1A Sheet Metal Tensile Test Grinding Machine PSM2000

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

options:

• Protective hood over the grinding room (not required for CE marking)
• Semi-automatic operation through oscillating sample table
• electric countercurrent braking of the motor

The non-plus-ultra: PSM2000 sample grinding machine 2000 (grinding belt length 2000 mm): With industrial-grade grinding belts and a grinding belt 2.000 x 100 mm (area 2.000 cm²) up to 600 tensile samples can be ground. The grinding belt is used across the entire width. We are increasingly receiving feedback that with the competitor's product (especially with hard materials) the sample is "guaranteed" to tear outside the measuring length = the sample has to be discarded (and the same problem occurs again with the next tensile test...). No other type of finishing meets the requirements of the material testing and thus the standard. ISO 6892 better.

• Removal of edge damage after punching (removal of the work-hardened edge zone)
• Removing the melt edge after laser cutting the sample (common in press hardening)
• Post-processing of the unclean/conical cutting edge after waterjet cutting
• without cooling water (!): No time-consuming and costly disposal of metal sludge
• Extraction not required: Grinding is done with grain 80 – no health risk even with stainless steel
• low sample heating (temperatures below 65 degrees, cooling NOT required)
• In total, approximately > 5.000.000 tensile specimens were ground on our machines – without any complaints.
  Compared to competitor machines, the grinding belt surface (13,3 cm²) is 2.000 times larger for up to 600 tensile samples
• Utilization of the entire sanding belt width (competitor machines have no oscillation and cut the belt in one place or use it only in one place / premature destruction)
• This machine is the favorite of ALL our customers in terms of handling, accuracy, stability and consumption costs; 
• Customer opinions on competitor machines: “Inaccurate, returned, shut down, not suitable for industrial use, complex metal sludge disposal, high consumption costs for grinding belts.” It is often underestimated that a sample must be reworked after punching / lasering. However, this is clearly regulated in standards (including ISO 6892). See
• Knowledge Manufacturing Tensile Specimens from Sheet Metal
• Specification of the standards: “The production of these samples by shear cutting (punching) can lead to significant changes in the material properties, especially the yield strength (due to work hardening). Materials that harden strongly should always be produced by milling, grinding, etc.