Interpretation of professional terminology of positive and negative pressure machine-8 times, including: heating time, operating cycle, negative pressure time, positive pressure time, setting time, blow-off time, delay time, film feeding time, etc.
1. Heating time. It is the time that the sheet stays in the electric furnace. Generally, the forming machine uses three-stage heating. For example, if the operation cycle is 3 seconds, the sheet must stop three times from entering the electric furnace to exiting the electric furnace. Each heating is 3 seconds, then the total time That's 9 seconds. The length of the heating time depends on the material and thickness of the sheet, the temperature of the electric furnace and the operating cycle time. Generally speaking, the thicker the sheet, the longer the heating time is. The higher the temperature of the electric furnace, the shorter the heating time. In actual production, in order to increase production capacity, the commissioning principle is to use a higher heating temperature to shorten the heating time, thereby speeding up the operation cycle time and reaching the production capacity of the equipment.
2. Operating cycle. It refers to the total time of mold closing, positive and negative pressure forming, cooling and shaping, blowing out of the mold, and sending out of the chain. Generally, the operating cycle of machinery can be very fast, which is shorter than the heating time. Therefore, when the heating time cannot be shortened, the operating cycle time is equivalent to the heating time.
3. Negative pressure time. It refers to the length of time from the beginning of vacuuming to the end of vacuuming after the mold is closed. Because mold closing has a time course, vacuuming generally requires a delay. In principle, the negative pressure time should be as long as possible, which is conducive to the close contact of the sheet to the mold and the rapid cooling and shaping of the product.
4. Positive pressure time. Compressed air is much larger than vacuum pressure, so positive pressure is more conducive to product molding, which indirectly reduces the heating temperature, reduces the burden of cooling water, and does not affect the heating time of the sheet. Generally, the start time of positive pressure is later than the time of negative pressure, and the end time is earlier than the time of negative pressure, which plays the role of high pressure forming, shaping and cooling in the middle.
5. Setting time. It refers to the time for the product to be cooled and set in the mold after being formed by positive and negative pressure in the mold. The length of the setting time depends on the temperature of the mold, the size and thickness of the product. To obtain a qualified product, cooling and setting play a key role. Generally, the time should not be too short. Lower cooling water temperature can shorten the setting time of the product, but too low mold temperature will also cause the product to shrink too quickly and produce cooling marks, so reasonable mold temperature control is particularly important.
6. Blow away time. Also called air ejection time. When the mold is opened, the vacuum is quickly switched to positive pressure to break the vacuum, and it will also give the product a back-blowing force through the vent hole, which can prevent mold sticking and help product demolding.
7. Delay time. All the actions of the multi-station are based on the stop and stop of the chain. By setting the delay time of each action, there will be a sequence of morning and evening, and a good action can be coordinated to obtain a good product.
8. Delivery time. It is the time for the chain to move. After the first mold is completed, the chain drives the sheet to the next mold, and it starts and ends again and again. It is the beginning and end of the running cycle. The length of the feeding time depends on the length of the mold width, the faster the chain speed, the shorter the feeding time.
