Investment casting production mainly includes four processes: module preparation, shell preparation, alloy melting and casting post treatment. Because the process method is not only various processes, product flow Complex, long production cycle, and the casting process is very professional. Therefore, the consumption of production materials from input to output is not intuitive and clear, and the variety of use is complex and the amount is not easy At the same time, due to the different casting process yield and yield, as well as the increasing investment in dust removal and environmental protection, led to the investment casting enterprise cost analysis and cost control The system is more difficult.
1. Basic composition of production cost of investment casting enterprises
The production cost of investment casting refers to the cost directly related to the production and operation of enterprises The production cost of investment casting is divided into material cost, direct labor cost and manufacturing cost. Environmental costs are separately included in the production costs of investment castings.
1.1 Material cost
The cost of direct materials used by enterprises in the process of manufacturing products is collectively referred to as material cost, which can be divided into various raw materials and main materials that constitute the main entity of products according to different functions. Fuel and power consumed by the process; Combined with the main entity of the product, or contribute to the formation of the product and consumption of auxiliary materials.
1.2 Direct Labor
Refers to the wages and welfare of production workers who directly participate in manufacturing products.
1.3 Manufacturing Expenses
Refers to the various administrative expenses incurred by each production unit of investment casting enterprises for the organization and management of production, as well as the maintenance costs and depreciation costs of machinery and equipment.
1.4 Quality Cost
Quality cost refers to the total cost of the enterprise in order to ensure the stipulated product level and total quality management, as well as the loss caused by the failure to reach the stipulated quality standard.
1.5 Environmental Costs
Environmental cost refers to the cost taken or required to take measures for the impact of casting production on the environment in accordance with the principle of being responsible for the environment, as well as the implementation of environmental objectives by enterprises Other costs paid by standards and requirements mainly include the following aspects 1) the cost of reducing pollutant emissions (2) the cost of waste recovery, reuse and disposal (3) green procurement cost (4) environmental management cost (5) social activity cost of environmental protection (6) environmental loss cost
2. Investment casting production material cost accounting
Material cost is the main component of investment casting cost. In the actual production of casting, a batch of material is often consumed by a variety of castings. How to make the material cost reasonable
The aggregation and distribution of different products is worth thinking about. According to the process flow of investment casting production, the material cost can be collected and distributed in mold consumption and mold shell Material, charge consumption 3 main aspects.
2.1 Mould consumption
In investment casting, the die material can be recycled. Mould consumption in production mainly consists of recovery loss and residual wax burn loss. When the mold processing process is basically fixed, it can be measured Calculate the consumption quota and cost accounting.
2.2 Type shell material consumption
Shell materials include refractory powder, sand, binder and so on. The raw materials consumed for shell making are related to the surface area of the shell. When the shell material, coating layer number and process is certain, you can use the mold Group surface area or type shell weight to allocate material cost.
2.3 Charge consumption
The metal material of investment casting is melted in accordance with the furnace. When calculating the charge input, the furnace is taken as the unit, and the metal ingredients and castings of each furnace are recorded according to the “furnace number” Species and quantity.
2.4 Cost accounting of casting materials
Through the above accounting, we have calculated the cost of mold loss for a certain type of casting single product, the cost of consumable shell material for production of single product and the cost of metal material for unit product.
3. Ways to control the production cost of investment casting enterprises
In the whole investment casting production cost of material cost is the largest proportion and influence, so the control of material cost is the focus of the whole cost control. In general, Direct labor and manufacturing cost have little influence on production cost, but in special cases, quality cost and environmental cost, such as process yield rate and reject rate, also have great influence on production cost Impact. For the factors affecting the production cost of enterprises, it is necessary to formulate targeted control measures.
3.1 Reduce material consumption
In actual production, the materials within the process quota shall be prepared and allocated according to the production plan, and the materials not directly used in product production not within the consumption quota shall be checked step by step Batch distribution, by saving the field material to improve the material utilization rate, by optimizing the process to carry out a scientific and reasonable ratio of materials, to reduce the ratio of new materials innovation The cost.
3.2 Improve process yield and reduce casting reject rate
Process design and site management are the two major factors affecting the process yield. Process reform should be carried out through process verification before mass investment and training of high quality process designers Innovation, to improve product performance and process yield, reduce product cost. By improving the pouring accuracy of the casters and optimizing the field process, the utilization rate of alloy liquid can be improved. Optimize site management.
3.3 Save energy and reduce energy consumption
The energy consumption of the foundry industry accounts for 23%~62% of the energy consumption of the machinery industry. The energy consumption is mainly coke, coal and electricity, followed by compressed air, oxygen and water. Foundry industry in China The energy efficiency is only 15%~25%. For example, smelting equipment and smelting energy consumption account for about 50% of the energy consumption of the whole casting production. Improving backward smelting equipment can reduce the energy consumption of casting production The key.
3.4 Strengthen environmental protection and promote the treatment and recycling of casting wastes
The recycling of waste not only reduces the loss of relevant materials, but also directly reduces the cost. At the same time, from the perspective of environmental cost, the waste treatment problem is in the casting cost saving Such as the final treatment and recycling of the waste sand cleaned after casting shell, saving cost, reducing energy waste and reducing environmental pollution.
3.5 Improve labor productivity
Increasing Labour productivity can reduce the fixed costs per unit of product. Improve labor productivity, it is necessary to constantly improve the level of mechanized production, the use of new technology, new Process, to achieve specialization.
Post time: Aug-26-2021