Product prices of plastic molded products are roughly divided into material costs, processing costs, sales management costs, profits and so on. It is the processing cost that the molding cycle affects the product price. The cost of plastic molded products is calculated by multiplying the processing cost per second and the processing cost per minute by the molding cycle to obtain the processing cost, and then considering the cost of plastic injection molded products. If the molding cycle is shortened, the cost of molding processing can be reduced, and the cost of products will also be reduced. Reducing the molding cycle of plastic injection molded products is very important when considering product costs.
As a method of shortening the molding cycle, we will start from the point that does not directly affect the quality of plastic injection molded products. If molding conditions have already been set, since injection conditions, plasticizing conditions, cooling time, etc. will affect the quality of the molded product, we will analyze the other processes and review the conditions firstly.

1．Time difference between processes operating simultaneously

• After opening the mold, does it take time to prepare the unloader for operation?
• Is it taking time for either the product removal or runner removal?

2．Is there no time when nothing is working

• Time from completion of mold clamping to start of injection (filling delay time)
• Protruding start time after mold opening is completed
• After product removal, mold closing start time

3．Speed of each process

• Mold opening / closing speed
• Protruding speed
• Operating speed of unloader

If the wasted time can be reduced, the molding cycle can be shortened. Although the molding conditions are not changed, the mold temperature may increase due to the shortening of the cycle, so the product dimensions may change. When checking the quality of plastic molded products, it is important to check that the mold temperature is stable for a quality check.