Nozzle needle sealing

Support elements and device drives in customary standard machine versions may be employed for the installation of a silicone cylinder module. A drive for a hydraulic needle sealing nozzle must also be provided. With the use of cold runner nozzles with needle sealing or with a cold runner head, the needle sealing nozzle on the machine can be omitted. Figure 7.9 depicts a LSR cylinder equipment kit. 

Cold runner systems that are ready to use are offered as standard in the marketplace. These fimction especially well with needle sealing nozzles that are controlled hydraulically or pneumatically. In order to allow integration with the process sequence of the injection moulding machine, interfaces were developed for control of this type of cold runner. The machine control unit also monitors the position of the needles. 

The simple cold runner nozzle with hydraulic needle sealing system, as shown in Figure 7.11 makes possible either direct or indirect injection of silicone parts. Advantages in the application of this system are good thermal separation between the cold nozzle and the heated mould and the flat gate location on the moulded part. 

Control of the needle sealing nozzle through the machine eontrols. 

Cold runner systems are the state-of-the-art in mould technology. Here, mould-integrated or maehine-integrated cold runner systems with needle sealing nozzles are generally used. 

Fuel-handling systems (diaphragms for fuel pumps, see Figure 5.5, fuel hose or fuel hose liner, inject or nozzle seals, needle valves, filter casing gaskets, fuel shutoff valves, carburetor parts)... 

Finally the hydraulic GIT needle shut-off nozzle is opened and the material cushion is injected for sealing as shown in Figure 10.18c. 

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