How to determine the special process in the steel barrel production control process

Xin Qiaojuan

With the improvement of the market economy, customers are increasingly demanding product quality. The internal management of production enterprises directly affects the quality of their products. In order to produce customer-satisfied products and control the production process in an orderly manner, enterprises have implemented quality management system certification. Through the effective implementation and continuous improvement of the quality management system, customer satisfaction is finally achieved, so as to gain more market share. Steel drum enterprises are no exception. Many enterprises have established a 2000 quality management system based on the ISO9001:2000 quality management system based on the original ISO9001:1994 quality management system.

However, many companies often have certain deviations in determining the special process (process) in the production process of steel drums, so that the quality system is in an uncontrolled state here. In order to solve this problem, the author concludes through long-term work practice. A few rules, in this case, with the peers to discuss, in order to attract jade.

The foundation and terminology standards of the ISO 9000:2000 quality management system clearly state that a process is a group of interrelated or interacting activities that convert inputs into outputs. Any product in the enterprise is completed by several processes of different sizes. The special process refers to whether the formed product is qualified, the process of testing or verification is not easy or economical, or the result of the process cannot be completely verified by the process of testing and testing the product, or the problem of product use and service delivery. the process of. The quality of the process of a special process is often difficult to test. Quality hazards or quality problems are not easy to find. Once accumulated to a certain extent, a large number of non-conforming products will be produced, resulting in loss of product quality. Therefore, the quality of the process of a special process directly affects the final quality of the product and is related to the economic benefits of the enterprise. Special processes are generally also key processes, but the key processes are not necessarily special processes. Determining special processes and controlling them effectively is one of the effective ways to improve the quality of enterprise products.

Then, how should steel drum companies determine their special processes in establishing a quality management system? What criteria are used to determine what is a special process and what is not a special process? What method should be used for control?

1. Processing defects that can only be exposed after subsequent processes or after use

This process is most pronounced in the production and processing of steel drum companies. For example, the welding process of the steel barrel body, the welding quality of the process in the barrel welding process: whether there is welding defect, whether it is leaking, whether the welding is firm, etc., can not be inspected or verified in the process, must be under Once a process or product is finally put into use, its defects can be discovered. In the past, steel drum manufacturers were only able to conduct leak tests after the steel barrels were formed and formed, and the non-conforming products of the process could not be controlled at all. In recent years, with the improvement of customer requirements and the increasing awareness of the quality of the barrels, most steel drum companies have added a pre-leakage process control in the production process control, but this process control is only after the welding process is completed. get on.

The second is the barrel barrel and the bottom (top) sealing process, which can also be called the assembly process of the steel drum. The assembled steel drum belongs to the metal packaging container, so it should have certain strength, pressure resistance and no leakage. Whether these properties are available or not can not be directly reflected in the process control of this process, and only through a series of inspection methods such as leakage test, drop test, air pressure test, and water pressure test in the subsequent process can be verified. Therefore, the special process of the steel drum has higher technical requirements for the operators, and generally should be trained to obtain the operation certificate of the special process operators before they can be employed. For such special processes, control charts or process capability index analysis methods should be used for quality control to ensure that the process capability meets the specified requirements.

Second, the process of processing products can not be measured

The process in which the product cannot be inspected by instruments such as monitoring and measuring devices. For example, the welding strength of the steel barrel barrel weld can not be tested after the welding process is completed. Therefore, after the barrel is welded, it is impossible to determine the quality of the barrel or the final product steel drum. It can only be inspected and tested after it has been completed through the subsequent processes. For this special process, the operator must be careful and careful not to speed up and grab the time to adjust the various process parameters in the welding process. This special process generally requires regular or irregular inspections, inspections of the operator's work attitude and mental state. Once an abnormality occurs, the operation should be stopped immediately. To find out the reasons and take corresponding measures to ensure that the operator is comfortable, relaxed, and emotionally stable before proceeding.

Third, the inspection costs after processing require a larger process

The products formed by this process have a long product inspection cycle, and the accuracy requirements for the use of monitoring and measuring devices are relatively high. The manpower, material resources and financial resources used are relatively high, so the inspection cost is relatively high. For example, the assembly process of the steel drum, that is, the sealing process of the barrel body and the bottom of the barrel (top). Whether the assembled steel drum leaks, only after passing the special non-leakage inspection equipment, can it be judged whether it is qualified, of course, the process inspection must be carried out, and the corresponding manpower and resources must be equipped. For such process control, continuous monitoring and measurement of the process should be carried out using statistical techniques and tools such as control charts.

4. Processes that require destructive testing to verify or verify the product.

This special process is that after the product has been inspected or tested, the product no longer exists. The more the test is, the more it is consumed, and the higher the inspection cost. In the production process of the steel drum, this process occurs in the assembly process of the steel drum, that is, the sealing process of the barrel body and the bottom of the barrel (top). To test the performance of the steel barrel edge layer, the tightness of the package, the strength of the seal and the weld strength of the barrel, it is necessary to test the performance of the steel drum. The performance test of the steel drum is a destructive test. For example, the water pressure test, the airtight test, the drop test and the stacking test. After these tests are completed, the steel drums become waste products, and the original use performance is lost, that is, the steel drums are no longer present. However, in order to test the packaging category of steel drums, especially the metal packaging steel drums used for dangerous goods, this performance test is indispensable, only by doing this destructive performance test, that is, to make a drop test (divided into a corner drop) Peaceful fall, the main reason for the decline is the quality of the curl after the seal is sealed; the flat drop is the quality of the weld after the barrel is welded, the hydraulic test, the air tightness test and the stacking test, we can identify The category of dangerous goods in steel drums is the steel drum for the packaging of dangerous goods of Class I (the drop height is 1.8 meters, the water pressure test is 250KPa, no leakage for 5 minutes; the airtight test pressure is 30KPa, no leakage for 5 minutes). It is also a steel drum for the packaging of Class II and Class III dangerous goods (the drop height is 1.2m and 0.8m respectively, the hydraulic test is 100KPa, no leakage for 5 minutes; the airtight test pressure is 20KPa, no leakage for 5 minutes).

The above is based on my own practice on the production process of steel drums, and I understand the personal views expressed by some steel drum enterprises when they set up the ISO9001:2000 quality management system and set up a special process. The method of determining a special process is briefly discussed from four aspects. As long as a process has the characteristics of the above four aspects, we believe that the process is a special process and should strictly control and ensure the processing capability of the process. Of course, some processes not only have one aspect of the characteristics, but also have two aspects (such as the welding process of the steel barrel body), and even four aspects (such as the steel drum's winding, that is, the assembly process of the steel drum). For such processes in the production and processing of steel drums (ie welding and sealing of the barrel), it is necessary to strengthen the inspection, key monitoring and prior prevention, and use statistical techniques and tools to test the process parameters of these two special processes. The detected data is statistically analyzed, and corresponding measures are taken according to the results of the analysis to ensure the processing capability of the special process to prevent abnormal phenomena and cause leakage of the steel drum. Only in this way can we reduce or eliminate the leakage or scrapping of steel drums, and finally achieve the purpose of improving the quality of steel drum products.