Operative scheduling in unit production. Operational and production planning in unit production

Single production is characterized big amount orders for the manufacture of a variety of products in units and less often in small, non-repetitive batches. At the same time, casting works predominate in some products, blacksmithing in others, mechanical work in others, etc. Therefore, operational planning / should group orders for launch in such a way as to ensure the best combination of order production times with uniform loading of the main workshops.

This essential condition should be taken into account when drawing up the calendar production program for unit production for each month of the planning period. In order to meet such a condition, at many enterprises, when receiving an order from a customer and concluding an agreement with him, before specifying the deadline for completing the order, they make a preliminary calculation of the production cycle for manufacturing the order. next distinctive feature unit production planning is the inclusion in the order manufacturing cycle of all stages of preparation for production and manufacture of the product, namely: development of the design of the product (if the product does not have ready technical documentation from the customer), development of the manufacturing technology of the product, standardization of labor costs, design and manufacture of the necessary equipment, manufacturing, testing and fine-tuning of the product. IN single production operational management is carried out according to a custom system (Table 37), in which the planned unit is an order for a product, and for complex multi-piece products, an assembly connection.

Operational planning in unit production includes: calculation of the production cycle of order fulfillment and construction of a volume-calendar schedule for the fulfillment of individual orders and a summary for all orders; calculation of calendar deadlines for advances in the work of shops; calculation of loading of equipment and production areas in the planning period; daily account of the fulfillment of orders.

The calculation of the production cycle for each order begins with the distribution of the labor intensity of the order by type of work and the calculation of the required number of jobs CPM (equipment)

where m, - the complexity of this type of work on order;

Fdo - the actual fund of the operating time of the equipment.

On the basis of such calculations and taking into account the possible interoperational aging of parts, a volume-calendar schedule for order fulfillment is formed for each order (Fig.).

The graph is built in reverse order technological process starting from the test or assembly shop. According to the schedule, the general cycle of manufacturing an order is determined, which is compared with a given period. For orders with a short production cycle (less than a month) and a small number of executing shops (one, two), the volume schedule is not drawn up.

Rice. 1 Volume-calendar schedule order fulfillment

Rice. 2 Consolidated volume-calendar schedule of order fulfillment

The calculation of calendar lead times in the work of workshops is necessary for their coordinated uninterrupted operation and for all the parts included in this product to arrive at the assembly by the specified date. Therefore, parts that have a longer production cycle are put into production earlier than other parts.

A consolidated volume-calendar schedule for the fulfillment of all orders is necessary for the mutual coordination of work on orders in time and for a more complete use of equipment and space (Fig. 2). When constructing a consolidated volume-calendar schedule, it may happen that the deadlines for completing the same work on different orders on the same equipment coincide, and it turns out to be overloaded, or the deadlines for completing work on one order and starting work on another on the same equipment do not coincide, and this equipment is underloaded. In both cases, it is necessary to adjust the deadlines for the execution of work provided for by the schedules for the implementation of individual orders. At the same time, it is necessary to determine measures to eliminate bottlenecks and reload underloaded equipment. In order for the consolidated volume-calendar schedule to meet the above requirements, the PDO and PDB of the main workshops calculate the loading of equipment and the use of production areas, finding the best option for using the available capacities.

The consolidated volume-calendar schedule is adjusted monthly, taking into account data on the implementation of the monthly program by the main workshops, on the status of work in progress on orders, on new assignments from the ministry and orders accepted by the enterprise. At the same time, the nomenclature and scope of work for previously included orders are being specified. Taking into account these features, the consolidated volume-calendar schedule of orders is finally specified and, on the basis of it, the PDO issues a monthly production work program to each workshop, which indicates the scope of work for each order and the timing of their implementation (form 8).

The planning and dispatching office of the main workshop, having received a monthly production program from the PDO, distributes the work provided for in it among the production sites, makes volumetric calculations for the correct use of capacities and the elimination of disproportions in loading the equipment of the sites. Sometimes, in addition to the monthly program, the PDB of the shop, before the start of the planning period, gives the foremen updated schedules for the distribution of work for shorter planning periods (decade, week). When determining the timing of the launch and execution of individual works, they are guided by the duration of cycles, current needs and the state of work in progress. The fulfillment of monthly tasks (schedules) must be fully provided with sets of working drawings and other technical documentation, materials, blanks, semi-finished products, parts, tools, production documentation, etc. The basis of planning and distribution work for a shift is a shift-daily plan, in which tasks are specified for each day and shift for each worker. The reality of shift assignments must be ensured by advance and thorough operational preparation of production. Shift tasks include only such works for which technological documentation, tooling, materials and workpieces have been prepared.

