Lean manufacturing waste in production. Classification of the main types of losses at industrial enterprises

Enterprise management, which allows you to eliminate losses that do not add value to the products.

Losses are commonly called “muda,” which literally means futility in Japanese. It is customary to distinguish 7 types of losses in lean manufacturing. These include costs associated with:

• Overproduction;
• Inventories;
• Over-processing;
• Extra movements;
• Release of defective products;
• Time expectations;
• Transportation.

What are lean waste?

Overproduction is expressed in the production of excess products. This applies to both volumes and production time, that is, when the enterprise has produced a lot of product that will not be sold immediately. In turn, inventory losses occur when more raw materials and semi-finished products enter the production process than needed. When we talk about overprocessing, we are talking about effort that does not add value to the final product for the consumer client.

In production, there is often unnecessary movement associated with the movement of workers or tools, as well as equipment used during the production process, which does not contribute to increasing the value of the product from the point of view of the buyer. Losses can occur as a result of the release of low-quality products that require additional steps to check, sort, and, if necessary, dispose of, replace, or repair.

Expectations in the form of interruptions in the work process, which are associated with waiting for people, some materials, equipment, or waiting for the necessary information, can also cause production losses. In turn, the peculiarities of transportation and the movement of materials within the enterprise can cause costs that are completely unnecessary for the end consumer.

All of the listed categories are the main losses of lean production, and it is to eliminate them that the introduction of a well-developed management approach to organizing the most efficient operation of the enterprise is aimed.

It should be noted that with a more qualitative approach when implementing a system, 8 losses of lean production are often identified. Experts consider unrealized human potential to be the eighth type of cost. Often employees are able to offer many useful ideas. Failure to use such ideas is the reason for the loss of the most valuable thing - the potential of people working in a particular production.

Sources of waste in lean manufacturing

The main seven types of waste in lean manufacturing are generated for the purpose of overload and unevenness. They are the sources of unnecessary costs that do not add value to the product.

Mura - definition of uneven performance of work. Examples of unevenness include:

• Fluctuating work schedule, which is not associated with changes in demand, demand for products by the end consumer;
• Uneven operating mode, related to operations being performed at first at too fast a pace, and then resulting in downtime-waiting.

Muri is the definition of equipment overload or operator overload. This occurs when working at too high a speed, using too much effort over an extended period of time compared to the workload required by the project or work standards.

Muri, like mura, are sources of losses that are eliminated through proper training. As a result of their elimination, it is possible to complete the task of reducing various losses that do not add value to the final product.

Articles on the topic "Lean Manufacturing":

Taiichi Ohno (1912-1990), CEO of Toyota, once established 8 types of muda. It is quite possible that there are other types of muda, but the key 8 are worthy of special attention:

• 1. Overproduction (excess production);
• 2. Transportation;
• 3. Waiting;
• 4. Inventories;
• 5. Defects;
• 6. Overprocessing;
• 7. Movement;
• 8. Loss of creative potential;

Overproduction is considered one of the most terrible types of losses, because other types of losses depend on it.

In order to eliminate this type of loss, you just need to avoid producing unnecessary things. It is necessary to produce only what was ordered by the buyer.

In addition, large batches may cause overproduction, which may result in a lack of rapid changeover capabilities. Anticipatory production can also become one of the reasons for overproduction.

Excessive equipment, non-standardized and unsystematized quality can also be reasons for overproduction.

Overproduction causes certain consequences - raw materials are consumed prematurely, resulting from the purchase of materials, which leads to an increase in inventories to excess levels, and loss of quality.

Overproduction can be avoided using a pull supply system, as well as by leveling the load on production lines.

Long readjustment - as a consequence of producing products in large quantities, can also be the cause of excess inventories. In addition, the production planning and material supply system may also be imperfect.

There is a need for additional space, warehouses, labor, because... reserves are being built up.

All these excess inventories hang like a dead weight in the enterprise budget system.

