Lean manufacturing study of honing process

This paper introduces the principles and characteristics of honing processing and the production problems that exist in honing processing, which can have an impact on the delivery of products. Using the guiding ideas of lean production, targeted solutions are developed to stabilize the machining process, improve production efficiency, promote on-time and timely product output, reduce waste, and enhance corporate competitiveness.

Aerospace component products need to meet the precise action control, so they require stable assembly size, strict shape and position tolerance, especially the bore that needs to be assembled, which generally has high cylindricity and surface roughness requirements. Honing processing can achieve high dimensional accuracy and surface roughness, and is widely used in the finishing of components. Studying the lean production method of honing machining can improve the quality of honing machining, stabilize the machining process, improve the productivity and promote the output of parts.

Principle and characteristics of honing process

Principle of honing processing

Honing processing is to use a number of oil stones mounted on the honing head, with a tensioning mechanism The structure will open the oil stone along the radial direction and make it press to the hole wall of the part; at the same time, the honing head does the rotating movement and the straight line back and forth. honing head does rotating motion and linear reciprocating motion to grind the hole at low speed for friction polishing. The result of the rotating and reciprocating motion is that the abrasive grains on the oil stone on the hole surface The result of the rotary and reciprocating motion is that the cutting trajectory on the hole surface is a crossed and non-repeating pattern, resulting in a high surface quality. The radial pressurized motion is the feed motion of the oil stone, and the higher the pressure, the higher the feed. The processing principle and processing reticle are shown in Figure 1 and 2.

Characteristics of honing processing

Honing processing has the following characteristics compared with general cutting processing: first, it can obtain high machining accuracy, secondly, it can obtain high surface quality, thirdly, its machining The range is wide. 2.

Problems of honing

There are some problems in the production of honing, which are mainly manifested as the following points.

Generate unqualified products

Honing head has different structure forms, and it has different connection methods with machine tools. Different structural forms and connection methods have influence on the parts, which may lead to Non-conforming products, i.e. the dimensional or form tolerance of the machined parts cannot meet the requirements of the drawings.

Uneven demand of production capacity

Honing processing is a special processing, only some parts need this process, when customer’s order changes, it may lead to tight capacity demand in a certain period of time.

Figure.1 Machining principle diagram

Figure.2 Machining reticle
The task is too much; in a certain period of time, the task of honing process is less and workers have no parts to process.

Few honing operators

The company is currently equipped with only one full-time operator for honing equipment, and other other personnel do not operate the honing equipment, and there are many problems with such a configuration. When the dedicated dedicated operator can not work properly, it will lead to production stagnation and cause processing delay. The work is delayed.

Inconsistent processing tempo

When determining the honing process parameters, there is no coordination between the machining allowance, machining material, tool material, honing head structure, and honing head structure. tool material, honing head structure and form, resulting in honing work The problem of inconsistent machining tempo exists when the structure type of similar parts is processed in the honing process.

Measures for lean production of honing process

The goal of lean production is to eliminate all waste in the production process, improve efficiency, reduce costs, eliminate handling, inventory, and so on. efficiency, reduce cost, eliminate handling, inventory, machining process, waste of non-conforming products, etc. Based on the characteristics of aviation products, the features of honing processing, the concept and objectives, the promotion of lean production method of honing processing can be done by the following measures Complete.

Change of production method

Implementing pull production

In the pull production mode, the delivery time is the final point, and each process is to present the demand to the previous process according to the demand at that time, the whole process is equivalent to the whole process is equivalent to pulling from the back process to the front process, so it is called pull production. According to the pull production, the The processing time of each process is clearly defined, and just-in-time production is realized.

Production Planning with Kanban

Kanban is a tool for just-in-time production, which has the functions of guiding operations, realizing It has the function of guiding work, achieving production management, and improving the site. Kanban contains information on production quantity, time, and The management can see the priority of production at a glance. Operators The operator produces according to the products and quantities shown on the Kanban, i.e., according to the necessary items, time, and quantities. The operator produces according to the products and quantities shown on the signboard, i.e., according to the necessary items, time, and quantity.

Standardized work

Standardized operations are designed to achieve the best possible arrangement of workers, work sequences, process equipment, and logistics. The standardized operation is an operation standard established to achieve the optimal combination of work personnel, work sequence, process equipment arrangement, logistics process, etc. The purpose is to produce the best quality products at the lowest cost. Standard work is Lean production is the basic content of manufacturing, improvement and management. To realize the standardization of honing standardized operation, mainly from the following aspects to improve.

Standardization of machining process

The standardization of machining process helps the process personnel to ensure the uniformity of process documents when preparing the process, and promotes the promotion of group technology, the formation of standard operation, and the operation of standard processing unit. Using standardized process documents, their product process control will be more stable, and the processing process will tend to be consistent and improve processing quality. The following figure shows the standardized process of two similar products.

