The hottest hot runner system for prolonging the s

2022-10-24
  • Detail

Cavaform international has more than 40 years of production and operation history in manufacturing precision injection molds and mold parts. The company has won wide praise in the medical market, especially in the catheter die and the multi cavity high tolerance die for the production of disposable medical supplies. The molds provided by the company reflect a development trend in the medical field in the early stage when people use cloth bags to dress and eat food

according to chuck massie, general manager of the company, cavaform international has sold 1million sets of mold cavities and other mold parts worldwide, 75% of which are injection molds. The biggest business of the company is disposable medical supplies. The other three major businesses include stationery market, cosmetics packaging and traditional packaging

molds for disposable medical supplies manufactured by cavaform international are generally multi cavity molds (32, 64 ~ 196 cavities), and some molds can produce millions of products every day. The characteristic of these products is that once the design is finalized, it will not be easily changed. Because the output of these products is very large, the parts of the mold need to be easily disassembled and replaced, and hot runner needs to be used to reduce waste or recycled materials

medical products shapers and OEMs will not have a lot of inventory, so processors must have the ability to produce quickly to avoid delivery delays. Cavaform needs to find a set of hot runner system suitable for these complex molds, so that it can meet the requirements of rapid production. In the process of finding the hot runner system, we need to consider that the system can control the gate and open it synchronously with the gate under low injection pressure and mold core deviation. At the same time, cavaform is looking for multi head nozzles for the production of thin-walled or cylindrical medical supplies

market challenges

obviously, finding a suitable hot runner system that meets the company's standards is a great challenge. The parts themselves must be very accurate and have tight tolerances. Generally, the tolerance must reach 0.5 ‰, which is a very high requirement. To reach this standard, we need to have very precise mechanical equipment, well-trained staff and high requirements for mold measurement and maintenance standards

finding a hot runner solution approved by customers is a difficult task. Now, given the quality requirements, what the company needs to do is to provide a mold with long service life and less maintenance

cavaform international turned to mold masters. This is a hot runner system and parts manufacturing company, which can provide a complete set of hot runner systems. Cavaform international adopts the hot runner provided by mold masters to manufacture the medical supplies mold, which has the advantages of less maintenance and long service life

for multi cavity molds, the use of multi nozzle can effectively reduce the cost of hot runner system and control system, which is very attractive to OEM manufacturers

cavaform International provides customers with value-added services. When encountering problems and downtime, many OEMs hope to get services within 24h or 48h. As a mold manufacturer, coordination with hot runner suppliers is very important. Today, cavaform international stipulates that it will provide all necessary services for all molds manufactured by companies within 48 hours

OEMs in most medical products are produced in real time and will not have too much inventory. Therefore, the molding, transportation and assembly of products require rapid completion. Therefore, if the mold cannot be quickly prepared for use, it will affect the production efficiency. If the hot runner system has problems, mold masters will provide services to solve these problems

melt disk system

Mike Ellis, manager of the marketing department of mold masters, explained that melt disk is an accurate melt transmission system, and the system also integrates die and core inserts. This design will not affect the cavity strength or cooling requirements, nor will it affect the side parts of the cavity, such as ejector pins. At the gate position, the system optimizes the heat control through the heating unit. Therefore, this design is particularly suitable for the production of thin-walled and cylindrical products, such as the processing of pipettes, syringes and other small products, which requires the opening of side gates. The synchronous side gate can produce 2, 4, 6 or 8 parts, and the nozzle tip angles in the horizontal direction are 15 °, 30 °, 45 ° and 60 °

Ellis added that in the multi cavity mold, the key to obtain high yield is: good gate control, open synchronous gate, wide processing window, low injection pressure and small core expansion

melt disk features include: the geometry of melt disk ensures the balance between mechanics and rheology in the design process; The complete gate area thermal control system is independent of the hot runner system; The precision polished nozzle head and gate seal enable all cavities to obtain ideal heat transfer, especially in the processing of medical products. The adaptability and heat control of melt disk make it very suitable for this industry

in the conceptual stage of WIP, the position of gate should be selected well. The filling characteristics of melt should also be fully considered, especially in thick wall products. It is recommended to determine the gate position on the surface of the component, because the product will withstand a certain shear force during the drawing process

application case

cavaform recently manufactured a mold for producing fine needles, which are mainly used in drops. It is reported that the mold has 32 cavities and is installed on a 75t electric injection machine. At first, the customer provided the mold to cavaform company, hoping that the company can pretreat the carton under the standard test state for 24h (generally, carton users can unconditionally go to the authoritative and impartial testing agency for testing) and then retest and transform the mold to manufacture new products. During the test, the company found that the hot runner system of the mold had been damaged, so that the melt could not fill the mold through the gate. Because the original system is designed for the processing of polypropylene, it is not suitable for the processing of polyacrylate materials, and the original hot runner system can not guarantee the temperature (6) cycle torque range/peak relative error and relative repeatability in the gate area. Therefore, cavaform chose melt disk system, which is one of the best solutions to this kind of problem

the mold has a melt disk system with 4 nozzles. Each hot runner system nozzle injects 8 products, and the molding cycle is 8s. Because the raw material of the product is plexiglass, the cost is relatively high, so using melt disk system can effectively avoid waste

Another advantage of melt disk is that it can process various materials, such as polyethylene, polypropylene, plexiglass, polycarbonate and nylon. Due to the good temperature control at the nozzle, a lower temperature can be used in the processing process. For example, in the processing of propylene in the coaxiality testing machine of polymer testing machine, when melt disk is used, the temperature can be reduced by 50 ℃ ~ 60 ℃ compared with that under normal circumstances. Generally, the processing temperature of the system using melt disk can be 10% lower than that of the system without melt disk. Using low processing temperature has two advantages: less pressure is applied to the product, thereby reducing warpage; It saves energy, cools faster and improves the forming cycle

the use of multi nozzle will make the area control simpler, which will also save costs. With traditional nozzles, 8 areas need to be controlled at each nozzle, which will directly increase the cost of the controller and the mold. With multi nozzle, only two areas need to be controlled

melt disk system is easy to install. Its gate insert must be installed on the side of the probe seal, and the positioning block must be installed vertically on the gate insert

at present, many medical products manufacturers have used melt disk system to produce pipettes, syringes, needle interfaces, etc. Many processors in other fields are also considering adopting this new hot runner technology. (end)

Copyright © 2011 JIN SHI