Seven Tips for Quick Mold Change System of Production Line

SMED, Single Minute Exchange of Die, "One minute instant mold change", we generally call it Quick Mold Change, also known as quick production change, which is a fast and effective method of job switching.

Quick Mold Change System is a method used to continuously improve the difficulty of rapid adjustment of equipment, shorten the line change time as much as possible, and even achieve instant line change. It can quickly switch an ongoing production process to the next production process. The main purpose and benefit of the quick mold change system is to reduce the time waste of work operation and the number of work-in-progress, thereby increasing the number of switching times, achieving small batch production, increasing flow rate and shortening production cycle, and meeting customer requirements without additional inventory. There are several tips in the Quick Mold Change System that we should pay attention to.

1. Parallel operation

The so-called parallel operation refers to two or more people working together on the switching action. Parallel operation can shorten the effect of operation time. It may take one hour for one person to slowly engage in the switching action. If two people can work together, it may be completed in 40 minutes or 20 minutes. Then the entire switching time is reduced from the original 1 hour to between 20 minutes and 40 minutes. The labor time required for parallel operation may increase, remain unchanged, or decrease, which is not the focus to be considered. Because the other effects obtained by shortening the switching time are far greater than the labor cost, this point is more likely to be overlooked. When engaging in parallel operations, the coordination between the two people must be practiced and proficient, and special attention must be paid to safety, and no accidental injuries should be caused due to negligence.

2. Do not move your feet

‘The switching action is mainly completed by the action of the hands, and the feet must reduce the chance of moving or walking. Therefore, the props, molds, cleaning, etc. that must be used during the switching must be placed on a special trolley and arranged in order. When we switch the action sequence during Quick Mold Change, we must rationalize and standardize it.

3. Special props

Props are special tools made for special purposes. When we switch actions, we should use props instead of tools as much as possible, because props can improve the efficiency of switching and shorten the switching time. In addition, the instruments we use for measurement should also be instrumentalized, using block gauges or grid bars instead of measuring with rulers or readings of meters. The most important point is to try to reduce the types of instruments to reduce the time for searching and taking and putting.

4. Eliminate screws

When switching actions, screws are the most common method used to fix molds. There is certainly a need to use screws, but the action of installing and removing screws usually takes up a lot of switching time. If you observe carefully, you will find that there are too many places where screws are abused. For example, only four screws are needed, but six are used. Too many turns of screwing are also time-consuming. The function of tightening screws is only in the last turn. Therefore, we need to eliminate the fixing method of screws. For example, latches, pressure rods, intermediate clamps, card sockets, shaft cam locks, positioning plates, etc. can be used to replace the use of screws.

5. One turn is fixed

When bolts and screws must still be used due to some special circumstances, we should also try to reduce the time of tightening and removing screws. The goal of improvement is to achieve the locking function without removing the bolts and screws. The main method is to tighten or loosen it by rotating it once.

6. Standardization

The switching action is because different products require different molds or working conditions. Therefore, adjustment actions must be made and new standard operating methods must be set. The adjustment action takes about 50%-70% of the entire switching time, and the length of the adjustment time varies greatly. When you are lucky, you can adjust it all at once, but when you are unlucky, it takes dozens of minutes or even hours. It is also common to see that for the adjustment action, it is a waste to have to make adjustments first. The goal of improvement is to eliminate the adjustment hole.

7. Preparation in Advance

Preparation in advance is an external operation. If the external operation is not done well, it will affect the smooth progress of the internal operation and make the switching time longer. For example, if the external operation is not fully prepared, when the internal operation cannot find the required props or the mold is wrong or defective, it is necessary to temporarily stop to find the props or repair the mold, which will cause the Quick Mold Change System operation time to be longer.