Figure.3 Standardized process of honing process

Standardization of fixtures

Standardized fixture can realize quick changeover, reduce downtime and Improve equipment utilization and speed up the output of parts. The company makes the vertical honing equipment in The production of standardized fixtures reduces the part preparation process and improves the preparation efficiency. preparation process and improve preparation efficiency. Table column with standardized series of fixtures.

Standardization of tools

The tools used in the honing process are composed of a system of connections, and the use of standardized Standardized interface of tools can be achieved by replacing the minimum number of tools when changing the machined parts. The purpose of changeover can be achieved by changing the minimum number of tools. The use of standardized tools can ensure the reliability and stability of tool clamping and ensure the stability of machining. The use of standardized tools ensures the reliability and stability of tool clamping and the stability and consistency of machining.

Continuous improvement

Honing process produces non-conforming products, which is a great waste and not in line with lean thinking, and should be improved in time. The processing of the generated non-conforming products will take up a lot of resources, and the use of these resources is not at all beneficial for creating economic benefits. At the same time, with the development of processing technology, new honing tools and materials are constantly developed, which will also promote the processing of parts by a certain role, to be applied in a timely manner, continuous improvement, to promote the quality and yield.

On-the-job training, the cultivation of multi-skilled workers

Cultivate multi-skilled workers, especially those who operate honing equipment, must master several skills of part clamping, fixture replacement, tool installation, program setting, sample part debugging and part inspection. According to the characteristics of honing processing, several people in this team were selected as the training target, and after the training period, several people reached the expected training target.
Operators who have reached the operation requirements can be considered as qualified to operate honing equipment, and can be intentionally arranged to produce in honing processing positions and to rotate positions, which is conducive to improving the working mood and enthusiasm of operators, so that operators do not feel fatigue mentally and physically, and improving interpersonal relationship and increasing knowledge reserve through such a transfer, which is conducive to improving the sense of responsibility of operators.

Change of operation method

The company generally adopts the fixed staffing system in the allocation of operators, that is, for a certain equipment, even if the output is reduced, the same number of operators will be equipped to operate these equipments. However, the characteristics of aviation products are many varieties and few batches, and the changes of production volume are more frequent. Therefore, whether the production volume increases or decreases, it is important to deploy operators according to the amount of production volume. Lean production is this kind of thinking, breaking the original staffing system, reducing operators when the production volume decreases, and increasing operators when the production volume increases.

Concluding remarks

Lean production integrates the advantages of mass production and single-piece production, implements pull-type just-in-time production, is people-oriented, fully mobilizes the enthusiasm of personnel, gives full play to the subjective initiative of personnel, cultivates multi-talented, continuously improves work skills, effectively allocates enterprise production resources, and reduces enterprise production costs. Less input, more output is the superiority of the lean production method, to improve the value-added labor, eliminate useless labor and reduce waste. After carefully implementing the above measures, the processing efficiency, processing stability, product quality and equipment capacity of honing processing have been significantly improved, and the equipment has been restored from the original bottleneck to become a positive production demand equipment. The success of trying and studying the lean production method of honing processing production is mainly based on the following experiences.

• (1) Fully analyzed the characteristics and features of honing production, carried out targeted process improvement and production preparation guarantee, laid the foundation for stable output of parts, and continuously carried out activities to improve quality and efficiency, and continuously optimized the processing quality and efficiency of honing processing.
• (2) Deeply implement the main idea of lean production, reduce production costs from various aspects, eliminate waste, improve efficiency, and pull the smooth output of parts.
• (3)Cultivate employees to be multi-talented, give full play to their subjective initiative, improve their enthusiasm and motivation, and let them master their skills and take the initiative to bring their creativity into play.
• (4) The use of effective management tools such as Kanban makes the logistics and information flow of production operations fully coincide, improving the management and control capabilities of the operation site.

Author: Sun Dawei

Source: China Flange Manufacturer – Yaang Pipe Industry (www.epowermetals.com)

(Yaang Pipe Industry is a leading manufacturer and supplier of nickel alloy and stainless steel products, including Super Duplex Stainless Steel Flanges, Stainless Steel Flanges, Stainless Steel Pipe Fittings, Stainless Steel Pipe. Yaang products are widely used in Shipbuilding, Nuclear power, Marine engineering, Petroleum, Chemical, Mining, Sewage treatment, Natural gas and Pressure vessels and other industries.)

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Reference:

• [1] Wang Shiqing, Deep Hole Machining Technology [M]. Xi’an: Northwestern Polytechnic University Press, 2003. [2] Liu Shuhua, Real Lean Production [M]. Beijing: Machinery Industry Press, 2010.
• [3] Zhang Wu, modern industrial enterprise management [M]. Beijing: Beijing Institute of Technology Press, 2011.