Features of operational scheduling of a single type of production. Operational scheduling of unit production

The functions, tasks and presentation of production planning data largely depend on the type of production. For single and small batch production tasks scheduling can be presented in the form of two interconnected blocks: volume-calendar planning and operational-calendar planning.

The tasks of volume-scheduling can be defined as follows:

• assessment of the feasibility of production plans;
• formation of preliminary plans for the course of the production process;
• formation of planning documents based on the solution of these tasks.

The tasks of operational calendar planning include the formation of production schedules and the formation of planning documents in accordance with the operational plan.

The volume and composition of information used for volumetric and operational planning differ significantly.

In this article, we will restrict ourselves to the consideration of volume-scheduling for single and small-scale production.

Formation and maintenance of basic information for space-scheduling tasks

Formation and maintenance in the system of a database on the products of the enterprise, their structure and composition

The processes of generating and maintaining data on the structure and composition of products for the planning system must meet two basic requirements:

• information must be up-to-date at any given time;
• the processes of maintaining and keeping up-to-date product data should be natural business processes of the enterprise and performed in the departments responsible for this data.

To the greatest extent, these requirements are met by maintaining data as part of an engineering data management system (PDM), adapted to current standards and including change management modules, and for enterprises that produce products with a large number of configuration options, configuration management modules.

The domestic automated production control system Omega Production meets these conditions. The engineering data management subsystem provides basic information to the planning subsystem, subsystems inventory management, quality, etc. There is also the possibility of importing data on the structure, composition and changes from the design archive system Search NPP "Intermeh".

The engineering data management subsystem in Omega Production also provides the ability to maintain information about workpieces (forgings, castings), their changes and links to parts. This allows you to include in the scope of planning and metallurgical production of the enterprise.

Management of engineering data and their changes is based on a universal built-in technical document management system.

Determination and maintenance of the considered nomenclature of elements in the composition of products

The results of volume-calendar planning are traditionally drawn up in the form of various schedules that limit the number of elements presented. Because of this, and also in connection with the preliminary, evaluative nature of space-scheduling, for calculation and presentation, usually not the entire composition of the product is taken, but only its most labor-intensive and critical components - the so-called considered nomenclature. This limitation is not “machine” (that is, the solution and presentation algorithms do not depend on the number of components), but rather “human”, determined by the user's ability to perceive and analyze data.

The products of the considered nomenclature are associated with data on the technological cycle of manufacture, the development cycle, the pre-production cycle, and in addition, the number of products required for design and technological tests (which is typical for pilot and single production), and the yield factor of good products are indicated.

Maintenance of data on the types of work by the shops of the enterprise and the throughput of the shops by types of work

In volume-scheduling, calculations of loading and throughput of workshops are usually performed at the level of types of work. Therefore, the system has a directory of types of work for the tasks of space-scheduling, on the basis of which data on the types of work for the shops of the enterprise is entered. Types of work in the workshops of the enterprise are the basic elements for the tasks of technological routing of products and receipt of cover sheets. For the types of work in the workshops, a certain typification is used, which makes it possible to formalize the control of technological routes and automatically determine the production signs of manufacturing products.

Data on the types of work by workshops can also be obtained by importing from the TechCard technological process design system of NPP Intermekh.

By type of work in the workshops, information is kept on annual and monthly funds of time for two- and three-shift operation.

Maintenance of data and expert assessments of labor intensity by type of work for products and blanks

The sequence of work on a product/workpiece determines its technological route at the level of types of work. The system has advanced functionality for creating and maintaining data on technological routes, managing their changes and receiving different kind reports. This functionality is applicable for serial production as well as for small-scale and one-off production.

Expert estimates are the most aggregated data on labor intensity and are used to solve the problems of space-scheduling. Therefore, expert assessments of labor intensity by types of work can only be specified for products of a selected nomenclature that are taken into account in tasks of space-scheduling.

According to the type of work, the complexity or duration of the cycle can be set (Fig. 1). Recalculations of labor intensity into the duration of the technological cycle and vice versa are performed using information on the number of workers according to this species work, shift duration and taking into account the shift coefficient, the coefficient of overfulfillment of the norms for the workshop, the coefficient of interoperational sojourn. Information about the duration of the shift, as well as the values ​​of the shift ratio and the coefficient of overfulfillment of the norms for the workshop are taken for calculations from the parameters of the workshop.

