Pressings have diverse functional characteristics. Some pressings shall be as stiff is possible, others have an esthetic or visual function. Components that have a very simple spring function for single use are also grouped as pressings.
Technical information of Pressings
Pressings is not a homogenous group of components and cannot be characterized by certain functional characteristics.
Some pressings are load carrying components that shall be as stiff is possible, others do not carry load but have instead an esthetic or visual function, for instance lids or covers for electronics. Components that have a very simple spring function and are only used once are also normally grouped as pressings. Examples of this might be clips for the fastening of cables, bushings that are held fixed by the radial force that is needed to fit them into a hole or tensioning washers for bolts.
Pressings are often made from rectangular cross section material in the form of strip or sheet, but can also be made from wire. Virtually everything that can be produced from strip or wire by using the basic manufacturing operations cutting and bending are possible to produce. For smaller volumes, each required cutting and bending operation are made as a separate process, but for larger manufacturing volumes all the required cutting and bending is either integrated into a single progressive tool or made in multi-slide cutting and bending machinery.
Stampings and strip components
There is constant progress in the field of stampings and strip components. Our main competitive advantage is strong technical competence, qualified tool development, low cost production and good service.
We work on design, development and production of components made from steel strip. A wide range of technologies makes it always possible to select the production technology that best suits each individual assignment, irrespective of it is for 10 or 10 million components. We work with a number of different materials in thicknesses from 0.05 – 5 mm.
Our stampings and strip components are made in Sweden, China, Latvia, United Kingdom and Denmark. It is important for us to be involved right from the start of a customer project. If we are involved right from the start, we are more able to influence the choice of quality, optimise the function and to keep the costs down.
The most important decisions when you use stampings are made at the beginning of the project. Detailed design, including the choice of the right material and surface treatment, have a large influence on both production price and quality.
Lesjöfors has the deep knowledge and experience needed, of spring materials and their properties. We also have experience and knowledge of the way that the tools for stampings should be designed and made.
Prototype springs and samples
We produce prototype springs and technical samples, as a natural part of the development of a new product in collaboration with our customers. This is the customer’s guarantee of getting a quality product that meets expectations. Lesjöfors can quickly produce small batches of stampings and strip components for technical samples or prototype springs. This work is done in our tool department, using stamping tools, laser cutting, water cutting and spark erosion etc.
Specific tools and stamping tools
Specific tools for a project are designed in house. We have our own toolmakers who make the tools we use in production. There is also a wide network of external subcontractors who specialise in design and manufacture of stamping tools. We look after to maintenance ourselves.
A wide range of technologies makes it possible to choose the production technology that best suits each assignment, irrespective of the quantity involved is 10 or 10 million strip components. Lesjöfors offers two main types of production processes; automatic and manual production. Automatic production involves multislide machines supplied by companies such as Bihler or Finzer, eccentric presses and quick stamping tools such as Bruderer. Manual production involves manual bending and hand stampings of components.
Stampings and press products
Automated production in squencing tools is used for large volumes. The tools used are unique for each product and the machinery is eccentric presses and quick tools for stampings, such as Bruderer, Kaiser, SMV and Raster. It is not unusual for volumes to amount to 10’s of million components a year.
The requirement is frequently not large enough to justify the investment in automated production.
Lesjöfors can also manage these batches in a rational manner by using a production design based on universal, adjustable tools. Lesjöfors’ small batch concept, with the wide choice of material from the stores and the universal machine and tool setup give maximum flexibility at low cost without investment in tools, and thus gives short times.
Multislide machines like Bihler & Finzer are used for complicated bending of stampings and strip components. The tools are unique for each product and give very high capacity, so the multislide technology best suited for high volume products. In this area, we use integrated 100% quality control with vision technology.