Common problems and analysis of blow molding machine (1)
1. What are the requirements of the equipment for the structure of the preform when blowing a light-weight water bottle, stretching and easily accumulating material? The protection scheme for the bottle mouth (so that the bottle mouth is not deformed), and the linear speed of the preform infiltration and baking in the heating furnace (The wall thickness of the preform is thin and the heating time is short)? Analysis: For lightweight bottles, the stretching ratio between the preform and the bottle body is preferably 1:2.5 (excluding the mouth part), which can effectively solve the problem of the bottle stockpiling problem. The diameter of the bottle body should not be too large, otherwise the bottle body will easily turn white. The bottle mouth needs to increase the cooling effect of air cooling and water cooling. So strictly speaking, if the customer's conditions permit, you can refer to the practice of imported machines and install central air conditioners in the production workshop to keep the ambient temperature of the workshop at normal temperature, so that even if the temperature of the chiller is 10 degrees, No condensation will occur. In fact, whether it is a semi-automatic machine or a fully automatic machine, the heating furnace has always been the strength of our national pearl. The heating effect of the heating furnace is the primary condition of the entire blowing process, and it cannot be considered dead grass and leaves no room for it. Whether the process range is large or not, whether it is well adjusted or not is directly related to the heating furnace. The best heating effect should be: heating——blow penetration——heating——blow penetration——heating (series of cycles). Generally speaking, the effective heating time of water bottles should be no less than 27 seconds; the effective heating time of lightweight bottles should be no less than 24 seconds. Analysis: As long as the equipment is controlled strictly according to the method in the instruction manual, and the performance of each safety door is checked regularly, the equipment is generally safe. However, the biggest hidden danger of the equipment is mainly on the seals of the water jacket and air jacket. 2. Blowing a medium temperature bottle, the weight is heavy, the wall of the preform is thick and the heating time is long, the heating furnace needs to increase the heating area, what is the linear speed of the preform infiltration and baking in the heating furnace? The cold blowing process, the temperature resistance of the bottle If the mold heat transfer oil is used for heating, and the cold blowing process is still used, how is the temperature resistance of the bottle? What are the disadvantages, and whether the parameters of the bottle are qualified? Warm water or cold water for the bottom mold is good? Analysis: The effective heating time for medium temperature bottles and hot filling bottles should be no less than 33 seconds. The output of 24,000 bottles/hour should be equipped with a heating furnace with nine zones. Under normal circumstances, if the gram weight of the medium temperature bottle meets the requirements, it can be blown by the cold filling process. Only when the gram weight is light, the negative pressure plate will rise out after filling with warm water due to the insufficient strength of the bottle (the shape of the bottle is more serious, so the bottle shape is best to be a round bottle), will the mold body heating process be considered. Improve the heat resistance and strength of the bottle body. As for the choice of heating method, since the maximum temperature of water is only 100 degrees, a one-step approach can be adopted, and it is recommended to choose a better oil temperature. The bottom of the mold only needs to pass frozen water. 3. When blowing carbonated bottles, how much larger the cold water in the bottom mold needs to be than the water blowing bottle? In order to ensure that the stress at the bottom of the bottle is qualified, what is the cooling time and temperature requirements? How much will the speed be reduced? Adding several heaters is a reasonable structure? Analysis: Since the gram weight of the carbonic acid bottle is heavier than that of the water bottle, the thickness of the bottom of the bottle also has strict requirements, which is thicker than the bottom of the water bottle, generally about 2.4MM, so the carbonic acid bottom is thicker than the bottom of the water bottle. The temperature will be higher than the temperature of the bottom of the water bottle, which must require the chiller to take away more heat in an instant. Therefore, under the same production capacity, the chiller equipped with the carbonated bottle is about 5 horses larger than the chiller equipped with the water bottle. A simpler algorithm can be calculated according to 1200 bottles/horse, for example: 36000 bottles/hour can be equipped with a 30-horse chiller. In order to ensure the stress requirements of the bottom of the carbonic acid bottle, the cooling time is generally 1.2 seconds, and the temperature of the bottom mold is 11 degrees. The number of lamp zones equipped with the heating furnace can refer to the configuration of the hot filling machine, and the effective heating time of the preform should be no less than 33 seconds. 4. Blowing hot filling bottle, the bottle mouth is non-crystalline, what is the upper limit of bottle temperature resistance? The requirements of gram weight? The arrangement of the process time, if the single cavity is designed according to 1600-1700, how to allocate the rotation process time, and how to ensure each The process time required for each angle? Requirements and methods to ensure the cooling temperature of the compressed air? Analysis: At present, the preform mouths used in the production of hot-filled bottles in the industry are generally divided into crystalline mouths and non-crystalline mouths. Divided into 28 and 38 two. As far as the bottle mouth is concerned, the crystalline mouth can withstand 100 degrees without deformation, but the upper limit of heat resistance of the amorphous mouth is only 92 degrees. If it is higher, the bottle mouth will be deformed by heat.