1. Low ambient temperature
Due to their chemical structures, plastics become brittle at temperatures around freezing point.
They become hard, inelastic and sensitive to impact. A low ambient temperature increases the risk of breakage and cracking due to external forces, especially in the case of finished parts. It should therefore never be thrown, shaken or dropped.
2. Weathering factors
Weathering factors such as solar radiation, atmospheric oxygen and humidity can change the material properties of plastics and have a lasting negative effect. Of plastics and have a lasting negative effect (e.g. by fading and/or oxidation of the surface of materials without special
of materials without special UV stabilizers, water absorption, etc.). Direct exposure to sunlight or one-sided heating can lead to permanent warpage or waviness due to thermal expansion and residual internal stress. For this reason, finished parts should never be stored in the open air, and semi-finished products, if possible stored in the open air. The scratch-sensitive surfaces of plastics require special attention during transport and storage.
3. Plastic surfaces
The scratch-sensitive surfaces of plastics require special attention during transport and storage. They may have sharp edges
on shelves, nails in pallets, coarse dirt particles between products and other sharp-edged objects can cause scratches and/or scores and possibly breakage due to the notching effect.
4. Contact with chemicals, solvents, oils, greases
The wide variety of material compositions of plastics means that their resistance to chemicals, solvents, oils and greases varies,
oils and greases. Contact with these substances can lead to surface clouding, swelling, decomposition and lasting changes in mechanical properties. These chemically aggressive substances should always be stored in a secured place and not in the vicinity of plastics.
5. temperature fluctuations
Major temperature fluctuations can lead to reversible dimensional changes in plastics due to shrinkage or elongation. For this reason, dimensional checks should only be carried out immediately after receipt of the goods if the products in the delivery state
room temperature (20°c). Since temperatures above or below room temperature can lead to expansion or shrinkage of the material and thus to incorrect measured values, the material should be stored temporarily in a dry place and brought to room temperature before a dimensional check is carried out.
6. Residual stresses
Despite annealing, plastics and the finished parts made from them may exhibit residual stresses due to their special manufacturing process.These tend to relax during longer-term storage under the influence of temperature (e.g. solar radiation).
The additional tendency of polyamides to absorb water at elevated humidity levels leads to an increase in volume.
Both processes usually involve dimensional changes and warpage. For these reasons and despite all care taken during the manufacture of our products, we cannot guarantee permanent dimensional accuracy and freedom from warpage of finished parts.