China National Institute of Standardization on June 4 published recommended national standards called the Workpiece Machining Energy Consumption Limit Setting Method (draft for comments) (the “Standards”; 机械加工制造过程工件能耗限额制定方法 (征求意见稿)). This draft is open to public comments until August 2.
According to statistics, the energy efficiency of machining operations in China is lower than 30 percent while there are over 7 million “main frame + lathe” style machine tools for workpiece machining. The country doesn’t have an applicable method to set energy consumption limits for machining operations yet. Under these circumstances, the latest draft standards have been developed to improve energy efficiency in the manufacturing sector. Here is an overview of these standards.
The standards define general rules, the setting method and the use of workpiece machining energy consumption limits.
Limit setting method for workpiece machining energy consumption
The limit on workpiece machining energy consumption is set using this equation:
[energy consumption limit] = [total power consumption of workpiece machining operation per lot for a given period] ÷ [number of approved items] × [coefficient based on the company’s energy usage level]
Use of workpiece machining energy consumption limits
It is recommended that workpieces be ranked according to energy consumption limits calculated using the above method so that machine tools consuming more energy can be identified and then removed or replaced with more advanced technology.
The draft standards’ description document says these standards will play an important role in improving energy efficiency in green production/manufacturing defined by the Guidelines for Assessment of Green Factory (绿色工厂评价导则), and in improving green products’ compliance with energy efficiency standards.
The full text of the draft standards (in simplified Chinese) is available at