Sources of losses:

• · special warehouses for materials and products for
• · ensuring timely deliveries that hide production problems and do not add value to the customer;
• · materials and semi-finished products paid for by the company, but at the delivery stage.

Areas of improvement:

• · analysis of the demand for products with a long shelf life;
• · analysis of the timeliness of price changes for illiquid inventories, analysis of complaints for illiquid inventories;
• · balancing production and sales;
• · analysis of inventory dynamics and reduction of inventories of materials and raw materials between operations.

A value stream map can help identify inefficiencies in the production flow organization. By displaying material flows and their direction, we see the distance that a workpiece or material travels before it becomes a finished product. Increased transportation costs lead to higher prices for products.

Optimizing the location of equipment, storage facilities, and the direction of material flows in general helps reduce the number of transportations.

“Movement” refers to the movements of working personnel during a shift. These movements can lead to an increase in injuries, a decrease in staff productivity, and the accumulation of fatigue.

It is worth noting that the personal role of the worker is very important in the process of optimizing his work shift and the actions he performs. The way to solve the problems of optimizing the production process can be considered to be advanced training and effective organization of the workplace. This personal involvement of workers can be carried out within the framework of Kaizen - a movement - constant small improvements that occur gradually and on their own.

By comparing all types of losses, you can identify the loss with the least damage - “Waiting”.

This is the time during which no useful action is carried out, no value creation occurs.

Waiting is a unique type of loss, into the stage of which it is necessary to transfer all other losses that cannot be eliminated. To measure expectation, it is necessary to calculate the total number of equipment and personnel downtime per shift, month, quarter, year. This can be done by timing the work of personnel and equipment.

Ways to improve:

• · production planning based on orders;
• · suspension of the production process in the absence of specific orders;
• · creating a flexible schedule for both workers and equipment;
• · implementation of 5S (workplace organization system);
• · implementation of TPM (a system of total equipment maintenance, with the involvement of all personnel in it);
• · implementation of SMED (quick changeover);
• · implementation of Kaizen (small step changes on an ongoing basis);

All of the above measures help reduce waiting times.

In addition, excessive processing of products, the reason for which is the lack of a certain production standard by the worker, also contributes to an increase in costs.

Before starting to fulfill an order, the employee must have a clear understanding of what he is producing, what actions add value to the product, and what final properties this product should have. This all needs to be standardized.

Another type of loss - defects in manufacturing - may entail costs for adjustments and modifications, corrections, further control, and reorganization of the workplace to eliminate these defects. These losses arise due to technology violations, low qualifications of workers, incorrectly selected equipment or materials. The cost of defects can be calculated by summing up the total amount of defective items and rework costs. As elsewhere, the interest and involvement of each employee to produce high-quality goods is very important here.

And the last type of loss is loss of creative potential.

Sources of losses:

• · incorrect attitude towards employees, focused on them performing only mechanical work;
• · uncomfortable working conditions and, as a result, the desire to leave the workplace as quickly as possible;
• · undeveloped system of incentives, rewards for successful work, motivation;

Areas of improvement:

• · availability of explanations of the goals and objectives of the enterprise for each employee;
• · involvement of each employee in a system of continuous stepwise improvements (Kaizen);
• · creation of more comfortable working conditions;
• · creation of a new employee motivation system or high-quality improvement of the old one;
• · maintaining open contact between personnel and the management team of the enterprise.

From the point of view of lean manufacturing, the entire functionality of the enterprise is divided into processes that accumulate costs, losses that do not add value to the end consumer, and processes that add this value to the product for the consumer. The main goal of lean manufacturing is to reduce these aforementioned processes that do not create value for the consumer.

Lean Manufacturing Tools:

• · Continuous improvement - Kaizen;
• · Organization of workplaces - 5S;
• · Standard operating procedures;
• · Total productive service;
• · equipment (Total Productive Maintenance -TPM);
• · Just-In-Time - JIT;
• · Maps of the movement of material assets;
• · Kanban;
• · Fast changeover;
• · Built-in quality.

The use of these tools clearly increases the competitiveness of the organization, creating value for the consumer. Value creation is marked by the creation of a value stream.