Maintaining business order book data

Order to production is important production document, which goes through the approval and approval procedures. Therefore, order management for production is implemented in Omega Production within the framework of the general scheme of technical document flow. For an order, the system administrator at the enterprise can create an adequate life cycle with the corresponding schemes and coordination functions for promotion operations. A standard revision mechanism is used to keep changes on orders in production.

Orders are generated and maintained for both final products and components. At the same time, for final products, both standard specifications for versions and specifications for custom-made configurations obtained using the mechanism for configuring products for a functional specification of an order can be used.

Solving problems of space-scheduling

Maintain Plan Data for Order-Based Production

Plans in the system are objects of technical document flow, therefore they have all the properties typical for such objects: an assignable life cycle with different user rights by status and ownership rights, assignable validation rules, assignable approval/approval schemes, the ability to distribute via built-in e-mail, change management using the revision mechanism, etc.

The plan may consist of, for example, sections such as main products, spare parts, related products, etc. Each section of the plan can have its own data source for plan elements, which allows more reliable control over the correctness of the specifications included in the product plan.

For each of the elements of the plan, a planning attribute and a start time or release time can be specified. The following planning-to-order characteristics are currently supported for elements: design and build-to-order, build-to-order, build-to-order, repetitive production. In the first case, it is assumed that, at least for some of the products and their elements, the order documentation has not yet been brought to the production level, and planning should include information on the cycle of development and pre-production of the product. In the second case, only the product manufacturing cycle is taken into account in the calculation of the plan. In the case of assembly to order, it is considered that the elements for assembly are already available in the required quantity or there are backlogs for them sufficient to carry out the assembly in parallel with the manufacture of the missing elements. In the case of mass production, the production cycle of the product is determined by the rhythm of the conveyor.

According to the plan element, the current state of its production at the beginning of the planning period or at the date of launch into production can be set, which includes not only the number of products in this state, but also the labor intensity performed for the current type of work (Fig. 2).

Features of the plan calculations

The options for making calculations are:

• accounting in products-products of products of return cooperation;
• calculation of the number of blanks (if the part route does not take into account the part that belongs to the blank);
• the ability for each of the products to set their own color scheme and execution.

For products of the considered nomenclature, the following options can be set: accounting for blank cycles, accounting for the need for products for design tests, accounting for the need for products for technological tests, accounting for the yield factor of good products.

When calculating the plan, it is mandatory to calculate the composition for the elements of the plan. The composition of the product in the plan depends on the initial state of the element of the plan.

If the initial state is not specified, then the entire composition is taken for the plan, including the product itself. If it is not necessary to take into account products of return cooperation as part of products-products, then purchased products are not disclosed. If it is necessary to take into account products of return cooperation in products, the composition of purchased products is disclosed. From the composition of purchased products, products of return cooperation are included in the composition of the product-product. The assignment of the product in the composition of the purchased item to the products of return cooperation is based on the analysis of its routes. If you need to calculate the number of workpieces, then for the part, the presence of the workpiece and the number of parts obtained from the workpiece are analyzed. If there is a blank, it is also included in the composition of the product.

When specifying data on the state of product-products at the beginning of the planning period, in the absence of data on assembly maps, the composition can only be calculated with an accuracy of a route point (type of work). The product-product is divided into groups that differ in the initial state. For each of the groups, the composition is calculated only for the remaining types of work.

The number of records for one composition item, one occurrence, one applicability, one order, and one section of the plan depends on the type of route for the item. There is a set of rules for choosing a route for a plan product in the presence of alternatives. If the product has parallel routes, then all of them are taken into account in the plan.

Calculation and presentation of summary schedules for the manufacture of products-products and schedules for the manufacture of products of the considered nomenclature

Schedules for the manufacture of products of products and products of the considered nomenclature can be obtained on the basis of the following data: on the technological cycles of manufacturing products without taking into account the types of work, on the labor intensity (technological cycles) of manufacturing products by type of work. In the first case, much less initial data is required, which is important for estimated planning. But at the same time, only the total duration of each cycle and the launch-release time of products are determined. In the second case, the complexity of maintaining the initial data is higher, and not only the duration of each cycle is determined, but it is also possible to assess the feasibility of the production program by workshops and types of work based on the calculation of the equipment load.

