Metal heat treatment is an important part of the mechanical processing industry, its processing mode in the industry mainly has two different types, different scale of production forms, one is a single small batch of order production, the other is multi-batch multi-batch mode. In recent years, with the development of the machinery industry, the heat treatment processing industry has been rapidly developed, but the technical level and management can not form a standard, can not get good economic and social benefits. As an enterprise to develop, improve the economic benefit, must under the premise that improves quality, reduces the cost of generalized analysis problems may exist in the heat treatment production, and to early for possible problems put forward countermeasures, through lean management, optimization of process and process, standardize operations, process standardization, after all, heat treatment quality is produced rather than testing out, win the trust of more customers, more orders to better reduce the heat treatment production cost.
Case: gear heat treatment
“5 QUESTIONS” MUST BE ASKED BEFORE HEAT TREATMENT
At present, in the production process of product orders in the processing industry, large-scale purchasers all have supplier development management evaluation, which requires on-site assessment and evaluation to make heat treatment production traceable. Heat treatment industry parts quality has its particularity, parts quality only in use or does damage to the metallographic test before inspection and testing, the products should be qualified timeliness, so we think to control heat treatment management center of gravity to move forward and backward, before heat treatment must be “may ask,” any artifacts into the heat treatment process to know:
Q1: What material is the workpiece, what kind of heat treatment should be carried out, and what are the technical requirements?
Q2: What will the workpiece be used for? What will the working environment be like? What are the technical requirements?
Q3: What process is done before the heat treatment of the workpiece?
Q4: When is the delivery time? After all, planning is necessary for the supply chain.
Q5: What process control should be paid attention to in the heat treatment process of the workpiece?
Case: Rack heat treatment effect profile
HEAT TREATMENT PROCESS FLOW SHOULD BE REFINED
The heat treatment process should be refined and analyzed in order to better control its process nodes and make products trusted by customers. Process refinement is node control, which is nothing more than the five factors we often say, namely people, machine, material, method, and link.
1. People
Due because the current market and production technology, the influence of heat treatment equipment, and also short of highly automated operation, people play an important role in the production process management, and so to all aspects of training for all heat treatment personnel, process, operation skills, safety, quality, and satisfied consciousness and form the KPI assessment mechanism to promote employees to learn and self-learning. In particular, we should pay attention to the training of staff operation awareness, (that is, according to the pattern, according to the rules, according to the process), reward self-effort learners. We do not require heat treatment site operation staff to become engineers, at least to become skilled technicians of heat treatment, do not take it for granted, the illegal operation caused by equipment damage and the process has not been well executed, so the personnel factor to control, in order to stabilize the quality of heat treatment.
In addition, the enterprise culture should be promoted, no matter it is a small enterprise or a department, so as to enhance employees’ trust in the company and cultivate them to have clear personal good development vision, so as to better achieve the win-win situation of cooperation between employees and the company.
2. The machine
The reliability of machine tool equipment is the material basis to protect the interests of the economy. It is directly related to the normal production cost, output, quality, and process continuity of the enterprise. Heat treatment workshop has many equipments, complex and unsafe factors, such as heating furnace equipment, electrical, cooling and mixing system, measurement and control instruments, etc., each equipment should establish the corresponding inspection daily ledger to prevent the equipment from working with disease, and immediately stop and overhaul if problems are found.
(1) Establish a full on-site inspection record for each piece of equipment, and master the equipment dynamics: operation, repair, maintenance, equipment on duty. The shift supervisor shall check and supervise the staff daily, cultivate good working habits of the staff, encourage them to work according to the rules, solidify good habits, and regularize the workshop management.
(2) For each equipment and each process operation, the heat treatment process operation standard book, the heat treatment equipment operation standard procedure, and the emergency plan for abnormal situations of the equipment shall be established.
(3) Optimize the tooling structure and quenching fluid management, inspect the tooling hanger every day to make it in a safe state, and avoid the phenomenon of unsafe factors; Irreasonable or serious deformation can not be repaired in time to replace the tooling hanger, reduce or avoid the resulting rework, deformation and other quality problems; Test and adjust the quenching liquid regularly to ensure the heat treatment quality of the workpiece.
