Design Guidelines
Design Guidelines
Cavity Design
To maximize the integrity and life of the gate area, various factors must be considered:
Recessed Gate Areas
When designing gates into recessed areas such as
dimples, a generous radius should be incorporated to
avoid extended thin sections of plate steel (see figure at
right).
Nozzle Seal Off Diameter
Nozzle Seal Off Diameter
To provide a durable nozzle seal diameter surface in the
gate bubble, a surface hardness range between 49 - 53
Rc is recommended (see figure at right). If softer
materials are used (e.g. BeCu), these should be hard
chrome plated to increase hardness.
Thin Section
Gate Steel
Hardened tool steels such as 49 - 51 Rc AISI H13/DIN 1.2344 provide a good combination of strength and ductility.
EDM Process
It is not recommended to EDM (electro-discharge machine) the gate area. A hardened surface layer resulting from the
EDM procedure makes the steel increasingly brittle, potentially leading to premature gate failure. It is also good practice to
machine the gate hole after hardening to avoid brittleness, caused by rapid quenching.
Gate Cooling
Gate area cooling is required to remove excess heat generated
by the system. Sufficient cooling provides many benefits
including:
•
Consistent gate quality
•
Consistent gate vestige
•
Greater control over material stringing
•
Greater control over resin drool
•
Greater control of gate blushing
•
Faster cycles
Gate Cooling
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Optimized Gate Cooling (Key Elements)
1) Minimize the distance from the cooling channel to the gate
detail The maximum recommended distance between the
cooling channel and the gate detail is 3 times the cooling
channel diameter.
2) Cooling should surround the insert. The cooling water should
reach flow speeds that cause effective mixing of the fluid. For
most inserts, a flow rate of about 6.8 - 8.3 liters (1.8 - 2.2 gallons)
per minute is sufficient.
3) The gate insert material affects heat dissipation and longevity.
Insert materials such as H13 (material of choice) and 420 SS are
7x less heat conductive than BeCu Alloys. The trade-off with
conductivity is hardness and gate life. Material choice will
depend upon the number of projected cycles and the cycle time
goals,
Extended Tips
Should not have cooling in front of seal ring
* Minimum of 1-1.5X cooling diameter clearance to nozzle bore
** Position the cooling centerline at the mid-point of the seal ring
locating diameter
*
Seal Ring
**
Independent Circuits
The cavity plate cooling circuit should be independent of the
manifold plate cooling circuit. This prevents coolant from leaking
onto the hot runner components whenever the plates are
separated.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Gate Inserts
Gate Insert
Gate inserts provide an effective method of cooling the
gate area, since the entire circumference is cooled.
Cooling circuits for the gate insert should be
independent from the plate cooling circuit to provide
better control. The gate insert is a replaceable wear
item.
Gate Cooling
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Cavity Plate Interface Bolts
Cavity plate interface bolts are used to fasten the cavity plate to
the hot runner.
Hot Half
The interface bolts should be installed from the clamp (moving)
side of the cavity plate, to enable separation of the cavity plate
while the mold is still secured within the machine press.
Cavity Plate
Latching
Nozzle tips, nozzle thermocouples, nozzle heaters, and nozzles
are replaceable while the hot runner remains in the press,
minimizing downtime when performing maintenance.
Interface Bolts
Cavity Plate
Latch
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Machine Interface
Machine Nozzle Requirements
To prevent pressure loss, dead spots, and to provide a leak-free
seal, the mating surfaces and orifice diameters of the machine
nozzle and sprue bushing must match.
To optimize hot runner performance, the sprue bushing orifice
should be the same diameter as the primary sprue bushing flow
channel.
Restricted
Size
Optimal Size
(preferred)
Sprue
Bushing
Shut Off Nozzle
Resin decompression within the hot runner melt channels is required for each molding cycle. Resin decompression is
essential for controlling gate vestige and minimizing material stringing.
Husky recommends that a shut-off nozzle be incorporated onto the machine injection unit. The shut off nozzle:
•
Allows screw recovery after decompression without re-pressurizing the melt within the hot runner system.
•
Enables screw recovery during mold open, which may lead to reduced cycle times.
