EWIKON L2X, Руководство по эксплуатации

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59 HPS-III-Heißkanalsystem_Inbetriebnahme-System-Einzeldüsen-L2X-NV_BA_V-2-0_EN
Instructions for the operation of valve gate systems
In general the start-up of valve gate systems is carried out analogous to other externally heated systems. (see chapter
„6.3.1 First-time start-up and filling of a HPS III hot runner system“ and „6.3.2 Start-up of an already filled HPS III hot runner
system“. However, when operating valve gate systems some additional instructions must be followed:
• In order to check the valve pin length mould and hot runner must have reached their operating temperature.
• Valve pin movements must be carried out at operating temperature only.
Instructions for disassembly
• When dismantling the mould from the machine or when disassembling the hot runner system the valve pins should
always be moved into their back position (gate open) in order to prevent them from being damaged.
• Before disassembling the hot runner system all hot runner components must have reached ambient temperature.
For this the mould cooling should stay switched on for a sufficient time after the heaters for nozzles and manifold have
been switched off.
Pneumatic drive:
•
Pneumatic pressure: see chapter „3.3 Hydraulic / pneumatic specifications (drive units)“.
• It is recommended to lubricate the compressed air with fully synthetic oil. The amount (drops/hour) depends on the
number of cavities and the nozzle size.
•
Example: valve gate system with 6 mm flow channel, 24-drop: 2 drops/hour (worth 12 drops/1000 liters of compressed air)
Hydraulic drive:
• To prevent thermal decomposition of the hydraulic oil the drive unit is equipped with a direct (screwed-on drive unit) or
indirect (e.g. cooling channels in the clamping plate) water cooling. It must be ensured that the backflow temperature of
the water does not exceed 85 °C.
• The system must only be heated when the mould cooling is switched on.
•
Hydraulic pressure: see chapter „3.3 Hydraulic / pneumatic specifications (drive units)“.
Electric drive:
• The maximum permissible environmental temperature for the drive units is 70 °C (158 °F).
• Actuation of the drive units only when the hot runner system has reached set temperature.
Please make sure that the supply channels have a sufficient size. If possible, the diameter should be between 8 mm
and 10 mm. Especially when using the valve gate as system nozzle a balanced supply channel layout should be provided.
6.4 Instructions for the operation of valve gate systems
NOTE!
When using gate exchange inserts it must be ensured that the valve pin is only operated when the hot runner system is filled
with melt.
When operating the valve pin in an unfilled system the gate exchange inserts can be pulled out of their fit and tilted when mo
-
ving the valve pin backwards. This causes damage in the gating geometry.
When valve pins are operated in an unfilled system a clamping device must be provided in order to prevent the gate exchange
inserts from being pulled out. Suitable solutions are the use of flat headed cylinder screws, clamping sleeves or retaining rings.
Depending on the available installation space EWIKON can recommend a suitable clamping version.
Use of gate exchange inserts