Common POM sheet and POM Rod experience significant temperature differences between the surface and core during cooling, leading to internal stress. This stress increases with sheet thickness and rod diameter. If this internal stress is not effectively released, the machined product will deform considerably, and in severe cases, may even crack.
We have identified the optimal critical temperature for heat treatment of Polyacetal Sheet and Polyacetal Rod, as well as the relationship between temperature and time, through reverse simulation of the stress generation process. This principle also applies to other thermoplastic rods and sheets. Each batch of POM sheet (also called Delrin Sheet) and rod produced by Anheda undergoes a stress-relieving treatment of over 100 hours.
When processing POM sheets and rods, our internal stress removal method (annealing) involves annealing before processing.
The general annealing steps for POM products are as follows:
1. Turn on the power to the electric oven;
2. Set the temperature control knob to 160℃;
3. After reaching the set temperature, place the product inside the oven;
4. The holding time increases with the thickness of the workpiece. Specific details can be found in the product's technical documentation. Engineers calculate the holding time by multiplying the workpiece thickness (measured at the thickest point of the workpiece wall in mm) by 5 minutes per 1 mm, rounding up to the nearest 1 mm. For example, if the workpiece thickness is 10.5 mm, the holding time = 30 + 11 * 5 = 85 minutes. And so on.
5. Open the oven door, remove the product, and allow it to cool to room temperature.
Anheda specializes in producing POM sheets, anti-static POM sheets, extruded POM, high-temperature resistant POM, POM rods, POM+GF, and other related POM products. Welcome to contact us.
AHD POM Polyoxymethylene Rod
