Workpiece
As a semi-finished product is generally starting material so designated, prefabricated raw material and workpieces or semi-finished products of the simplest form. They usually consist of a single material that has only been brought into a basic geometric shape.
Semi-finished products are, for example, simple profiles ( profile steel , construction profiles ), rods , tubes and plates made of metal (→ semi-finished metal ) , plastic (→ semi-finished plastic ) or wood .
Workpieces that have already received an individual shape in a preparatory production step, but are still intended for further production steps, are also referred to as blanks .
In manufacturing technology , metal materials are usually delivered as semi-finished products. Over 1000 types of semi-finished products made of metals and plastics are standardized in terms of material and surface quality, shape and dimensions as well as manufacturing tolerances .
Semi-finished products as a term in the accounting sense are on the assets side of a company's balance sheet and are part of current assets .
Properties and delineation
Metallic semi-finished products are usually not created directly through casting or other primary forming processes , but in a second step through forming or cutting processes such as machining .
In the next step a semifinished product is either a finished part , or first to a further semi-finished product processed .
Raw materials such as B. bulk goods , granulates , powder, liquids or gases are not counted as semi-finished products because, unlike semi-finished products, they are not geometrically determined, solid bodies and the product has not yet been "semi-finished".
Prepared components , prefabricated components (eg. Structural profiles ), prefabricated blocks, modules are also not included among the semi-finished products, as these are widely used in the original design and therefore - at least in relation to the material processing - as a kind of provisional end products are considered, although assembly processes and processes of fitting can follow for these.
Significance in manufacturing technology
As “semi-finished material”, semi-finished products represent an important element of efficient and cost-effective production. They are usually designed in such a way that their shape and dimensions correspond as closely as possible to the product to be manufactured. The material and surface qualities are often optimized for specific purposes and manufacturing processes. There are, for example, semi-finished aluminum products that are particularly suitable for welding or steel sheets that are designed for deep drawing . The magnetic properties of electrical steel are specially designed for use as iron cores in transformers, motors and generators. Since around 75% of the tinplate produced is used for the production of tins and drinks cans, its material properties are usually specially designed for this use.
literature
- Martin Creutzig: New wholesale business apprenticeship . Peter Lang - International Science Publishing House, Frankfurt a. M. 2009, ISBN 978-3631-59082-9 .
- José Luis Moro: Building Construction - From Principle to Detail , Volume 2 Concept. Verlag Springer, Berlin 2008, ISBN 978-3540-27790-3 .
- Emil Larek: Business Mathematics . Frank & Timme GmbH - Publishing House for Scientific Literature, Berlin 2012, ISBN 978-3865-96480-9 .
Web links
- Illustration of a warehouse for semi-finished products at Bielefeld University
Individual evidence
- ↑ Ulrich Kurz, Hans Hintzen, Hans Laufenberg: Constructing, shaping, drafting . Vieweg & Teubner-GWV Fachverlage GmbH, Wiesbaden 2009, ISBN 978-3-8348-0219-4 , p. 320.