Category: Manufacturing Technology knowledge

Machining error refers to the degree of deviation between the actual geometric parameters (geometric size, geometric shape and mutual position) and the ideal geometric parameters of a part after processing. The degree of conformity between the actual geometric parameters and the ideal geometric parameters after part machining is the machining accuracy. The smaller the machining error and the higher the degree of conformity, the higher the machining accuracy. Machining accuracy and machining error are two ways to address the same problem. Therefore, the size of processing error reflects the level of processing accuracy. The main causes of machining errors are…

In the heat treatment process, the scrap rate caused by the quenching process is often high, which is mainly due to the large thermal stress and organizational stress formed at the same time during the quenching process. In addition, due to the inherent metallurgical defects of materials, improper material selection, wrong materials, poor structural and technological properties in design, defects formed during cold and hot processing, and other factors, they are easy to be exposed in the quenching and tempering process, so the quenching The defects after tempering must be systematically classified and inspected. Quenching defects and prevention The most…

The setting principles of safety protection devices are as follows: First, based on the plane on which the operator stands, all moving parts with a height of less than 2m shall be protected. Second, based on the plane on which the operator stands, if the height is more than 2m, there are material transmission devices, belt transmission devices and the lower part of the construction machinery, protection should be provided. Third, protection shall be provided at the operation position 2m above the falling height datum plane. Fourth, in order to avoid crushing injury, the distance between linear moving parts or…

1. What problems should be paid attention to when using new oil in the tank? Before pouring new oil, the quenching oil tank and cooling system must be carefully checked and cleaned. The remaining water, oil sludge and other dregs should be cleaned up. When adding new oil to the old oil tank system, the oil stain on the tank wall above the oil level in the quenching oil tank and on various frames should also be removed and cleaned. If the original oil residue and sludge are mixed with the new oil, the cooling characteristics of the oil may…

In the field of industrial production, the main types of nodulizing agents are magnesium silicon alloy, rare earth magnesium silicon alloy, calcium alloy (mostly used in Japan), nickel magnesium alloy, pure magnesium alloy, rare earth alloy (mainly light rare earth with cerium and lanthanum and heavy rare earth with yttrium), etc. At present, rare earth magnesium ferrosilicon alloy is the most widely used alloy in the world. In addition, single light rare earth nodulizer (mainly cerium and lanthanum), single heavy rare earth nodulizer (mainly yttrium), barium containing nodulizer, antimony containing nodulizer, bismuth containing nodulizer, copper containing nodulizer, etc. are derived.…

At present, foundry enterprises give priority to medium frequency induction furnaces due to environmental protection, charging, human resource costs and other reasons. Its development trend is intelligence, high reliability, high quality, high-quality service, energy conservation and environmental protection. Especially in multi brand production foundry enterprises, the advantages are more prominent. In the current situation, the following are the requirements of enterprises, which should also be considered when selecting models. (1) Increase the specific power and control the power consumption at 600kW/t. (2) The furnace body, power supply system, cooling system and tilting furnace system are of high quality, good reliability…

Alloying treatment of cast iron can be traced back to the 1930s and 1940s. Alloying treatment has made a qualitative leap in the properties of cast iron. At the same time, some special purpose cast iron such as wear resistance, corrosion resistance and heat resistance have also been born. It was also during this period that cast iron was produced by inoculation. In the late 1940s, the cast iron with spherical graphite after inoculation replaced the ordinary sheet graphite cast iron. We call this type of cast iron ductile iron. Classification of spheroidizing and anti spheroidizing elements Spherical elements are…

1. Bending time definition and its constituent items 1.1 Bending man hour refers to the man hour for bending in the workshop. 1.2 Bending man hour consists of preparation man hour, operation man hour and auxiliary loading and unloading man hour. 1.3 Preparation time refers to the time consumed to get familiar with process documents, get materials, adjust the bending machine, etc. 1.4 Operation man hour refers to the time consumed for bending. 1.5 Auxiliary loading and unloading man hours refer to the time consumed for loading and unloading. 2. Calculation regulations for each component item of bending man hour…

The maintenance of the continuous die must be careful and patient, and it must not be blindly carried out. When the die is repaired due to faults, the tape must be attached to facilitate the query of problems. Open the mold, check the mold condition, confirm the cause of the failure, find out the problem, and then clean the mold before removing the mold. The force shall be uniform when removing the mold. For the mold structure where the stripper spring is between the fixed plate and the stripper plate and the stripper spring is directly pushed onto the inner…

Wear is a very common phenomenon in machining process, which may be caused by many factors, such as workpiece material, environment, processing method, etc. Mechanical wear will have adverse effects on the processing quality, precision and efficiency of products. Therefore, for those who are engaged in machining industry, it is very important to do a good job in the prevention of mechanical wear. Common types and characteristics of mechanical wear The common wear types in machining mainly include running in wear, hard grain wear, surface fatigue wear, thermal wear, phase change wear and hydrodynamic wear. Running in wear is the…