CAD/CAM/CAE Observer #8 (108) / 2016
The modern development of the economy is determined by increased competition in the market, new technologies in the production of goods. The most important factor in the efficiency of enterprises becomes the ability to create and organize the production of a wide range of products and their modifications in the shortest time in accordance with the needs of the market, in the conditions of the maximum possible optimization of the costs on material and labour resources required for the production process. The role of such factors as speed of managerial decision making, optimization planning taking into account resource limitations, and dispatching of production increases.
If we talk about information systems, the basic general mechanical engineering systems of technological preparation of production (TPP) assume the availability of the elaborated and approved electronic design composition of the product to be launched into production. Production planning systems are built on the assumption that before the start of production, the technological descriptions of processes (route manufacturing process) with the calculation of precise data – on the order of operations, material and labour regulations – are already known or will be worked out in detail. This approach leads to delays in the organization of production.
The existing variant of launching design documentation into production on the basis of tentative data for new parts and assembly units (PAU) or data on previously produced analogues – that is, without registration of detailed TP and calculations of material and labour resources – leads to the fact that planning is based on “rough” information that does not correspond to the real situation.
List of launch documents
Elaboration of the design and technological specifications
Materials and samples rating
The solution to reduce the time to “bring” products to market and improve the quality of production planning and the formation of up-to-date information on manufactured products can be as follows: implementation of a step-by-step (batch) model of launching the design documentation (DD) into production with the parallel enlarged technological preparation. This model of product preparation and launching into production implies that production processes for product components start before the entire set of design and manufacturing documentation (MD) for the product is completed.
Production Plan Management
Management of material needs
This methodology is widely used in prototype aircraft engineering, shipbuilding, and single-piece mechanical engineering, where the product design and manufacturing cycle is more than two to three months.
With this production model, those parts of the products, for which there is a DD, are launched by separate launch documents (LD), containing the composition of the PAU. This implies both the anticipatory launch of the PAU into production for a specific product, and the grouping of the PAUs by launch batches for different products in accordance with their common need.
In this case the terms are shortened due to the launch of the assemblies and aggregates into production as the DD is ready, without waiting for the readiness of the DD for the product as a whole. The product manufacturing process is optimized, since PAU compositions, grouped by launch batches and by manufacturing shops, are sent into production.
To organize a batch launch, the planning of launch batches of PAUs takes place as early as at the stage of design engineering, together with the specialists of the Planning and Dispatching Department (PDD). At the stage of creating LD, the sequence and composition of launch batches are planned, determined by the composition of PAU’s LD. A preliminary study of the need in material and labour resources takes place, the possibility of purchasing the relevant components is studied, the economic feasibility of manufacturing or purchasing of existing analogues on the market is evaluated, the work of services on the preparation of production of specific products or a range of products begins. In the future, all changes are constantly monitored in the general information space of PAU planning and manufacturing. Accounting of all technological and production operations for each item is ensured.
Such organization of the production process requires effective interaction of all services and departments of the enterprise in a single information space.
At the batch launch of DD into production, traditional general machine building production planning systems using the methodology of detailed planning (MRP II) cannot be applied, since at the moment of plan calculation for the production order (PO) there is no complete data on the design and technological composition of the PO and, accordingly, the product itself.
In order to ensure the possibility of operational management and production plan calculation at the batch launch of the work order into production, the APS (Advanced Planning & Scheduling) methodology is applicable – the advanced synchronous planning taking into account all production resource constraints.
This methodology, along with its basic functions of organizing production and supply chains, should provide the solution of the following set of tasks:
– the maintenance of the list-schedule of LD release;
– the configuration of the current composition of PAU’s LD at the initial launch into production and management of changes in the production of a particular specimen of the product;
– defining the nomenclature of materials and their quantity assessment, necessary to build a single product or batch of products;
– the determination of manufacturing routes (shop-to-shop routing) of parts and assemblies (PAU) together with tentative estimates of labour intensity of manufacturing by the types of production (shops and types of works);
– the determination of the nomenclature of PAU manufactured by cooperation;
-the determination of the necessary means of non-standard technological equipment (STE) for the production of a batch or a single item;
– the preparation of technological data of directive character for the stage “Development of technological processes of PAU manufacturing”. This can be, for example, the dimensions of the workpiece, the requirement to replace the material (if necessary), technical requirements for PAU manufacturing, a list of necessary technological samples and their characteristics.
Thus, the implementation of the considered task allows to provide the logistics services (DMTS and CD) with:
– the approximate data on the nomenclature and volume of the procurement of materials, finished products and components required for the production of a batch of products;
– the preparation of data to the Planning and Control Department (PCD), necessary for planning production resource loading.
This approach, based on the use of approximate data, can reduce the timing of the procurement of necessary materials, significantly reduce the timing of technical preparation and planning of the manufacture of products, preparation and manufacture of necessary equipment.
LD accounting card
Report on PAU elaboration
The implementation of this methodology at the enterprise requires the integration of all the information resources of the enterprise into a single system of electronic paperless production. Taking into account the development of modern software tools, this task is solved with the help of Web-technologies, which provide the joint work of heterogeneous systems and data arrays.
The corporate Web-environment is formed by a set of the servers providing a complex of the procedures, functions and services closely cooperating with each other by means of Web-protocols, XML, etc. This environment, being in essence, the information bus, integrates the work of the services of the enterprise (or enterprises) in accordance with their role in the life cycle of the product. Various automated systems and databases (e.g., PDM Search, TeamCentre, dBase-oriented DBMS) used in the relevant services, as well as the information accumulated in them, are integrated in this information environment and continue to function in the context of the tasks they solve. Built on this principle, the management system does not destroy existing production business processes at the enterprise, but allows to upgrade them as the production is optimized and technologies are developed. This makes the system implementation process less painful – both for the personnel and for the production program of the enterprise.
The input information for such a control system is the electronically created launch document per product batch, the electronic structure of the product within the launch document, and the corresponding reference information that defines the production resources. The environment accumulates an up-to-date knowledge base of all the stages of product manufacturing and is capable of giving recommendations and correcting user actions on the basis of the information it contains.
It is sufficient to use standard web-browsers for the work. Access to the information is provided according to the established “take” and “give” rights in relation to the actual project data for all services of the enterprise.
The creation of a unified web environment for managing the production processes and data of an enterprise makes it possible to effectively implement the mechanisms of “batch” launching DD into production and APS-planning technologies, which is necessary to reduce the time for bringing new products to the market and increase the efficiency of the enterprise work. Thanks to the development of information technologies and knowledge accumulated by specialists, the implementation of such solutions has become possible today at economically advantageous time and financial conditions.
The described methodology is implemented in the systems “APS-Enterprise” and “APS-InfoSfera”, which provide functioning of the paperless information production without disrupting the existing business processes at the enterprise.
Currently, such approaches to the organization of production are gradually being introduced in the enterprises of Ukraine.
The development of this process allows to increase the efficiency of production relations within the enterprise and expands the possibility of interaction in the implementation of common projects.
А.G. Paramonov (JSC“Arkada”), А.V. Petrenko (LLC “А-Prosystem”), N.А. Lyashenko (SE “Antonov”)