Indispensable for punched / laser cut tensile specimens

The best, gold-plated Tensile testing machine in the world can only deliver results as accurate as the sample allows. The demand for accurate results / meeting the quality requirements of the standards requires flawless sample preparation!

Punching is the most efficient and therefore most economical way to take a tensile test sample from a sheet metal, provided that the work-hardened edge zone of the sample can be removed cleanly and efficiently. This can be done by milling or grinding in accordance with standards (see picture above: PSM2000 sample grinding machine).

Sample production by laser cutting: For difficult-to-punch sheets (strengths >1600 or >1800 MPa: For hardened sheets from press hardening / hard-rolled sheets / special alloys), the tensile specimen can alternatively be cut using laser cutting. However, it is very important to remove the melting edge or the entire heat-affected zone. This preparatory work (production of the tensile specimen / dumbbell) is usually carried out in the laser cutting / trimming production area. The tensile specimen (with melting edge) is then ground using the PSM2000 specimen grinding machine.

Other types of sample preparation (usually unsuitable)

Materials / types of steel that cannot be milled: According to customer statements, the following types of steel cannot be milled at all. This is mainly because the milling technology fails and even first-class milling cutters become blunt "immediately" (when used for the first time - the cutter no longer cuts; the material is compacted and the result is therefore distorted): DUPLEX steels / steel key material numbers: 1.4376 H500 - H800 - H1000 | 1.4378 | 1.4462 | 1.4162 | 1.4419 | 1.4122 | 1.4618 | 1.43XX (with manganese alloy) | 1.4301 (with manganese alloy) hardened steel for press hardening / hot forming, especially "manganese steel".

The sample grinding machine, which has been around since 1970, is now so sophisticated and structurally improved that even semi-skilled workers are able to produce absolutely parallel samples with a high surface quality in the shortest possible time - with a guaranteed sample parallelism of better than 0,02 mm (IDDRG recommendation). The sample grinding machine is constantly being further developed and is known for its robustness. Innovations over the years: 

Belt tensioning via pneumatic cylinder (increased comfort when changing sanding belts and reproducible clamping pressure with improved reproducibility of the sanding results).

new maintenance-free parallel guide

new sample holder via pins – less sensitive to contamination of the contact surfaces

new tape direction correction

closed machine room below: grinding dust no longer falls to the floor

digital display of zero position and feed (grinding removal)

increased safety: door lock when sanding belt is running