Rice. 3 Schedule of operational loading of machines

For each job specified in the shift task, the worker receives either an order or a mock-up punched card (depending on the degree of mechanization of accounting work). Upon completion of the work and acceptance by the controller of the BCC, the worker's outfit is closed, and in the shift task the foreman makes a mark on the acceptance of the work.

There are various kinds of devices for the distribution of work. So, a distribution card file is used, in the cells of which working documentation is laid. By the location of the latter, one can judge the state of this work: whether it is assigned for execution, whether it is prepared for execution, or the worker has already received the task for its execution. Operational accounting of the implementation of the program by the main workshops in a single production is carried out according to the data on the implementation of the shift-daily task by each section. The objects of operational accounting are the development of workers, the movement of parts for operations, the receipt of workpieces, downtime of workers, marriage, the delivery of finished products. Accounting is based on primary documentation; production of workers - according to work orders, the movement of parts in production according to route maps, the receipt of blanks and the delivery of finished products - according to invoices, etc. Based on the data on the completion of shift-daily tasks and invoices for the delivered products, the foreman makes a mark in the schedule of the site about the progress implementation of the monthly program for each delivery item.

Single production is characterized by a large number of orders for the manufacture of various products in units and small, non-repetitive batches. At the same time, mechanical work predominates in some products, assembly work, etc. in others.

Therefore, operational planning should group the orders for launch in such a way as to ensure the best combination of production dates with a uniform load on the main shops.

In order to withstand such a condition at the enterprise, before concluding contracts with the customer, a preliminary calculation of the production cycle for manufacturing an order is made. Another distinctive feature of unit production planning is the inclusion in the order production cycle of all stages of pre-production and product manufacturing, i.e. development of design, technology, rationing of labor costs, design and manufacture of tooling, manufacture, testing and fine-tuning of products.

In unit production, operational management is carried out according to a custom system, in which the planned unit is an order for a product or an assembly connection.

The system is based on the development and observance of end-to-end cycle schedules technical training each order and production and its phased implementation, in conjunction with the cycle schedule for other orders.

Operational planning in unit production includes:

calculation of the production cycle for each order and calculation of the required number of jobs using the formula

, (9.1)

The complexity of this type of work on order;

- the actual fund of the operating time of the equipment.

On the basis of such calculations and taking into account the possible interoperational aging of parts, a volume-calendar schedule for order fulfillment is formed for each order (Fig. 9.2):

Rice. 9.2. Volumetric scheduling order fulfillment

The graph is built in the reverse order of the technological process. According to the schedule, the overall order production cycle is determined, which is compared with a given deadline.

Parts with a longer production cycle are put into production earlier than other parts in order to coordinate their uninterrupted flow to the assembly.

For mutual coordination in time and a more complete use of equipment and space for all orders, a consolidated volume-calendar schedule is compiled.

To avoid the overlap of work on the same equipment for several orders, it is necessary to adjust the deadlines for the work provided by the schedule for the implementation of individual orders. It is necessary to determine measures to eliminate bottlenecks and reload underloaded equipment.

The consolidated volume-calendar schedule is adjusted monthly, taking into account data on the implementation of the production program by the main workshops, the state of work in progress and the order for new tasks.

At the same time, the nomenclature and scope of work are being specified. Taking into account these features, the consolidated volume-calendar schedule of orders is finally specified and, on the basis of it, the PDO issues a monthly production program of work to each workshop in the form shown in Table 9.1.

Table 9.1

Monthly production program of the workshop

The PDB of the main workshop, having received a monthly production program from the PDO, distributes the work provided for in it among the production sites, makes volumetric calculations for the correct use of capacities and eliminates disproportions in the load of the equipment of the sites, and a schedule for the operational loading of machines is drawn up.

