Assembly line
The assembly line is a form of flow production and is primarily known from the automotive industry.
Building an assembly line
In an assembly line, the different variants of a product are manufactured through successive assembly activities. For the ongoing assembly, a mounting support is required on which the assembly object is fixed. The basic assembly object i. d. Usually a static element of the product to be manufactured in question; this can be a mounting plate, a subframe or - as in automobile construction - a body. The sequence of the assembly steps is not arbitrary, but requires a certain sequence that must be planned precisely in advance . The assembly line is divided into assembly cycles. The assembly object runs through the cycles in a certain cycle time . During this time, the assigned assembly activities must be carried out, which are precisely described in a work plan or work instruction in which all required tools and aids as well as the parts, assemblies, etc. to be installed are precisely specified.
Assembly-compatible construction
A product and its different variants to be able to one and produce the same assembly line, an assembly requirements is construction of product required. To this end, the component and assembly variants should be interchangeable as far as possible. The technical connection points and the connection technology between the different units, parts and assemblies and their variants should be standardized as far as possible. (see also in: product design and modularity )
history
Assembly production began in the automotive industry with the "progressive assembly line" by Ransom Eli Olds , in which the body was attached to a moving carriage that was pushed from workstation to workstation. Henry Ford developed this principle together with his engineer Sörensen and his foreman Lewis to create the "moving assembly line". As a result, the production costs of his Ford T-model could be drastically reduced and the sales price lowered. The assembly production was then taken over by all automobile manufacturers. In recent years, this form of flow production has also established itself in other branches of industry with complex and varied products, such as aircraft construction, mechanical engineering or the electrical industry.
Control of assembly lines
The control of the assembly and assembly lines is of great importance for complex and varied products, as these more and more different product versions are assembled on one assembly line. Due to the technical complexity also be in vehicle large aggregates such as engines, transmissions, axles or seats, either even produced on separate assembly lines or in separate assembly plants. Extensive assemblies of components such as the cockpit , the front end, the vehicle doors, the sliding roof or the drive train are moved to pre- assemblies and / or to a supplier. The pre-assembled units or assemblies are then completely built into the final product on the final assembly line. In the case of high production quantities, several assembly lines may be required in a production plant. The vehicles must then be allocated to the assembly lines, taking into account any existing production restrictions. For production planning and control , this results in the task of controlling the sequence and occupancy of the assembly lines as part of the scheduling so that the utilization of employees and production resources is as optimal as possible through leveling .
The greater the differences in the equipment of the vehicle models, the more difficult and ineffective production on a fixed assembly line becomes. As an alternative to the assembly line, Audi announced in November 2016 that it would pack the car bodies on transport trolleys, which should autonomously approach the various production islands for the respective assembly steps required depending on the load. (see also Industry 4.0 )
See also
literature
- Earley & Walkinshaw: Setting the Pace - Oldsmobile's first 100 Years . Oldsmobil Division of GM Verlag, Lansing 1996, ISBN 0-7853-1958-1 .
- H.-P. Wiendahl et al. (Ed.): Mastery of variants in assembly - concept and practice of the flexible final production stage . Springer Verlag, Berlin 2004, ISBN 3-540-14042-5 .
- W. Herlyn: PPS in automobile construction - production program planning and control of vehicles and assemblies. Hanser Verlag, Munich 2012, ISBN 978-3-446-41370-2 .
- W. Holle: Computer-aided assembly planning - assembly planning and simultaneous engineering. Hanser Verlag, Munich / Vienna 2002, ISBN 3-446-21986-2 .
Individual evidence
- ^ W. Herlyn: PPS in automobile construction. Hanser Verlag, Munich 2012, p. 24 ff.
- ^ W. Herlyn: PPS in automobile construction. 2012, p. 217 ff.
- ↑ Audi wants to abolish the assembly line. In: Wirtschaftswoche. November 26, 2016. Retrieved November 27, 2016 .