The cold runner and hot runner use different injection systems in the plastic injection molding process,and they generally do not share the same pipeline.Below,I will further explain the working principles of cold and hot channels and the differences between them.

　　1.Cold runner:

　　Cold runner is a traditional injection molding system that uses cooled and melted plastic.After the plastic is injected into the mold,the cold runner enters through the injection nozzle and mold cavity,and then cools and solidifies in the mold.The plastic in the cold channel will solidify after the injection process,forming a cold channel shape,so there is no continuous heat supply.Due to the cooling and curing characteristics of plastics,cold runner systems typically require regular cleaning and maintenance.

　　2.Hot runner:

　　Hot runner is an advanced injection molding system that maintains thermoplastic materials in a molten state by setting heating elements in the mold.The hot runner system consists of a hot plate,a hot runner pipeline,and a hot runner needle valve.The hot runner system uses heating elements to provide continuous heat energy between the runner and the mold cavity to ensure that the plastic remains in a molten state.The temperature control of the hot runner system can make the plastic flow more stable during the injection process and reduce or eliminate defects at the injection points.Cold runner and hot runner

　　From the above principles,it can be seen that the cold runner and hot runner use different injection systems and working principles.The cold runner mainly relies on the cooling and solidification of plastic to achieve molding,while the hot runner relies on heating elements to maintain the melting state of plastic and control its injection flow.Therefore,there are differences in their injection process,component design,and operation methods.

　　In actual production,some complex injection molds may include both cold and hot runner systems to fully utilize their respective advantages.In this case,the hot and cold runners are usually arranged separately in different parts of the mold,each used separately rather than sharing a common pipeline.The use of different systems can better meet the needs of specific products and processing processes,improve production efficiency and product quality.

　　It should be noted that selecting an appropriate injection system and designing a reasonable mold structure are determined based on specific production needs,product characteristics,and economic considerations.Therefore,in the process of mold design and selection,it is necessary to comprehensively consider factors such as production requirements,cost-effectiveness,and processing complexity to meet production needs to a large extent.