The basis of planned and distributive work for a shift is a shift-daily plan, in which the task is specified for each day and shift for each worker.

There are various kinds of devices for the distribution of work. This is how a distributive card is used, in the cells of which working documentation is laid. By the location of the latter, one can judge the state of this work: whether it is assigned for execution, whether it is prepared for execution, or whether the worker has already received the task for its execution. In addition, there is a control card with cells for the number of days per month.

Operational accounting of the implementation of the program by the main workshops in a unit production is carried out according to the replenishment of the shift-daily task by each section. The accounting objects are: the development of workers, the movement of parts for operations, the receipt of blanks, marriage, downtime, the delivery of finished products. Accounting is carried out on the basis of special primary documentation - according to orders, special route maps for the movement of products, according to invoices, etc.

In unit production, one product or a number of products of the original design is manufactured. Therefore, for each order, constituting one product or a small batch of products, technical documentation is developed, production is prepared, a production schedule is calculated, the cost is determined, production progress is monitored and recorded. Since individual parts and assembly units can be used in different orders, and some can be manufactured as original ones, the main task of operational scheduling under these conditions is the rational combination of fulfilling various orders within the time limits set for each of them. At the same time, uniform loading of all production sites and workplaces should be achieved.

OKP systems in unit production are least typed and focused on the methods of organization of production, labor and management that have developed at enterprises. Nevertheless, with all the variety of tools and methods used in operational scheduling, they must solve three important tasks:

Development of calendar and planning standards that regulate the progress of the order;

Planning of technical, organizational, economic and material preparation of production;

Application of serial methods of organization of production and operational scheduling in certain areas of production, specialized parts and assemblies.

Peculiarities intershop operational scheduling in unit production are as follows:

The annual output is distributed over periods within the year in accordance with the portfolio of orders, the order of receipt of orders and the conditions for loading production;

The lack of repeatability of orders does not allow the creation of reliable long-term scheduling standards.

Intrashop OKP is characterized by the fact that tasks for production sites and workplaces for each order are formed by sampling from the operational shop plan of the corresponding nomenclature, taking into account technological manufacturing routes. In addition, the tasks for the month regulate the timing of the production of leading and original parts and assemblies.

The terms of production of the rest of the nomenclature of the workshop are set in the order of the current distribution, depending on the workload of jobs.

Operational scheduling in unit production includes the following planned calculations (Fig. 3.6): calculation of the production cycle of order fulfillment and construction of a volume-calendar schedule for the fulfillment of individual orders and a summary for all orders; calculation of calendar deadlines for advances in the work of shops; calculation of loading of equipment and production areas in the planning period; daily account of the fulfillment of orders.

Figure 3.6 - Algorithm for operational scheduling of unit production

Payment production cycle for each order ) begins with the distribution of the complexity of the order by type of work and the calculation of the required number of jobs
(equipment):

where - the complexity of this type of work on order;

- the actual fund of the operating time of the equipment.

On the basis of such calculations and taking into account the possible interoperational aging of parts for each order, a volume-calendar chart order fulfillment.

The schedule is built in reverse order of the technological process, starting from the test or assembly shop. According to the schedule, the general cycle of manufacturing an order is determined, which is compared with a given period. For orders with a short production cycle (less than a month) and a small number of executing shops (one or two), a volume-calendar schedule is not drawn up.

Calculation of calendar lead times in the work of workshops is necessary for their coordinated uninterrupted operation and for all the parts included in this product to arrive for assembly by the specified date. Therefore, parts that have a longer production cycle are put into production earlier than other parts.

Consolidated volume-calendar chart the fulfillment of all orders is necessary for the mutual coordination of work on orders in time and for a more complete use of equipment and space. When constructing a consolidated volume-calendar schedule, it may happen that the deadlines for completing the same work on different orders on the same equipment coincide, and it turns out to be overloaded, or the deadlines for completing work on one order and starting work on another on the same equipment do not coincide, and this equipment is underloaded. In both cases, it is necessary to adjust the deadlines for the execution of work provided for by the schedules for the implementation of individual orders. At the same time, it is necessary to determine measures to eliminate bottlenecks and reload underloaded equipment. In order for the consolidated volume-calendar schedule to meet the above requirements, the PDO and PDB of the main workshops calculate the loading of equipment and the use of production areas, finding the best option for using the available capacities.