A value stream is a compilation of all actions, processes, etc., that are performed in order for a product to go through three stages of management: problem solving from the development of the product itself to its release, managing information flows from accepting an order to planning the delivery schedule of goods, transformation of a product in a physical sense (from raw materials to a finished product).

The next step in putting lean manufacturing concepts into practice is to identify the entire value stream for each product. It is rarely included in the process, but almost always shows the muda value.

Lean manufacturing is about eliminating waste. What does the word “loss” mean? The article will help you understand the types of losses, show examples in life around you, and also teach you how to count the money that a company loses because of them. It is offered to help you ( required for downloading).

Most of the material on this topic presented in books describes in detail losses in production processes. Therefore, we would like to talk about losses, first of all, in office processes, in service delivery processes - where we encounter them every day.

First, let's define the wording.– these are any actions that are carried out in the process of manufacturing a product or providing a service, consume resources, but do not create value for the client. Those. actions that you can do without.

Currently, Lean Manufacturing is divided into: eight types of losses.

EXPECTATION

The most common type of loss in office activities isexpectation . We all know that if you need to agree on an agreement in several departments, you will have to wait a long time. Employees usually take their time. Each department, having received the document, to begin with... will simply put it aside... after all, no one is going to abandon their work, which is already in the process of being completed, and immediately begin reviewing a new document. Therefore, the contract will first lie for a day or two, and then it will be reviewed. As soon as the case is transferred to the next department, everything repeats itself...

Moreover, each of the department’s employees is sincerely confident that he is working as efficiently as possible. And indeed everyone is constantly busy analyzing some document. But no one pays attention to the fact that in our approval process, the contract lies there for several days, waiting and nothing happens to it... Imagine, if we remove all expectations, how quickly we could receive the necessary documents, services... How far we could overtake your competitors!

A visit to any government institution is also not complete without this type of loss. And it doesn’t matter whether we have a queue with a time stamp or not, we still face a wait. First we wait in line at the reception to receive a card and coupon, then in front of the doctor’s office. I repeat, it is quite possible that at this moment all employees are working and very busy, but we, as clients, are forced to wait and waste our time. And, of course, we are not ready to pay our money for this wait.

From practice: in office processes, losses from waiting reach 60-80% of the time of the entire process. That is, if we conclude an agreement for 10 days, then for 6 days the agreement lies on the tables. Do you think the client is willing to pay for this?

And in our everyday life, any queue, be it at a store checkout, at a gas station, or a frozen computer, is all a waste of our time.

Calculation: Let's take a very average employee salary of 24 thousand rubles, with an average working hours per month of 160, we get the cost of 1 employee man-hour at 150 rubles.

Employees received an invitation to a meeting. , i.e. Sorry - it’s delayed 🙂, for half an hour. Everyone is waiting for him to appear.

Direct losses from expectation:

This is the cost of waiting at the door for just one meeting. How many such meetings per month, year? and maybe some directors consider it bad manners to arrive on time...

The presence of losses in the process leads not only to monetary losses (the so-calleddirect losses), but also to indirect losses- which cannot be assessed in rubles, but which affect the company’s image, customer loyalty, competitive advantage:

Sequencing	The time when the contract lies and awaits processing	Time of processing
The client submitted the contract for approval to the department		1 min
The contract lies on the table and waits until the boss is free	3 hours
The head of the department identified the performer		1 min
The contract lies on the table and waits for the contractor to complete previously started work.	3 hours
The contractor prepares a conclusion and submits the decision to the boss for approval		2 hours
The contract lies on the table and waits until the manager is free	3 hours
The manager endorses the conclusion and informs the client		5 minutes
Total	9 o'clock	2 hours 7 min
Total process duration	11 hours 7 minutes

Please note: only 2 hours out of 11 pass with the document real work, and that's all 18% of total duration. The rest of the time the papers lie “stupidly” and wait. And the client is waiting too...

How many more clients do you think the company would have if the conclusions always done in 2 hours?

