Understanding the “relationship between thermal stability of plastics and the permissible length of stay” requires that the physical flow of materials, heat history and equipment be placed on the same chain of causality. The key mechanisms for this topic are: the oxidation, cracking, interconnection or devolvation rate of the material at the processing temperature determines the safe stay time. The material structure, thermal performance and flow base determine the path to plasticization and cannot simply reproduce temperature and velocity by trade name. Therefore, the name of the material and the recommended setting can only be used as a starting point, and the actual judgement is to return to the plate number, water, filling and assistor, the single total quantity, cycle, screw structure and product requirements to confirm whether the temperature, cut and stay of the material in the equipment is safe.

At the test-model or volume-import stage, an input list should be established around “the relationship between thermal stability of plastics and the permitted time of stay”, including feedstock suppliers and batches, technical data sheets, drying conditions, the ratio of colored mothers and respirators, equipment to screw specifications, product and fluid weights, the temperature of moulds and existing defects. The detection sites should cover dryer exports, aircraft-side pyrotechnics, air-launched molten products and products, so as to avoid drawing conclusions only at one point. The main risks to the subject are that prolonged stoppages without cooling or too small a quantity of materials can trigger yellow changes, black spots, gas and reduced performance. Parameters must be recorded in a specific pattern to distinguish material from equipment from operational changes.

Control methods should not begin with blindly increasing temperature or pressure, but should be based on "substance state - feed drying" The sequence of screw plasticization - nozzles and fluids - product results. Where the defects can be temporarily pressured by extreme temperatures or back pressure, it is more important to confirm the existence of structural, water-bearing, pollution or gaping problems. The site adjusts only one main variable at a time, while observing the actual melting temperature, measuring time, screw twists, mats, injection pressure, product weight, colour, scent and critical dimensions. If production can only be sustained by extreme parameters, the use of a switch to cover the material or hardware boundary should be discontinued.

The “relationship between thermal stability of plastics and the permitted duration of stay” suggests a repetitious approach: time-suspension tests are performed to record changes in colour, scent, viscosity, pressure and mechanics. For material at risk of degradation, a stop-time gradient sample is also maintained to compare colour, scent, viscosity and mechanics. The technical agreement between the supplier and the plant shall state the material, the sampling method, the detection project, the permitted scope and the change notification requirements. The plasticization programme can only be considered to have long-term quantitative value if the product ' s probabilities, performance, cyclicality, energy consumption and maintenance costs are met in a continuous production process.