The consolidated volume-calendar schedule is adjusted monthly, taking into account data on the implementation of the monthly program by the main workshops, the state of work in progress on orders, and new orders accepted by the enterprise. At the same time, the nomenclature and scope of work for previously included orders are being specified. Taking into account these features, the consolidated volume-calendar schedule of orders is finally specified and, on the basis of it, the PDO issues to each workshop monthly production program works, which indicates the scope of work for each order and the timing of their implementation.

The monthly workshop program contains the following details:

Name and order code;

Name and code of the part (assembly unit);

The number of parts (assembly units) planned for release;

Launch-release dates;

The labor intensity of manufacturing a unit of production and the planned scope of work.

The workshop production program serves as the source document for compiling production site programs. To do this, the work envisaged by the program of the shop is distributed among the production sites, volumetric calculations are made for the correct use of capacities and the elimination of disproportions in the loading of the equipment of the sites. Sometimes, in addition to the monthly program, the PDB of the shop, before the start of the planning period, gives the foremen updated schedules for the distribution of work for shorter planning periods (decade, week). When determining the timing of the launch and execution of individual works, they are guided by the duration of cycles, current needs and the state of work in progress. The fulfillment of monthly tasks (schedules) must be fully provided with sets of working drawings and other technical documentation, materials, blanks, semi-finished products, parts, tools, production documentation, etc.

The basis of planning and distribution work for a shift is shift plan, in which tasks are specified for each day and shift for each worker. The reality of shift assignments must be ensured by advance and thorough operational preparation of production. Shift tasks include only such work for which technological documentation, tooling, materials and workpieces have been prepared.

Operational accounting of the implementation of the program by the main workshops in a unit production is carried out according to the data on the implementation of the shift-daily task by each section. The objects of operational accounting are the development of workers, the movement of parts for operations, the receipt of workpieces, downtime of workers, marriage, the delivery of finished products. Accounting is carried out on the basis of primary documentation processed on a computer using machine-readable documents.

Single production is characterized by the manufacture of various products in single or small batches. The repeatability of the release of products in a single production is either absent or irregular and does not affect the essential features of the production process.

The main task of operational scheduling under these conditions is to ensure the timely fulfillment of various orders in accordance with production programs with uniform loading of all production links and the shortest production cycles for order fulfillment.

A characteristic feature of operational scheduling is the close connection between the scheduling calculations of production and the planning of the technical preparation for the fulfillment of each order. In unit production, increase specific gravity unified and standard components of manufactured products. This allows you to apply group technologies, specialized areas and multi-subject production lines for the processing of standardized parts and assemblies, to plan their production in batches to the warehouse.

Order Fulfillment Process consists of the following stages: placing an order, preparing an order fulfillment, order fulfillment. Let's consider each of these stages separately.

Checkout- it is necessary to use enlarged standards determined by experimental-statistical methods. The sequence of placing an order in machine-building production is shown in Figure 16., The main elements of which are the portfolio of orders, a request sheet (a document in which all wishes, requirements, calculations of performers are entered in the sequence indicated in the diagram), an order card, an agreement (contract) for execution order. Each executor sends the request sheet to the order bureau and the next executor in the cycle. The following abbreviations are used: OGK - department of the chief designer, OGT - department of the chief technologist, OMTO - department of logistics, PO - production department, PEO - planning and economic department.

Figure 16. Sequence of placing an order in machine-building production

Order fulfillment preparation.

Scheduled calculations in unit production include:

1. calculation of the duration of the production cycle for the manufacture of products (fulfillment of orders) and the construction of cycle schedules for individual orders;

2. determination of calendar advances in the work of shops;

3. compilation of a consolidated calendar schedule for the fulfillment of orders accepted for production, and the subsequent clarification of calendar advances in the work of shops;

4. verification calculations of the loading of production areas and equipment (volume-calendar calculations and adjustment of the summary schedule in order to equalize the load for individual planning periods.