There are two key words in the question I asked: first - ALWAYS - means the same duration for each performance, and second - 2 hours — this is the minimum time it takes to complete a process without wasting time waiting.

So how? Is it possible to implement a process without waiting for the client?

DEFECTS

The following types of losses are quite difficult to observe in the office, but in fact they are very common -defects are the manufacture of a product or the provision of a service with errors, requiring additional resources to correct them . Defects always entail additional processing, which only increases the cost of production and lengthens the process time. After all, it takes less time to do everything correctly the first time than to first do it with an error and then redo it.

In production, fixing defects is simpler: the master sent 10 workpieces to the machine in the morning, and in the evening received 9 processed ones and 1 defective one that was not accepted by the controller. And in the office everything is more hidden from prying eyes: an employee sits, looks at the computer, what is he doing there? It can be difficult to understand. When providing services, a client can usually see and notice an error only at the final stage. But how many errors were identified and corrected during execution by the performers themselves - usually this is not even recorded. Employees themselves are not interested in informing management about their “shoals”, it’s easier to redo it quietly.

From practice: The bank uses the services of an insurance company to obtain insurance for non-real estate when concluding mortgage agreements. Bank employees constantly complain among themselves about the high level of defective documents from the insurance company. Management does not respond to complaints because there is no documentary evidence. After collecting and recording data on changes in insurance policies for a month, we Errors were identified in 95% of documents. For the bank (as well as for the insurance company) this is a huge loss of resources: after all, all documents had to be redone, agreed upon with clients, and often with the registration chamber, which, of course, affected the time of issuing a loan and the cost of the operation for the bank. Realizing the terrible statistics, the bank's managers set strict conditions for the insurance company's managers about the need in more than 5% of cases.

Here are examples from real life: errors when placing price tags on goods in a store (provided that this was not done on purpose), as well as the loss of test results or an outpatient card in a clinic.

Calculation:

Parameter for calculation	Meaning
Number of insurance policies (= number of mortgages), per year	10 000
Bank employee time spent on identifying errors and “pushing” the insurance company	10 minutes = 0.17 hours
Waiting time for the bank and the client - while the insurance company remakes the policy	0.5 days
Time to prepare (remake) 1 insurance policy by the insurance company	10 minutes
Cost of additional materials (valuable form, cartridge....) for 1 insurance policy	20 rubles
Cost of 1 person-hour of a bank employee	150 rub.
Calculation	10,000 pcs* 0.17 hours* 150 RUR
Total bank losses	255,000 rubles per year
Total loss insurance payment for alterations to employees	255,000 rubles per year
Total insurance losses for additional materials	200,000 rubles per year
Additional time lost from waiting for the client	0.5 days

OVER-PROCESSING

The next type of loss isunnecessary processing - performing operations that are not necessary for the client, which as a result lead to a delay in the entire process , and also, often, further bureaucratizes the process.

For example: in large companies, when signing an agreement, in addition to direct executors in the economic, legal departments and accounting, a visa is also required for the head of this department. Everyone understands that this is a requirement, but traditions require it... and each additional visa is both the time it takes for the documents to “sit” on the table and the cost of the manager’s working time.

Or another real experience: every day the office collects documents on clients’ transactions for the day and puts them in a certain order - this takes 15-20 minutes, i.e. per month about 8 hours or a whole working day. Completed documents are sent to the accounting department. Imagine our surprise when we found out that the accounting department, having received beautifully folded pieces of paper, pours everything onto the table in one big pile and sorts it according to a completely different principle!

Another example: this is duplication of information, contracts in electronic and
in paper form, and sometimes also scanned - just in case. We spend and we pay employees for time for actions that the client does not need and which only complicate our processes.

Calculation: The price of a formal signature: the prepared contract for the provision of bank services was signed first by the executor, then formally by the head of the office.

