The application of welded structures makes the forging machine increasingly complicated (2)

3. The adjustment characteristics of metal cutting machine tool product structure and the development and development direction of new products

Metal cutting machine tools are machine tools for all machine tools. For this reason, the precision of the machine itself is high. In the past, due to the particularity of the cast structure, it has not been replaced by other structures. In recent years, with the research on welded structures and the development of welding technology, more and more welding structures have been applied to metal cutting machine tools, especially CNC machine tools. Such as: Jinan Second Machine Tool Group Co., Ltd. and the foreign production of SL242 CNC gantry milling and boring machine products, the total size of the equipment is 27.8 × 12 × 9.59 (m), the total weight of the machine: 250T. It: the beam and the column components are all welded. The CKX53150 CNC single-column mobile vertical milling lathe produced by Wuhan Heavy Machine Tool Plant has a column size of 3.21×3.59×9.66(m) and a weight of 83.5 tons. It also adopts a welded structure.

At present, the main components of the welding structure of the gold cutting machine tool are: bed body, crossbody, column and so on. They are the foundation and support for the entire machine, and other components are used to mount the base or to move on their rails. For this reason, the rigidity of the structure is required to be high, and the influence of thermal deformation on the machining accuracy is small and the stability is good. At the same time, it has good vibration damping. In recent years, through the improvement of welded structural components, the requirements of the performance of gold cutting machine tools have been met. At the same time, the welded structure has a wide range of applications in machine tool products. At present, the gold cutting machine tools that apply the welding structure mainly include: six large-scale metal cutting machines such as large-scale CNC gantry machining center, CNC floor boring and milling machine, CNC vertical milling and lathe, broaching machine, combined machine tool and hobbing machine.

4. The adjustment characteristics of metal forming machine tool product structure and the development and development direction of new products

Metal forming machine tools are mainly forging machinery products. This product has been the main product of the welding structure application in the machine tool industry. Since the 1980s, the welded structure has been applied to large parts such as bases, beams, sliders, columns, and work benches. At present, welded structural parts have also been applied to key components such as gears, rocker shafts and high-pressure cylinders of forging machinery products. For example, among the eight series of hundreds of presses produced by Jinan Second Machine Tool Group Co., Ltd., all the main structural parts and key components of J39 series, J47 series and multi-link presses are welded structure, and other series products The proportion of welded structure also reached 44.3%. Among them, the closed four-point double-action J47-1250/2000 tensile press has a welded structure ratio of up to 67.1%.

At the same time, the application of welded structures has made it possible to develop large-scale and complicated forging machine products. For example, the JG36-3000 double-point double-action mechanical press developed by Jinan Second Machine Tool Group Co., Ltd. has a total net weight of more than 900 tons and a welding body of 11×16×9.7 (m). The weight of the blank is 145 tons.

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Balance

1. Electronic balance and its classification According to the accuracy of electronic balance, it can be divided into the following categories:
1. Ultra-micro electronic balance: The maximum weighing of the ultra-micro balance is 2 to 5g, and its scale division value is less than (maximum) 10-6. For example, Mettler's UMT2 electronic balance belongs to the ultra-micro electronic balance.
2. Microbalance: The weighing of the microbalance is generally 3 to 50g, and its division value is less than the (maximum) weighing 10-5, such as the AT21 electronic balance of Mettler and the S4 electronic balance of Sartoruis.
3. Semi-micro balance: The weighing of semi-micro balance is generally 20 to 100g, and its division value is less than (maximum) 10-5. For example, Mettler's AE50 electronic balance and Sartoruis' M25D electronic balance belong to Such.
4. Constant electronic balance: the maximum weighing of this kind of balance is generally 100 to 200g, and its division value is less than (maximum) weighing 10-5, such as Mettler's AE200 electronic balance and Sartoruis A120S, A200S electronic balance The average is a constant electronic balance.
5. Analytical balance: In fact, electronic analytical balance is a general term for macro balance, semi-micro balance, micro balance and ultra-micro balance.

6. Precision electronic balance: This type of electronic balance is a general term for electronic balances with an accuracy level of â…¡.