drums containing oils and fats are often placed in the open air. Some of the lid gaskets react with the contents and lose their sealing effect. They are also prone to leakage. In rainy days, the tight buckets are easily filled with water to make the oils deteriorate. This may be caused by the unreasonable structure of our steel drums, because the barrel mouth is lower than the outer edge of the barrel, so the water can easily seep. The international standard steel drum structure is such that the barrel mouth is higher than the barrel edge. Therefore, to completely solve this problem, we must only implement international standards as soon as possible, cite advanced technology, and change the unreasonable product structure.
3. Appearance problem
The color of paint on the outside of steel drums is generally filled with black grease. The colors of chemical raw materials are blue, green and brown. However, the steel drums produced by steel drum manufacturers have some differences in color, resulting in batches of steel drums. The color is not the same, which has great influence on foreign brands and packaging chemical products. It should be avoided as much as possible.
It is understood that most of the reasons for this happening are the faults of the paint suppliers. They supplied the paint to the barrel factory according to the batches. However, there are always differences in the colors of different batches and it cannot be guaranteed. To solve this problem, it is necessary to establish a long-term fixed relationship with the paint supplier, and to strictly control the quality of the paint. In addition, in the use of paint, try to mix evenly so that the paint color is the same.
4. Steel problem
Minimizing the cost of exporting and packaging steel barrels is a trend in recent years. At present, many manufacturers use coil materials to produce materials, which actually saves a lot of costs; in addition, the thinning of materials is also a way to save costs, but it must be stopped. According to the state of the arts and crafts of each company, new quality problems cannot be created.
In order to save costs, some manufacturers use a 0.8mm steel plate for 200 litre steel drums. Of course, this is not an option in one-off export packaging. However, it is necessary to consider the actual needs of the interior goods. Do not use the ultra-thin type. Steel plate. In addition, some manufacturers use steel plates with uneven thickness or corrosion, which also cause quality problems of different degrees. It is hoped that this situation will not happen again.