The central link for the calculation of schedules is the determination of the general cycles of manufacturing products. Algorithms for determining general cycles depend mainly on the characteristics of order-based planning and the initial state of plan elements. For example, for development and customization, the calculation algorithm is performed under the following assumptions:

• the batch size for each of the products of the considered nomenclature of the composition is taken equal to the requirement, taking into account (if the corresponding option is set) the number of products for design tests, technological tests and the yield factor of good products;
• the first product-product is created sequentially, that is, at first the components are created taking into account the hierarchy of entry, and when they are ready, the product itself;
• for subsequent products in the batch, assembly is performed in parallel with the manufacture of components;
• the general cycle takes into account the time for the development and technological preparation of production for the product.

The definition of general cycles and the presentation of schedules (Fig. 3) in calendar time depends on the assignment of the release date or launch date for the element of the plan. If the release date is set as a calendar date, the total cycle is subtracted from it and the launch date is determined. If the launch date is set as a calendar date, the general cycle is added to it and the release date is determined. In this case, the specified option for accounting for weekends and holidays is taken into account.

Calculation and presentation of schedules and workloads by workshops and types of work

The use in calculations of data on labor intensity by type of work in workshops in accordance with the technological routes of products makes it easy to attach general schedules for products of the considered nomenclature into schedules for the launch and release of products for given workshops, by workshops and types of work or by types of work in the whole enterprise. The presentation of schedules for workshops and types of work is similar to how it is done for general cycles.

The availability of information on the available funds of time by type of work in the shops allows you to calculate the load by type of work in the shops and by shops as a whole. The definition and presentation of load is carried out in two ways: as an average load for the planned period, which is calculated in the form of load factors, which are the ratio of the amount of labor intensity in a given period to the available time fund for a given period; in the form of load diagrams for the planned period, allowing to present the change in load over time in accordance with the schedules for the launch and release of products. The second way of presenting the load is much more visual and allows you to interactively redistribute the labor intensity by type of work (Fig. 4), taking into account their connectedness, in order to avoid peak loads and increase the uniformity of equipment load by type of work.

The formats of the submitted output documents for space-scheduling are usually specific to each of the enterprises. The system has a form generator that allows you to properly generate the format of output documents, including built-in graphic diagrams.

"CAD and graphics" 6 "2001

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.

Based on 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 of order fulfillment

The graph is built in reverse order 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 a special primary documentation- according to orders, special route maps for the movement of products, according to invoices, etc.

Operational scheduling in mass production

Significant number engineering enterprises have serial production. Serial plots, as a rule, are at enterprises of all types of production.

The objects of planning in mass production are a series and a batch of products. Under series is understood as the number of identical in design and technical specification products. Serial production is characterized by the processing of parts and assembly units parties. Under party refers to the planned and accounted number of identical parts or assembly units that are simultaneously put into production and processed with a single cost of preparatory and final time.

Intershop OKP in serial production is characterized by the following features:

The movement of production in time is determined by calendar and planning standards, on the basis of which operational plans are developed;

Fixing the nomenclature of parts and assemblies for workshops and workplaces becomes permanent in accordance with their specialization;

The nomenclature of workshop programs is built in a complete set (for a product, unit, group);

Quantitative tasks are determined by picking numbers;

The calendar distribution of tasks is carried out in the form of setting the dates for the launch and release of batches of parts.

Intrashop The OKP of serial production is characterized by the fact that with a complete system, quantitative tasks for sections are determined in itemized nomenclature-quantitative positions established by the division of sets provided for by the workshop plan, and the program sets the launch and release dates for the corresponding batches of parts for a month.

Serial production planning is based on scheduling standards, including: batch size of the product; the frequency of launching batches; production cycle; advancing the launch-release of batches of parts, assemblies and products; the level of backlogs and total work in progress. Using these standards, they build calendar schedules for the work of production teams and sites.

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, a technical documentation, preparation of production is carried out, the production schedule is calculated, the cost price is determined, control and accounting of the production progress is carried out.

OKP systems in unit production are focused on the methods of organization of production, labor and management that have developed at enterprises and are the least typed.

Peculiarities intershop OKP in a single production are reduced to the following:

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. Only cyclic graphs and calculations can have a normative character
for similar orders;

The assignment of the nomenclature to workplaces, workshops and sections may vary from one order to another;

The nomenclature of workshop programs is built within the framework of an order-by-order and, less often, a complete-assembly planning system;

Calendar tasks for the fulfillment of orders are distributed on the basis of the established deadlines for the delivery (picking) of orders, taking into account calendar advances in the work of sections and shops.