Parameter for calculation	Meaning
Number of contracts, per year	6 000
Manager's time spent on approval of 1 contract	1 minute = 0.017 hours
Client waiting time - until the manager is free

Lean Production ideologist Taiichi Ohno identified seven types of losses in mass production, without identifying which it is impossible to improve the efficiency of any enterprise:

• - overproduction;
• - expectation;
• - movements (unnecessary movements of personnel, tools);
• - transportation;
• - excessive processing;
• - reserves (materials, resources);
• - defects and alterations.

Overproduction - producing ahead of what is actually required by the next production stage or customer. The worst form of loss, which amplifies the other six.

Overproduction losses occur when a business produces, assembles, or releases more than is needed. Some things are done just “just in case,” not “just in time.” Lack of planning, large backlogs, long changeover times, insufficient contact with customers (lack of understanding of their constantly changing requirements) lead to longer production cycles. The manufacturer unreasonably believes that its customers need more product, and as a result suffers from the costs of producing goods and services that cannot be sold.

What to do?

Identify processes during which more is produced than the customer “pulls”, and which require additional measures to organize the storage of excess products between operations.

Reduce losses by reducing the amount of time spent setting up, retooling and balancing production lines.

Waiting - downtime of operators during operation of machines due to equipment malfunction, late receipt of necessary parts, etc.

Waiting time occurs when people, operations, or partially finished products are forced to wait for further actions, information, or materials. Poor planning, unnecessary suppliers, communication problems and poor inventory management lead to downtime, which results in lost time and money.

What to do?

Identify people or equipment that are waiting for the completion of the previous or the beginning of the next operation, the receipt of materials or information.

Reduce waste by leveling production lines using a cycle time/takt time bar chart to synchronize processes. Movement - movements performed by operators that go beyond the scope of productive work or that are not necessary, for example, searching for parts, tools, documentation.

Movement waste is the unnecessary movement of personnel, products, materials and equipment that does not add value to the process. Often workers make unnecessary trips from their site to the workshop warehouse and back, as well as around equipment they do not need. This is one of the most unpleasant losses for both ordinary personnel and management, since wasted time and downtime reduce the efficiency of production processes, making the work of workers more difficult. Although most manufacturing processes are designed from the outset to minimize unnecessary movement, movement waste remains a major source of waste, occurring unnoticed and leading to failures.

What to do? Identify when personnel are making unnecessary movements or movements and create a comprehensive diagram of the actual process flows. Reduce waste by developing and studying a value stream map and/or physical flow map for each process and subsequently reducing the movement of operators, equipment, and materials.

Transportation is the movement of parts and products unnecessarily, for example, from some stage of production to a warehouse rather than to the next stage.

Transport waste occurs when personnel, equipment, products or information are moved more frequently or over greater distances than is actually necessary. In multi-step processes, materials and personnel move from process to process that are separated by space and/or time. Instead of placing processes sequentially or side by side, they are often located far apart, requiring the use of forklifts, conveyors or other transport devices to move materials to the next operation. All these movements do not add consumer value to the product being manufactured.

What to do? Identify movements of personnel, materials, or information that do not contribute to the value creation process. Reduce wastage by minimizing the physical distance of materials and vehicle movements by identifying zones and applying redesign. Over-machining is the implementation of unnecessary or incorrect machining, usually due to poor quality tooling or poor product design.

Losses from excessive processing occur when producing products or services with higher consumer qualities than are required by the buyer and for which he is willing to pay. Adding functionality that has no value in the eyes of the customer does not improve the product or process. Lack of information about how customers use products or services often encourages them to add unnecessary functionality that the manufacturer thinks customers need or want (even though this is not known for sure).

What to do? Find products returned by customers as broken or defective in areas where no signs of wear were visible prior to the breakdown. Clarify the situation through a consumer survey and research on the product’s performance in real conditions.

Reduce waste by determining what functionality the customer actually needs and what they are willing to pay for. To do this, you need to have a good understanding and a clear idea of ​​exactly how and under what conditions customers use the product produced by the enterprise. Inventory - holding more inventory than is necessary for the accurately planned operation of the pull system.