3. The material
To clarify the workpiece before heat treatment, to understand the material status, such as processing status, whether there is a defect, bruise, whether there is oxidation, and forging and material status, etc., to provide chemical composition report if necessary. Through the check of the appearance, shape, and relevant effective size of the workpiece, it is convenient for the process personnel to take effective measures, appropriate process, and appropriate equipment to reduce the heat treatment distortion and avoid the early failure of the heat treatment. The raw materials used in the production process of each parameter meet the technical standards. The heat-treated parts, defective parts, and qualified parts should be placed in a fixed area, and clearly marked to prevent mixing and wrong materials. The planning process of each region should also conform to the process direction process, so as to reduce the ineffective handling and ineffective waiting time in the process as far as possible and reduce the waste of manpower.
4. Method
Heat treatment equipment energy consumption is relatively large, reducing energy consumption, improving equipment utilization, increasing product process rapid circulation is an important way to reduce cost and improve the economic benefit, so we as far as possible under the condition of equipment immobilization process using standard planning, process documents, etc., and according to the characteristics of the heat treatment process node set up corresponding working procedures, in order to reduce unnecessary loss.
(1) Establish the shift system. Heat treatment generally has the nature of continuous cooperative production and requires employees to have a high spirit of cooperation and a positive attitude to complete the work tasks on duty every day. Take mold heat treatment as an example: cleaning → charging → quenching → tempering → metallographic inspection → cleaning → delivery. The whole processing process needs to go through multiple shifts, and each step of work will have a related impact on the next process to the final technical quality. As a result, such collective processes need to have a paper-based transition system, and the responsible person on the shift must confirm with each other. At the same time, there should be corresponding management measures to stimulate the enthusiasm of employees and implement the responsibility system. In addition, on-site monitoring and control should also be increased to make employees consciously abide by the operating procedures at work, and provide a relevant analysis basis for later tracking.
(2) set up process wi, improve equipment operating procedures, to ensure that the heat treatment process is stable and similar products of similar materials technical requirements should prepare the corresponding working instruction, process details, instruction content should include the amount of furnace charging, charging mode, the main furnace process parameter Settings, cooling and tempering process, inspection procedures and unloading packing, etc. According to the standard operation, it will not affect the technical quality because of personnel changes.
(3) Database management, process operation records, and inspection results management should be established for each batch of heat-treated products of each batch of the furnace so that production control can be traceable and relevant personnel can consult, manage and track. It is also convenient for the relevant partners to feel that there are several, documented roles, especially as the heat treatment industry is usually a third party partner, through the ISO9000/TS16949 standard, enterprise customers often need to audit the factory review, outsourcing processing supplier evaluation cooperation is the need for relevant document database support.
(4) Heat treatment production planning, the process personnel should be involved in the organization of heat treatment production according to the production task period, batch reasonably, so that the workpiece can be reasonably adjusted, reasonable equipment allocation and effective arrangement of heat treatment workshop personnel on duty.
(5) heat treatment of workpiece are according to production plan target, according to the workshop of the plan, goal, task, layer upon layer decomposition, implementation to the relevant personnel, through the index decomposition monthly quantity, technical requirements, technical standard and staff operation procedures are listed in the form of kanban, every batch production tracking summary, let each relevant personnel heart have goals, work have the power, to the system to manage the production.
5. Process
Heat treatment is in a high-temperature working environment, generally should take into account the size of the plant, cooling, noise reduction, lighting, these factors directly affect the quality of heat treatment. Heat treatment workshop should have a certain height and span so that ventilation and process time can be guaranteed, and heat treatment may also produce a lot of lampblack, steam, etc., only reasonable space, reasonable operation can be guaranteed to a certain extent, to avoid staff misoperation and personal injury.”5S” in the area is the guarantee of clean and civilized production, which can make employees feel comfortable in the working area, have planning and rules, and can effectively prevent the occurrence of accidents such as material mixing and process misoperation, and reduce the chaos of the operation site. In addition, such as temperature, smoke, the noise will directly affect the operator’s sensory judgment, thus affecting the normal skill level of the operator and the correct implementation of the process, and then affect the normal production of heat treatment.
CONCLUSION
To sum up, the lean production of heat treatment should be people-oriented to save energy and improve efficiency, focus on technology and customers, and improve the periodic rate of heat treatment production. People, machines, materials, methods and rings are the main factors, of course, there are other factors. All factors are not independent, they are interrelated, interaction, heat treatment industry to do a good job in all aspects of scientific overall management, so as to produce the right products with the right equipment, the right quality, the right process, the right cost. Only by actively participating in the communication between industries or departments and winning their cooperation, support, and trust, can the internal and external production processes of the factory be smooth and convenient, and only by winning more market shares, improving industry visibility, and increasing market competitiveness, can the enterprise have good economic and social benefits.