Payment duration of the production cycle order fulfillment is the main calendar and planning calculation in unit production. This duration is determined by the formula:

Tc \u003d n? (tc / csq) + m (tmp / sq) + tc

TC - the duration of the production cycle;

n is the number of parts in the batch;

m is the number of operations of the technological process;

tk is the total time limit for the operation;

c is the number of workplaces occupied in parallel by the operation;

s is the number of work shifts per day;

q is the duration of the work shift;

tmp - interoperative time;

tc - duration of natural processes;

The assembly of products can be sequential, that is, after the assembly of one product, the assembly of another begins, and parallel, when all the products of the series are assembled at the same time. When assembled in series total build time is determined by the formula

Tpsb \u003d nc Tsb

nс - number of products in a series

Tsb - the duration of the production cycle of assembling one product

With parallel assembly, the total assembly period coincides with the duration of the production cycle for assembling one product.

For each order, the labor intensity of the operation by type of work is summed up in order to determine the load for each type of equipment and workers. The form of the cyclogram for the manufacture of products is shown in Fig. 17.

Figure 17. Cyclograms of manufacturing products

Procurement, preparatory operations

Interproduction breaks

Technological processing

Final operations (assembly, packaging, etc.)

Order fulfillment is carried out sequentially according to operational scheduling.

Operational scheduling in a single and small serial production consists in drawing up monthly operational programs for workshops, accounting for their implementation and intra-shop operational and scheduling, compiling shift-daily tasks for sites and workplaces, and recording them. Planning and accounting units are:

· in assembly shops there are products, or assembly units of the corresponding name;

· in processing and procurement workshops - orders in general, assembly kits and route assembly kits.

In accordance with this, in single-piece and small-scale production, it is advisable to use a complete assembly system of operational production planning, in which the lead in production for all parts of a given assembly unit is taken equal to the largest lead in the release of one of the parts processed in this workshop of this assembly unit. In the manufacture of labor-intensive parts that pass through several shops, work in progress increases, to reduce it, the parts of one assembly unit are divided into sets with the same technological routes for their processing in subsequent shops (Fig. 18, 19)

Figure 18 Technological routes for processing parts of an assembly unit by workshop.

Figure 19 Sets of parts of an assembly unit with the same technological routes.

An operational plan for three months is issued to workshops either at the beginning of each month or at the beginning of a quarter. At the end of the first month of the quarter, adjustments are made to the remaining two months and the plan for the first month of the next quarter is added to them, taking into account advances. The timing of the release of parts included in the assembly kit is determined by subtracting the advance release established for this assembly kit from the release date of the finished assembly units.

The terms for the release of products are set in aggregate by decades or weeks based on sales. For clarity, the loading of equipment on orders is represented graphically (Fig. 20)

In the event that the percentage of readiness at the beginning of the month actually turns out to be less than planned, the shop in the current month will have to perform a larger amount of work for this planning and accounting unit than provided for in the program so that the percentage of readiness at the end of the month is not lower than the established . The form of the monthly operational program is shown in Fig. 21. It is more expedient to draw up the procedure for compiling monthly operational tasks for sections in a detailed section (Fig. 22). The release date of the part of the corresponding name is determined by subtracting the duration of the production cycle of assembling the assembly unit and processing the part after this section from the release date of the assembly unit set in the monthly program for the shop.

For subject areas specialized in assembly units, monthly operational tasks are made up of a sample of the number of assembly units and the timing of their release from the monthly program for the workshop.

For areas where a small number of labor-intensive parts are processed, the monthly task can be drawn up in the form of a schedule for loading workplace equipment.

For assembly sites, it is advisable to draw up schedules for the assembly of products in the operational section

Production program for the machine shop for March 2006

Figure 21 Production program for the machine shop.

Assignment to the site for March 200--g.

Figure 22 Site assignment.

Equipment loading schedule plan (in the numerator is the part number in the denominator is the number of the operation)

Figure 23 Equipment loading plan

Decade tasks are for sections and parts with a long production cycle. These tasks are either in the form of a schedule for loading equipment, or in the form of a task for a decade in the operational section for each part or assembly unit.

Shift-daily planning and accounting for monthly and intra-month tasks is carried out as follows: when processing labor-intensive parts, the shift task indicates the percentage of readiness of the part if its processing cannot be completed during this shift. If there is a norm of time for transitions in a shift task, transitions can be indicated, according to which the part must be processed during the shift.