Physical inventories are typically classified by their position in the value stream and their intended purpose. To describe the position of inventories in the production process, concepts such as raw materials, work in progress and finished goods are used. To describe the intended purpose of inventories, the concepts of buffer stock, safety stock and shipping stock are used.

Since inventories are always characterized by a specific location and purpose (and some inventories perform several functions at once), the same items can simultaneously represent, for example, finished goods and buffer stock. Similarly, the same products can be both raw materials and safety stock. And some items may even be finished goods, buffer stock, and safety stock (particularly if the value stream between raw materials and finished goods is not very long).

To avoid misunderstandings, it is important to accurately define each type of inventory. Raw Materials

Products in the plant that have not yet been processed.

Work in Process (Work-in-Process) Products located in the enterprise between stages of processing. In Lean manufacturing systems, standard work in process is the minimum number of parts (including those on machines) needed to keep a cell or process running smoothly.

Finished Goods Products whose production has been completed and are ready for shipment.

Buffer Stock

Products that are typically stored downstream - at the end of a production line or process in order to meet customer needs in the event of a sudden short-term increase in demand beyond current production capacity.

Safety Stock

Products located anywhere (raw materials, work in progress or finished products) and insuring subsequent stages from possible problems at previous stages of production. Safety stock may also be called emergency stock.

The terms buffer stock and safety stock are often used interchangeably, leading to confusion. There is an important difference between the two, which can be summarized as follows: a buffer stock protects a business's customer in the event of a sudden change in demand; Safety stock protects the enterprise itself from the temporary inability of its production stages and its suppliers to meet demand.

Shipping Stock

Products in the shipping areas of a production line, ready for the next shipment. As a rule, their volume is proportional to batch sizes and shipping frequency. Another name is cycle reserves.

Losses due to excess inventory are associated with a variety of quality problems such as rework and defects, problems in labor and/or production scheduling, overestimation of lead times, and problems with suppliers. It is too expensive to maintain excess inventory, which freezes capital and requires bank interest payments. Excess inventory reduces the return on investment in labor and raw materials.

What to do?

Identify excess production capacity, excess inventories of raw materials, work in progress or finished goods with a turnover of less than 10 times per year.

Reduce waste by applying just-in-time and kanban techniques.

Correction - inspection, rework and scrap.

Losses due to defects or the need for rework occur when there is no reliable preventive system, including poka-yoke methods, and built-in error protection. Every time a manufacturer makes a mistake while working with a product and passes it on to the next step in the process or, worse, to the buyer, the manufacturer is forced to accept rework as an integral part of the process. He loses money twice every time he produces, assembles, or repairs something with errors, while the customer only pays once for the product or service.

What to do?

Identify defective or unfinished products or services, as well as finished products that are being reworked or have to be discarded. Reduce waste by improving visual inspection systems and developing more comprehensive standard operating procedures.

Implement a built-in poka-eke error protection system where the source of errors is hidden.

Identifying and reducing the losses discussed above will give a significant impetus to the company’s recovery from the crisis and/or the development of production and the development of new products by freeing up the enterprise’s resources.

