The gap in China's valve industry is obvious

Although the valve industry in China has developed rapidly in recent years, the overall level of the industry is still low, and the technical content of products is low. Many key valves with high parameters also rely on imports. Some experts estimate that China's valve level is 10 to 20 years behind that of foreign advanced countries. Not long ago, China's valve industry to strengthen the exchange with the European valve manufacturing industry, has organized the more than 10 veterans of domestic valve companies to visit Europe, learned the valuable experience of many foreign counterparts, and compared with foreign valve industry, also saw Our own shortcomings.

Disparity in the processing technology In the welding process, Germany KSB company to meet the requirements of radiation resistance of the sealing material of nuclear valves, has been widely used special welding powder for cobalt-free welding; France Wellan Valve Company will preheat, automatic welding The post-weld treatment is completed on the same equipment or on the same processing line. No matter pre-welding, welding or post-weld treatment, the temperature can be automatically controlled to ensure the welding quality.

The domestic process behind the valve welding process, some also use the old welding method, the welder technology level is low, the welding material is also an ordinary material, can not reach the special valve design requirements. A lot of companies are busy with production and sales all day, and they rarely make improvements in the process.

In the application of new technology for die forgings, the KSB company produces valves made of high temperature resistant alloy steels F91 and F22. The high pressure valves are mainly made of forged parts to ensure the reliability and economy of the products. For large batches of 600Lb or less gate valves with forging and welding, the valve did not cause many defects such as porosity, looseness due to casting, and greatly reduced the waste of free-forging materials, greatly improving economic efficiency.

In the domestic industry, most of the valve blanks are made of cast parts, and die forging is rarely used. Valves with a high pressure below 600 Lb can be said to be extremely rare. In order to reduce costs, many enterprises in this area mostly use cast steel parts, low-pressure cast iron parts, low material cost, and simple processing technology.

The gap between quality management and equipment France's Bernard electric device company sales in 2005 was 300 million yuan, exports accounted for 70% of sales, established a global sales network, China's metallurgy, paper, water treatment and oil and gas pipelines The valve used a large number of the company's electrical products. In the field of nuclear power, their supply ranks second in the world, and more than 70 nuclear power plants in France use their products. Their management is in place. The company's parts processing records are transferred along with the parts. The production site is neat and tidy. The two assembly lines are working in an orderly manner. Their screw processing adopts rolling method, high efficiency, and high surface finish of parts. The processed parts are cleaned in a timely manner, and the station equipment is properly applied. For example, a plastic bag is placed on each shaft, which is very simple but practical. It avoids scratches and scratches between parts. The coating method of the parts is similar to that of the domestic ones, but because the blank itself is smooth and the quality of the paint is excellent, the product after the painting has a very good appearance and quality.

In comparison, there are still many defects in quality management in China. First of all, the process is more or less neglected. Many companies clearly have a quality assurance system, but they can't use it in actual work. Quality management implements itself and is arbitrary. Secondly, it is a sloppy thing in the assembly process. It is no wonder that some valves have appeared running, running, dripping or leaking as soon as they are installed.

Another example is the backwardness of many domestic enterprises' production equipment, which has remained at the level of the 70s to 80s of the last century. Some equipment has already passed the service life and is still running at full capacity. How can the quality of product processing be guaranteed? Some of them are limited to funds and they are gradually adding CNC and machining centers. However, the number of enterprises that form CNC machining has not been large in the industry so far, accounting for only about 20%.

Disparity in process management The layout of the equipment of the French company Weyland is carried out according to the product process route in order to achieve the shortest processing route, so that the operator can complete the workpiece processing within the minimum range of motion.

They have adopted a large number of processing centers and even five-axis linkage flexible machining centers, CNC turning and milling machine tools and CNC machine tools, the computer-aided manufacturing into a line, the product in a device clamping, programming once. The programming work can even be remotely operated in the office, which simplifies the machining process. The engineers and technicians only need to program the program and select the appropriate tool to ensure the processing requirements of the product and make the product high quality and high efficiency.

Similarly, the production process of Italy's New Guinean company is characterized by: after receiving orders, the design and development center will be transformed to provide technical documents such as product design drawings, outsourced outsourcing details, and machining procedures, which will be transmitted to all relevant departments through the internal network. The production department organizes production according to technical requirements and sales orders. After the blanks are brought into the factory, the warehouse personnel will send the blanks and other parts to the various processing and assembly sites according to the production plan. They are not all self-produced, and many are also purchases. However, almost all of their product components are completed on numerical control equipment with high machining accuracy and high processing efficiency. Employees can read the parts processing drawings and parts processing programs on the console of the CNC machining equipment. He only needs to press the workpieces to the CNC equipment according to the processing technology requirements, start the processing program, and can automatically complete the car, drilling, milling,é•— and other processing processes.

However, many domestic valve companies are not professional, small and complete, products are mixed, processing valves are chaotic, the layout of workshop processing equipment is unreasonable, and parts and components are not stacked. At present, the domestic piece-rate working hour system is widely used, but there are also similar problems and the working hours are unreasonable. Most of them also use the original manual records to collect settlements. It is precisely due to the limitations of some enterprise process management levels, resulting in low product technology levels, lagging processing technology, and serious waste of raw materials.

In addition, the layout of domestic machinery processing equipment is mostly arranged according to the type of equipment, such as the arrangement of machining centers, horizontally placed in a row, vertical in a row, CNC machine tools in a row, this arrangement only consider To the site neat, without considering the ease of operation, labor efficiency is low, the cart before the horse.