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.

OKP in a single production includes the following planned calculations: 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.

In a single type of organization of production, three systems of operational production planning are used: order-by-order, complete-node and item-warehouse.

At order system the planning and accounting unit of the production program is order or set of parts to order. This system covers all manufacturing process order fulfillment, including the stage of technical preparation of production, which takes a significant specific gravity(especially in mechanical engineering) in the overall production cycle. Thus, in the machine tool industry, the technical preparation of production is 50–55% of the total order manufacturing cycle.

Calendar-scheduling calculations of the production program are carried out in the reverse order of the technological process from the producing shops to the procurement ones. For each workshop, they plan the timing of the order, as well as the timing of launching the order into the production process.

The most important calculations according to the calendar and planning standards of the order system are:

• - calculation of the duration of the production cycle for the manufacture of products (fulfillment of orders) and the construction of cycle schedules for individual products (orders);
• - determination of calendar advances in the work of shops;
• - drawing up a consolidated calendar schedule for fulfilling orders and clarifying calendar advances in the work of shops;
• - verification calculations of the load of equipment (production areas) and adjustment of the summary schedule in order to equalize the load for individual calendar periods.

Production cycle(the most important standard for the organization of production) - a calendar period of time from the moment raw materials and materials are put into production until the moment the finished product is released.

Cycle duration (tc) includes the time of productive work and the time of breaks (intra-shift, inter-shift). For a product, ts is determined by the labor intensity of the leading node (part, type of work) and is measured in calendar days.

The calculation of the duration of the production cycle is carried out in the reverse order of the technological process: from the producing shops to the procurement ones and is calculated by the formula

where P - the number of parts in the batch; t – number of operations in the process; t k - the norm of time for the operation; with – the number of jobs parallel occupied by the operation; s is the number of work shifts per day; q - the duration of the work shift; t mn – interoperative time; te is the duration of natural processes.

The calculation of tc by the enlarged method is carried out according to the formula

where th is the labor intensity of the leading node (part) or work; k - coefficient of compliance with the norms; g - composition of the brigade; s - the number of working shifts per day; q - the duration of the work shift.

In calendar days

where k k.d – coefficient of calendar work, equal to the ratio of the number of calendar days in a year to the number of working days in a year.

Based on the calculations of the duration of the assembly cycle of the product, the duration of the cycle of processing parts and the manufacture of blanks, the duration of the cycle of manufacturing the order as a whole is determined and developed cycle schedule for order fulfillment, which is the most important document of interdepartmental operational planning in the order system.

Cycle schedules for individual orders and the timing of delivery of orders to the consumer serve as the basis for the development of a consolidated schedule for the launch-release of order fulfillment for the planning period. This schedule links the work of all departments to fulfill orders.

The development of a summary schedule is accompanied by verification volume-calendar load calculations equipment (production areas) to fulfill orders. These calculations should clarify how throughput equipment of workshops ensures the possibility of manufacturing an order within the planned time frame.

Volumetric-calendar calculations of equipment loading are carried out in the reverse order of the technological process, i.e. from assembly shops to blank production.

An important standard of the order-by-order system is the lead time (O) both for private production processes and for all workshops of the enterprise.

Advance- the period of time (in days) by which the previous private production process must be ahead of the subsequent process in order to complete it on schedule.

The calculation of advances is based on the duration of the production cycle of manufacturing the product. The advance value is equal to the total duration of production cycles from the date of completion of the manufacture of the product to the technological stage by which the advance is determined. Wherein t calculated in the direction opposite to the course of the production process, with the addition of the reserve time between stages (tres).

Example. The part is processed at three stages of the production process: procurement, mechanical and assembly duration, respectively, 7, 11 and 10 days. Reserve time - 2 days. It is necessary to calculate the amount of advance.

Let's determine the total £c of the product: t c.sb + t cut + t fur + t cut + t c.zag \u003d 10 + 2 + 11 + 2 + 7 \u003d 32 days. This means that the advance in launching the product into the production process relative to its delivery to the finished product warehouse is 32 days. Then the standard for advancing the launch of the product to the assembly shop Oz.sb is 10 days.