Losses	Causes	Consequences	How to calculate losses?	How to fix it?
Overproduction	· large parties; · impossibility of quick changeover; · anticipatory production; · redundant equipment, unstable quality.	· premature consumption of raw materials; · procurement of materials; Excess inventory, loss of quality.	· The amount of unclaimed products and supplies in warehouses and intermediate operations. Over the course of a month, a quarter, a year.	· pull supply system; · leveling the load on production lines.
Excess stocks	· long readjustment; · production of products in large quantities; · imperfection of the production planning and supply of materials system.	· increase in area; · additional labor; · the need to search; Possibility of damage; · the need for additional pallets.	· Determine how many materials are in the warehouse that are not needed in the next week (month - depending on the supply cycle)	· pull production system; · production leveling; · reduction in batch size; · improvement of the planning system.
Transportation	· irrational placement of equipment; · large distance between production sites; · inefficiently organized production flow; · remoteness of storage facilities.	· increased transportation costs; · additional search costs; · Damage to products during transportation.	· The cost of moving workpieces from one operation to another, and in the warehouse. Possible defect due to improper transportation. Value stream map.	· optimization of equipment location; · optimization of production areas; · optimization of warehouse locations.
Movements	· irrational organization of work space; · irrational arrangement of equipment and containers; · non-coordination of operations; · lack of standardized processes.	· decrease in labor productivity; · staff fatigue; · increase in injuries and occupational diseases.	· Timing of worker movements, determining time and distance. Spaghetti diagram.	· optimization of the production process; · staff development; · optimization of equipment distribution; · efficiently organized workplaces.
Expectation	· imbalance of production processes; · imperfect planning; · production of products in large quantities.	· increase in time for manufacturing a unit of product; · decreased productivity; · staff demotivation.	· Timing of work of personnel and equipment. Total downtime per shift, month, year.	· alignment of production processes; · optimization of equipment location; · reduction of changeover time.
Overprocessing	· lack of standard; · lack of understanding of what the consumer wants; · imperfection of technology.	· increase in production costs; · increase in time for production of products.	· Find out from the customer which properties of the product he considers necessary, and which are secondary, or not needed at all. Over-processing costs.	· standardization; · careful study of consumer requirements.
Defects rework	· violation of technology; · low qualifications of the employee; · inappropriate tools, equipment, materials.	· additional costs arise: for revision, for control; to organize a place to eliminate defects	· The quantity of defects - its cost, or the cost of rework.	· organizing the process of ensuring the release of quality products; · implementation of a system for efficient operation of equipment.

Bibliography:

· Womack James P., Jones Daniel T. - Lean Manufacturing: How to Eliminate Waste and Make Your Company Prosper/Trans. from English – M.: Alpina Business Books, 2004. – 473 p. – (Series “Management Models of Leading Corporations”).

· Mann, David - Lean management of lean manufacturing/ D. Mann; lane from English [A. N. Sterlyazhnikova]. Transl.:.- New York: Productivity press, cop. 2005 Moscow: Standards and quality, 2009

· Rampersad, Hubert K. - TPS-Lean Six Sigma: a new approach to creating a highly effective company: per. from English / H. Rampersad, A. El-Homsi. Per.:.- Charlotte, N.C.: Inform. age publ., 2007 Moscow: Standards and quality, 2009

· Taiichi Ono. - Toyota production system: moving away from mass production- M: Publishing House ICSI, 2012. ISBN 978-5-903148-39-4

· Just in time for workers. - Productivity Press development team. M. Publishing house ICSI, 2007, ISBN 5-903148-02-6

1. Poka-yoke– preventing errors, constructing a process in a way that prevents the transfer of a defective product to the next stage of production.

2. Losses
Enterprise losses is any activity that consumes resources but does not create value for the consumer. Losses are divided into seven types:

1. Overproduction.
2. Marriage and alteration.
3. Movement.
4. Movement of materials.
5. Backlogs at the “process stages”.
6. Additional processing.
7. Downtime.

1. Losses overproduction occur when workshops or areas produce, assemble or release more than necessary. Imperfect work of the planning and dispatch department, large backlogs, long readjustments, absence or insufficient contact with the client lead to a wasteful increase in the duration of business processes.

Example. Shop No. 202 smelted 410 cases per shift, although the next in the production chain, Shop No. 203, is capable of processing only 250 cases per shift. Extra resources have been spent, the question is “for what?”

2. Defects and alterations. Every time we make a defect and pass it on to the next stage of production, we lose money twice when we try to fix it, while the customer only pays us once. It’s even worse if the defect went to the customer. After receiving back a defective product, we may lose the customer. Not everyone will want to purchase goods from a defector for the second time.

Example. The plant produced a new DPT 810-2U1 engine in a batch of 100 pieces and a cost of 800 thousand rubles. 60 engines were returned for warranty repairs. Additional costs amounted to 400 thousand rubles. for the engine. The sales price of DPT 810 is 1,050 thousand rubles. Total: sales revenue – 105 million rubles. Planned income – 25 million rubles. (prior to return for warranty repair). Including repairs - only 1 million rubles. "Excellent result!

