Four Anhui local standards, such as the determination of multi-point thermal error on the workbench of precision numerical control machine tools, were implemented in July

Local standards are approved and issued by local (provincial, autonomous, municipal) standardization authorities or professional authorities, and uniform in a given region. The formulation of local standards is generally conducive to the development of regional advantages, is conducive to improve the quality and competitiveness of local products, but also make the standards more in line with local reality, conducive to the implementation of standards.

On June 22, 2020, Anhui Institute of Metrology and Science declared the "Hospital General Energy Consumption Limit and Calculation Method" (DB34/T3598-2020), "Technical Specification for Integrated System sedumic sedation of heating metering for civil housing" (DB34/T 3599-2020), "Precision CNC Machine Tool Workbench" The determination of spot thermal error (DB34/T 3600-2020), "Measurement of thermal error in the real-cut state of precision numerically controlled machine tools" (DB34/T 3601-2020) four provincial local standards were approved by the Anhui Provincial Market Supervision Administration and will be implemented on July 22, 2020.

Heating metering is based on the premise of central heating or district heating, in order to adapt to the user's thermal comfort needs, enhance the user's awareness of energy conservation, to protect the interests of both sides of heating and heating for the purpose of achieving household metering and charging through certain heating control technology, metering means and charging policy. Simply put, heating metering is to charge heating fees according to the amount of heat used, that is, how much heat, how much to pay. Domestic heating metering mainly has the following ways: thermal distribution metering method, household heat meter method, flow temperature method, break-off time area method and temperature area method.

Heating metering temperature control integrated system.

It is a collection technology system that integrates heating system control, metering and room temperature control, which integrates the system control, metering and sub-house temperature control platform unified management, realizes intelligent heating metering, system control automation, household heat autonomy, and scientific government supervision. The system consists of hardware and software equipment such as heat meter, intelligent temperature control valve, intelligent thermostat, data acquisition terminal, heating data management system, etc., and can realize the first/second level networking scheme.

Precision CNC lathes.

It is an automated machine equipped with a program control system. The control system can logically process the procedure with control coding or other symbolic instructions, and code it, and use coded numbers to indicate the numerical control device through the information carrier. The operation and processing by the numerical control device issues a variety of control signals, control the movement of the machine, according to the shape and size required by the drawing, automatically process the parts out. Is a typical mechatronic product. The machining accuracy of the ordinary CNC machine tool has been increased from 10 to 5 m, the precision-stage machining center has been increased from 3 to 5 m to 1 to 1.5 m, and the ultra-precision machining accuracy has begun to enter the nano-scale (0.01 sm). In order to achieve high-speed, high finishing, with the supporting functional components such as electric spindles, linear motors have been rapid development, the application field further expanded.

Machine workbench use.

The machine tool workbench is divided into boring milling machine workbench and so on. Mainly used for machine tool processing work plane use, with holes and T-slots, used to secure workpieces, and to clean up iron chips produced during machining. Products made into rib plate and box type, work surface using scraping process, work surface can be processed V-shaped, T-shaped, U-shaped grooves and round holes, long holes. Machine tool bench material: after two manual treatment (artificial annealing 600 degrees-700 degrees and natural aging 2-3 years) using the product's accuracy is stable, wear performance is good. Moisture resistance, corrosion resistance, non-fading, low temperature coefficient and so on.

The thermal error measurement of CNC machine tools.

The difference between the actual response of the machine in accordance with a certain operating procedure instruction and the expected response of the operating procedure causes the machine to be thermally deformed. Deformation error is the largest error source of CNC machine tools, accounting for 40% of the total error, so the problem of accuracy reduction caused by thermal deformation is becoming more and more prominent, so thermal error control will be the key technology to improve the precision of precision machine tools, especially precision high-speed CNC machine tools. The main influencing factors of machine tool thermal error are internal heat sources, and various heating elements include electric motors, frictional motion and cutting heat. Among them, frictional motion, such as gears, bearings, such as the heat effect is the greatest.

The law of thermal deformation of the machine tool is related to the temperature change of many important components on the machine tool. A certain number of temperature measurement points must be arranged on the machine to measure the overall temperature of the machine, through data processing and calculation, in the machine to find several and thermal deformation correlation of good important temperature measurement points, and ultimately used for thermal error modeling.

The thermal deformation displacement field is a function of multi-temperature variable, and the neural network model and the multi-regression model can better describe the thermal error law corresponding to the temperature change of the machine tool. The ways to reduce the thermal error of the machine tool are structural optimization, reducing heat source, isolating heating elements and real-time temperature measurement compensation. The use of numerical control devices to compensate for thermal error is best done after the previous measures.