When it comes to quality, our seal manufacturers will first think of quality management system and quality inspection center. Because they are the guarantee of product quality. Why do many seal manufacturers have quality assurance department, customers often complain about the quality of seals? Learn and master the knowledge of quality management, the quality of seals is guaranteed? To answer these two questions, we must first figure out The particularity of seal quality management. After comparing with many industry customers, through comparative analysis, we summarize the following differences:
First, the "seal" requirement determines that the seal must be an elastomer. This is different from the rigid size requirements of the general manufacturing industry. Of course, a professional seal manufacturing company has reserved tolerances in the design and tested according to tolerances, but the products in the actual application are compressed. That is to say, the size of the component for quality inspection is not the size of the seal actually used, which greatly increases the difficulty in designing and detecting the seal.
For example, when our seal manufacturers design and test seals such as hydro-pneumatic seals, oil seals, O-rings, etc., they can only detect the size before compression, and the detection accuracy is extremely limited. For the seal size that actually works after compression, and compression After the performance changes produced, its quality detection is difficult. Similarly, for mechanical seals, gaskets, packing, and even more seals, they must be compressed to provide a seal. For large-size seals, quality inspection and inspection designs are more difficult. Although the design and production of each seal has quality process control, there are still some differences between the quality of the product and the actual quality of the seal.
Secondly, the seal is a product with a large number of batches, a small amount, and a variety of materials and materials. This is very different from the quality system requirements of mass-produced manufacturing companies, such as automobile manufacturers.
Our seal manufacturers use the most basic working units – the sealing system for pipes, valves and pumps – to use at least mechanical seals, gaskets, oil seals, packings and O-rings, and for different acid-base media. Conditions such as high temperature, low temperature, high pressure and vacuum require different sealing materials to be manufactured. The combination of sealing form and material is very complicated, which makes the design and testing standards of sealing parts more complicated. That is to say, in the production process, because of the use of special raw materials, special production processes and special equipment, the quality of the seals is therefore custom-made or experimental. Since the sealing industry has developed with the advancement of industrial basic equipment, and the seal is on the edge of many industries, and most engineering colleges in China have not yet opened the discipline of sealing technology, the basic theoretical research is weak and lacks quality basis. Therefore, many sealing parameters are still lacking, which increases the difficulty of quality control and evaluation of sealing products.
Finally, the seal is an extremely useful "accessory", that is, it must work with other equipment. The seal is not easy to use, not only the quality of the seal, but also the state of working with the equipment it is equipped with. For example, the sealing quality of the valve of the seal manufacturer can only be judged when the valve is working. If it is a new valve, the quality reliability will be much higher. If it is an old valve with poor precision, the probability of quality degradation will be large. some. Another example is the seal of the pump, which only knows if it is working properly when the pump is working. This is the reason why many users judge the deviation of the seal quality.