The output lead norm for the machine shop is equal to: Op.m = £c,b + Ov.m = t c.sb + t res = 10 + 2 = 12 days.

The norm for advancing the launch of the product into the machine shop is equal to: Oz.m = t c.sb + t cut + t c.fur \u003d 10 + 2 + 11 \u003d 23 days.

The standard for advancing the release of the product in the procurement shop is equal to: Oz.m = t c.sb + t cut + t fur + t res = 10 + 2 + 11 + 2 - 25 days.

The standard for advancing the launch of the product in the procurement shop is equal to: Oz.z \u003d t c.zag \u003d 25 + 7 \u003d 32 days, i.e. the total duration of the production cycle (Fig. 5.2)

The objects of operational accounting and control in the system shown are the deadlines for the fulfillment of orders by workshops, as well as their cycle schedules.

Rice. 5.2.

Complete-nodal system identical in content to the ordering system. Choice in this case one of the two systems is determined by t c.

If a t less than 1 month, then the order-by-order system is used, in which all components and parts necessary for the assembly of the product are completed before the start of assembly work. If a t more than 1 month, then a complete-assembly system is used, in which the assembly is completed as components and parts are manufactured.

The planning and accounting unit for the enterprise in this option is the technological unit, and for the workshops - a set of parts for it.

Part-warehouse system (maximum-minimum system) is used both in single and serial types of production organization. Operational planning for this system concerns the production of unified and standardized parts for general use.

With this system, a batch of manufactured parts is delivered to the workshop warehouse. Three types of stocks of parts (reserves) are calculated: maximum, minimum, and stock of a reorder point. The stock flow diagram (Z) is shown in fig. 5.3.

The functioning of this planning system is carried out by constantly restoring stocks to the initial level.

Minimum stock Z min – it is a reserve, the use of which is necessary in extreme cases.

Rice. 5.3.

where AT s.d - average daily output of parts; t op - the time of manufacturing the part.

The maximum stock of parts is equal to:

where - the size of the batch of parts received from the workshop to the warehouse; t - the time between two successive deliveries to the warehouse of a batch of parts.

The reorder point stock is equal to the volume of parts in the warehouse at which the warehouse issues an order to the workshop for the manufacture of the next batch of parts:

The warehouse should systematically monitor the state of stocks of parts using a special itemized card file: a card is entered for each item, which contains the part number and its name, the manufacturing workshop, and the size of the insurance reserve. The cards mark the movement of each part in the warehouse. With their help, the actual state of the backlog and the timeliness of the launch of parts into production are controlled.

Intra-shop operational and production planning performs the following functions in a single production:

• – bringing the monthly production workshop program to each site and workplace in the form of a set of parts to order or a unit;
• – clarification of the workshop calendar plan work on the implementation of individual orders;
• - organization of the development of shift-daily tasks for workplaces, i.e. determination of the time of launching parts into production;
• - ensuring operational preparation for the implementation of shift-daily plans at the workplace, i.e. checking the availability of the workshop and each workplace with blanks and semi-finished products in accordance with the allocated limits for material resources and technological equipment;
• - control of the implementation of the workshop production program by sections and teams.

All these functions of the intrashop OKP are performed by employees of the shop production and dispatching bureaus.

It should be noted that the reserves for increasing the efficiency of a single type of organization of production is an increase in the proportion of unified and standardized parts and assemblies. Thus, in mechanical engineering, the share of unified parts and assemblies averages 40–70%, which makes it possible to create specialized sections and multi-subject production lines for the processing of these parts, i.e. to introduce elements of a large-scale type of organization into a single production. Significantly increases technical level unit production and improve its economic performance by introducing a mass production system, in particular complete group system OKP. Its essence lies in the fact that a group launch into production of parts of different names and sizes, but with structural and technological similarities, is organized.

Such a launch should be preceded by a major preparatory work according to the classification of parts, technological processes and technological equipment into groups on the basis of constructive and technological similarity.

The production program of the workshop is planned in sets of parts belonging to a particular group.

Single production characterized by irregular repeatability or non-repeatability production work when products are made special purpose in small quantities(for example, the manufacture of individual copies of non-standard equipment, large machine tools, dies, rolling mills, powerful turbines, etc.). This production is divided into a single one-time, repeatable and experimental.

Pilot production means production of samples, batches or gray products for carrying out research work or for the development of design and technological documentation for the established production.

