Linear or branched chain structures, which consist of repeating monomers are called thermoplast (also known as thermoplastic).
They can be softened and re-hardened infinite times.
Reheating temperature should not exceed a material specific maximum, as it will cause degradation of the polymers.
Typical examples of thermoplastic materials include PA, PE, PC and PVC.
Thermoplastics can be subdivided into two distinct classes: Semi-crystalline and Amorphous.
Multi-functional Polymers with the processability of thermoplasts and the elasticity of vulcanized rubbers are called TPEs (thermoplast elastomers, also known as, thermoplastic elastomers).
Like thermoplasts, it is possible to repeatedly heat them up for softening and cool them down for hardening.
TPE is used for bathmats, housing (soft grip), handles, etc.
Typical TPE-Classes are: S-TPE, COPE and TPU.
Polymers that get rigid due to curing are called thermosets.
In this process, molecules will crosslink (purple) themselves and form one single makro-molecule.
Because of very strong covalent bonds, the makro-molecule can not be melted again.
Even if high heat is applied, the only result will be degradation.
In contrast to a thermoplast material, the mold for thermoset materials is heated up.
Typical thermoset polymers are phenolics, epoxies and resins.
In printing processes, such as pad printing, an additional thinner (solvent) is added to the printing varnish. The addition of a thinner does not just influence the viscosity and ink dispensing behaviour of the pad printing ink from the pad to the workpiece, but it also has a very particular influence on the drying speed. By adding a thinner, the printing process can therefore be optimally adjusted to the specific local conditions.
External threads can be checked with the help of thread ring gauges.
With a GO thread ring gauge the flank diameter and the pitch deviation of a sample are measured.
Furthermore the core diameter can be tested. It is therefore a dimension gauge and a form gauge.
The testing sample needs to be screwed completely into the GO thread ring gauge without any particular extertion of force.
If this is not the case, the tolerances of the nominal dimension are not fulfilled.
A NOGO thread ring gauge is used to measure the falling below the specified minimum dimension of the flank diameter.
The NOGO thread ring gauge never fits on a perfect test sample. It is therefore only a dimensional gauge.
The reject (NOGO) side of the ring gauge is marked with red.
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