Figure 24 product assembly schedule plan

Accounting for the implementation of monthly tasks and programs for workshops is carried out in the same forms in which they are compiled.

Based on the schedule for the passage of the PDO order, updated quarterly and monthly calendar schedules for the preparation of production, manufacture and testing of this product (order) are developed.

Since the order for the development and manufacture of a product includes technical preparation for production, which requires a significant period of time (sometimes more than one year), operational scheduling becomes prospective and it becomes necessary to break down the volume of its work not only by quarters and months, but also by years and determine the duration of the production cycle and advance launch and release by stages and stages of technical preparation, production of components and parts, as well as the overall assembly of the product. To solve these issues, it is necessary to build a cycle schedule for assembling and testing the product for this order, taking into account the duration of the cycles for manufacturing parts of each assembly unit included in the product.

The duration of the cycles of manufacturing parts and the duration of the cycle of assembly units can be determined by the formulas. However, before proceeding with the calculation of the duration of the production cycle for the manufacture of parts and assembly units, it is necessary to determine the sizes of batches of parts and products to order, arising from the annual (quarterly) production plan. The sizes of batches of parts can be determined by formulas, and the number of products from a consolidated order.

On the basis of the cycle schedule, the timing of the launch and release of parts and assembly units, the normative advances in launch-release and the duration of the product production cycle are set.

According to the revised cycle schedule, it is possible to establish the sequence and timing of the supply of parts, assemblies, subassemblies and small assembly units for the assembly of the product and thereby determine the timing of their release. The launch dates are calculated based on the established release dates and the amount of lead determined by the cycle schedule. With such planning, the minimum periods of soaking of parts before assembly are achieved.

The timing of launching blanks into production is set according to the timing of their release, which, in turn, is determined by the timing of launching at the processing stage and the duration of the cycles of procurement processes.

After determining the duration of the cycles of individual stages of production (procurement, processing and assembly), the total duration of the product manufacturing cycle is established according to the cycle schedule.

Calendar cycle schedules are developed first for each individual order, and then on their basis a consolidated volume-calendar schedule is compiled for the entire portfolio of orders for a given planning period and for each workshop. At the same time, it is necessary to ensure such loading of all production links so that it corresponds to their requirements. bandwidth and was uniform throughout the planning period. To solve this problem, calendar-volume calculations are carried out and corresponding graphs are built, in which they show the mutual linkage of the calendar deadlines for the implementation of individual orders and the loading of production equipment and areas.

An example of a volume-calendar schedule for the execution of one order is shown in Figure 5.2. When constructing such a graph, the scheme is sequentially applied to the load value by order executors in the form of rectangles, each of which indicates: vertically - the number of jobs occupied by the execution of the order, and horizontally - the calendar period of the work. Then the schedules of all orders are linked in a consolidated volume-calendar schedule (Fig. 5.3). The latter contains the scope of work and deadlines for all orders included in the program.

In the consolidated volume-calendar schedule, the deadlines for performing the same work on different orders on the same equipment may coincide, and then it will be overloaded, or the deadlines for completing work on one order and starting work on another on the same equipment will not coincide, and this equipment will be underloaded. In both cases, it is necessary to adjust the deadlines for the execution of work, provided for by the cycle schedules of individual orders. At the same time, it is necessary to determine the measure to eliminate bottlenecks and reload idle equipment.

The corrected summary volume-calendar schedule of order fulfillment is the starting point for compiling the production program for the operational task of each workshop of the enterprise for the planning and accounting period (month, decade or week). This task should follow from the plan for a longer period.

Rice. 5.2.

Rice. 5.3.

The task for individual workshops should be drawn up by the chain method - in the reverse order of the technological process, i.e. from assembly work to procurement operations. The first task is drawn up for the producing workshop, for example, for assembly and finishing, the basis for it is the factory program for the production of finished products. Next, a launch task is compiled for the same workshop. Based on the task for launching the assembly shop, the task is determined for the production of a mechanical shop that feeds the final shop with its products, and then the task for launching the same processing shop. On the basis of the task for launching the processing shop, a task is developed for the release of the procurement shop, and finally, on the basis of the latter, the task for launching this shop is developed.