Unit production enterprises produce a large range of products, as a rule, not repeated during the planning period. Production is carried out mainly on universal equipment located in the workshop on a group basis. In the assembly shops, small-scale unit and object assembly is carried out. In accordance with the nature of the universal equipment, the jobs of a unit production are loaded with various works according to the approved plan. Single production is characterized by the manufacture of various products in single or small batches, the implementation single orders in various industries and fields of activity.

The most complex industry is mechanical engineering. Having studied the approaches and methods on the example of a complex industry, it will not be difficult to apply the knowledge gained in a simple industry structure, for example, in the consumer services industry. At the same time, it should be remembered: the simpler the sectoral structure, the less calendar and planning calculations should be. 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 accounting and planning unit in unit production is the order. So the main task operational scheduling (OCP) in these conditions is to ensure the timely execution 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 the OKP in the conditions of a single production is the close connection between calendar and planning calculations with the planning of the technical preparation for the execution of each order.

In unit production, the proportion of unified and standard components of the output should be increased. This makes it possible to apply group technologies, specialized sections and multi-subject production lines for the processing of unified parts and assemblies, to plan their production in batches to the warehouse.

Recall that the order fulfillment process is divided into three stages. Let's consider the features of the OKP on them. At the stage of placing an order, it is necessary to use enlarged standards determined by experimental and statistical methods. Each executor sends the request sheet to the order bureau or to UMIS and the next (in the cycle) executor. A feature of operational production planning in unit production is underdeveloped compared to mass and serial production normative base.

The main calendar and planning standards are:

• the duration of the production cycle for the manufacture of products (fulfillment of orders);
• order fulfillment schedules,
• cycle schedules of production (for individual orders and a consolidated calendar schedule for the fulfillment of orders accepted for production, and subsequent clarification of calendar advances in the work of shops),
• volumetric calculations of equipment load (i.e. verification calculations of the load of production areas and equipment (volume-calendar calculations) and adjustment of the summary schedule in order to equalize the load for individual planning periods),
• determination of the magnitude of calendar advances.

The calculation of the duration of the production cycle for manufacturing a product (order) can be performed using the formula

TC \u003d uP * k / s ^ x?) + wx? mp /.vx d+ *e, (5.2)

where TC is the duration of the production cycle for manufacturing a product or fulfilling an order, slave. days; P- the number of parts in the party; t- number of technological process operations;

Total time for the operation, h; with- the number of jobs, parallel occupied by the operation;

^ - number of work shifts per day; q- duration of the work shift, h;

Interoperative time, h;

and- the duration of natural processes (drying, surface alloying, cooling after heat treatment, etc.).

On the basis of such calculations and taking into account the possible laying of parts, a volume-calendar schedule for the execution of the order is formed for each order (Fig. 5.1).

The schedule is built in the 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), the volume-calendar schedule is not drawn up. The calculation of calendar lead times in the work of workshops is necessary to coordinate their uninterrupted operation and to ensure that all parts included in this product arrive at the 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. Such a schedule is adjusted monthly, taking into account data on the implementation of the monthly program by the main workshops, on the state of work in progress on orders, on new tasks 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.

Rice. 5.1. An example of a volume-calendar (cycle) order production schedule

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.

In a single production, volumetric calculations are related to the CPD. This is because the resources production capacity over a certain period of time are constant, while the required power for different groups equipment changes significantly over time. This circumstance makes it necessary in each planning period to determine the required number of machine hours for the leading equipment groups of all orders to be manufactured in this period, and compare them with those available. This allows you to take timely measures to eliminate both overload and underload of individual groups of equipment, changing the timing of work on some orders and adjusting the estimated start-up time, thereby specifying the size of the lead compared to the calculated one. On the basis of such an adjustment, the final binding of the deadlines for fulfilling orders to the calendar time of a certain planning period is carried out.

The basis of planning and administrative 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.

The worker receives an order or a mock-up punch card (depending on the degree of mechanization of accounting work) for each job in a shift task. After the work is completed and accepted by the controller, the work order is closed, and in the shift task the foreman makes a mark on the acceptance of the work.

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: the output of workers is determined by work orders, the movement of parts in production - by route maps, the receipt of blanks and the delivery of finished products - by waybills, material consumption - by bill of materials and orders, etc. Based on the data received, the foreman makes a mark in the site schedule about the implementation of the monthly program for each worked position.