Hot runner nozzle - Günther Heisskanaltechnik ...

Notes on valve needles
The needle length is dependent on the nozzle length,
type of actuation and manifold structure. The needles
have a basic hardness of 64 HRC (HSS steel) and are
coated. The needles are fitted with a cylindrical seal
towards the cavity and are adjustable.
The 2 mm Ø needle design for nozzles with material
tube-Ø 4-6 mm, threads M6x 0,5
gate-Ø: 0,8 mm, 1,0 m, 1,2 mm, 1,4 mm, (1,6 mm).
The 3 mm Ø needle design for nozzles with material
tube- Ø 8 mm, threads M8 x 0,5
gate Ø: 2,0 mm, 2,5 mm.
The 5 mm Ø needle design for nozzles with material
tube- Ø 10-12 mm, threads M10 x 0,75
gate- Ø: 3,0 mm, 4,0 mm.
Tools to disassembling the needle guide (piece of PM),
see chapter 7.
Needle Ø Thread Tightening torque
M A [Nm]
Ø 2 mm M6 x 0,50 15
Ø 3 mm M8 x 0,50 30
Ø 5 mm M10 x 0,75 45
Type NEP
Type NHP
1.4. 43
iT
Thread tightening torque for needle adjustment
Maintenance
Fig.
Sliding cam mechanism
with externally accessible
grease fittings
Valve gate technology
Sliding cam mechanismus -ANES-
When fitting the sliding cam mechanism, use a hightemperature
long-life grease to lubricate the movable
parts. This allows the sliding cam mechanism to work
without any problems even at higher temperatures over a
long period of time. Make sure the mould temperature
does not exceed 100° C in the area of the frame plate/
clamping plate.
During maintenance the sliding cam mechanism must be
checked for dirt and wear. Melts that have exuded from
the manifold sealing because of the stroke movement of
the needles must be removed. In older hot-runner
systems the sliding cam mechanism can be relubricated
through the ball impact holes (DIN 3410 Form F); in new
systems the sliding cam mechanism can be relubricated
without disassembly.
Fig.
Ball impact holes
To ensure optimal greasing performance also at higher
temperatures, avoid using different greases. We
recommend the lubricating grease from Klueber
Barrierta L55/2 high temperature long-life grease. The
lubricating grease can be purchased either directly from
the manufacturer or from us. Safety data sheets can be
called up at www.klueber.com.
Introduction: Lubrication after 150.000 shots or
1x weekly.
Maintainance work (cleaning) must be done on the
needle-driving mechanisms every 400.000 shots!
This frequency depends greatly on the material to be
processed or the application. If a thermoplastic
elastomer (TPE) is being processed, it may be necessary
to do maintenance work on the sliding cam after just
approximately 200.000 shots. This also concerns
polymers, in which the viscosity is greatly reduced by the
shearing.
www.guenther-hotrunner.com
Subject to technical changes 4/11