3. Movement. Absolutely unjustified movements (of employees, equipment, raw materials) that lengthen the business process.

Example. Due to construction problems (the workshop has just been built), 480 employees of workshop No. 5 are forced to visit a special facility 370 meters from the workshop building. The average salary of an employee is 18 thousand rubles. With an average worker speed of 5 km/h, visiting this establishment will require about 8 minutes of working time – about 192 people/hour per day or about 20 thousand rubles. only in terms of wages, and about 440 thousand rubles per month.

4. Movement of materials. Often, instead of a sequential arrangement of business processes, one has to deal with the use of technical means - cranes, loaders, vehicles, conveyors, etc. to move workpieces to the next processing stage.

Example. After mechanical processing in workshop No. 33, the product is stored in boxes and returned for heat treatment to workshop No. 30, from where it travels back to workshop No. 33 for assembly.

5. Backlogs at the “processing stages”. Most businesses use borrowed money to replenish working capital. But having inflated inter-operational inventories of raw materials is an unaffordable luxury for a prudent manager. About 30% of the purchasing reserve can easily be found in excess inventory.

Example. During an unscheduled inventory of the hardware site, about 280 thousand bolts were identified, while only 70 thousand pieces were needed to complete the planned task for the month. So, with a bolt price of 27 rubles. per piece, 5670 thousand rubles. working capital is “buried in the ground.”

6. Additional processing. Production of products or services with consumer qualities that significantly exceed the consumer's needs, for which he agrees to pay. Ignorance or misunderstanding of the process of using a manufactured product leads to unnecessary processing operations.

Example. The processed surface of the side and rear parts of the part on a longitudinal grinding machine will please the eye of mechanics only during a major overhaul of the product in 10-12 years. Today's processing losses are enormous—millions a year.

7. Downtime. They mainly arise when there are unfinished products, when enterprise employees stand and wait until they can start working. Such downtime is the result of incompetent planning, weak management, unprofessional inventory management and lack of basic interaction between departments.

Example. In the assembly shop, about a dozen workpieces had accumulated near the milling machine; the operator could not install them on the machine due to a broken gantry crane. Considering that this machine is at the beginning of the technological chain, the work of the workshop has stopped. The search for a repairman was crowned with success after 1 hour and 20 minutes - the crane started working. Approximate losses: 76 machine operators were idle for 80 minutes (with an average salary of 18 thousand rubles per month - this is 10.4 thousand rubles in losses only in workers’ salaries, not counting the fact that they will have to take people out on weekends, and others The workshops were also idle due to a lack of workpieces).

Of all types of losses, the most dangerous is overproduction– producing more items faster or earlier than required for the next production stage, since it creates and simultaneously hides other losses. In an economic sense, overproduction leads to an increase in the volume of working capital frozen in work in progress, an increase in the tax base, an increase in the costs of purchased materials, an increase in the volume of finished products, etc. Other associated losses also arise, for example, defects are hidden in large volumes, which will be discovered, perhaps after some time, and, therefore, it will be very difficult to restore the conditions for their occurrence, identify and eliminate their causes.

Overproduction leads to inventories, which not only affect working capital, but also form a whole chain of additional costs, such as: additional accounting and reporting functions, over-documentation, the need for production and warehouse space, a multiple increase in the volume of lifting, transport and warehouse operations.
Overproduction (and not only that) also entails expectations, and, therefore, loss of labor productivity (output), as well as a decrease in the equipment utilization rate.

Internship

Description of the situation. At the enterprise, whose scope of activity is the production of switch products for railway transport, the concept of lean production is being introduced, but there is a steady tendency to freeze working capital.

A way to identify problems. In 2011, experts from Krona Group JSC conducted a survey of the enterprise in order to identify problems in the production system and develop proposals for improving the situation.

To achieve the goal, the following tasks were set:

Related information.