Melt Filters
Melt filters are used to screen out any contaminants that may be present within the melt. However, melt filters increase
pressure loss, and can prevent material decompression. Melt filters are not recommended when molding small parts, since
decompression is essential for producing consistent small gate vestige.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Hot Runner Plate Design Guidelines
Stainless steel is the preferred material for plate manufacture. Suitable steel types are listed below:
Type
AISI 4140
AISI P20
AISI 420
DIN 1.2316
Hardness (Rc)
30 - 35 Rc
30 - 35 Rc
30 - 35 Rc
30 - 35 Rc
Manifold Pocket / Pillar Support
Husky recommends that a pocket be machined into
the manifold plate for the manifold. The manifold
pocket:
•
•
Allows close positioning of the plate bolts to the
nozzle components, minimizing plate deflection.
Provides superior structural support for the mold
and cavities.
Manifold
Manifold
Pocket
An air gap should be maintained between the manifold
and manifold pocket to thermally insulate the manifold
from the surrounding plates.
Plate Bolt
(see chart
following page)
The structural rigidity of the design is increased with
the incorporation of pillar supports. Pillar supports:
•
Resist manifold plate deflection, by absorbing
machine clamping pressure.
•
Pillars allow additional fastening of the manifold
plate to the backing plate within the manifold
pocket.
Manifold
Plate
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Plate Bolting
To maintain constant seal-off and minimize plate deflection, bolts should be positioned around each nozzle drop and along
the outside plate perimeter.
Bolt Size
M8 (5/16 UNC)
M10 (3/8 UNC)
M12 (1/2 UNC)
M16 (5/8 UNC)
M20 (3/4 UNC)
Ultra 250
1.0 (All Pitch)
0.75 (Small Pitch)
1.0 (Large Pitch)
0.5 (Small Pitch)
0.75 (Large Pitch)
N/A
N/A
Recommended Quantity Per Drop
Ultra 500
Ultra 750
Ultra 1000
1.0 (All Pitch)
N/A
N/A
0.75 (Small Pitch)
N/A
N/A
1.0 (Large Pitch)
0.5 (Small Pitch)
3 (All Pitch)
3 (All Pitch)
0.75 (Large Pitch)
N/A
3 (All Pitch)
3 (All Pitch)
N/A
3 (All Pitch)
3 (All Pitch)
Ultra 1250
N/A
N/A
3 (All Pitch)
3 (All Pitch)
3 (All Pitch)
The quantity and size of bolts assigned to each drop location is dependent upon the nozzle series and the number of drops
(see table above). For systems greater than 12 drops, it is acceptable for drop locations to share drop bolts.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Plate Cooling
Plate cooling circuits maintain a uniform mold plate temperature and match thermal expansion of the mold plates.
To design a uniformly cooled mold, consideration must be given to the cooling circuit layout, number of channels, lengths,
and diameters. Typical cooling circuit layouts for 2, 4, 6, and 8 drop systems are provided below.
2 Drop
4 Drop
The cooling circuit should be routed around areas
of high heat transfer, while maintaining a minimum
material thickness of 5,0 mm (0.20") between the
cooling line and other features.
Thermal Gate
6 Drop
8 Drop
5,0
(0.20")
5,0
(0.20")
3,0
(0.12")
Valve Gate
Backing Plate Cooling
Manifold Plate Cooling
5,0
(0.20")
5,0
(0.20")
5,0
(0.20")
NOTE: Avoid routing water lines in a manner that would result in uneven cooling of the nozzles and cavities.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Wire Grooves
Wire Grooves
Power and thermocouple wires are typically routed to the
electrical connectors within wire grooves. Wire grooves:
•
Protect the machine operator from live wires.
•
Provide orderly routing of hot runner wires.
•
Prevent potential wire damage.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
TOP
OPERATOR
AIR
A hot runner requires a number of service connections
such as electrical for heaters, water for plate cooling
and air for valve gate operation. Locations for these
connections are flexible, however based on experience
the schematic indicates recommended positions.
ELECTRICAL
Service Connections
AIR
Cavity Numbering
Clear nozzle identification is necessary to ensure the
hot runner properly interfaces with the mold, and that
the nozzles are mapped correctly. The sequence
illustrated to the right is recommended for simplicity.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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WATER
AIR
WATER
Design Guidelines
Valve Gating Design Considerations
To ensure optimum gate quality, valve stems must respond quickly to the open/close signals. To avoid sluggish valve stem
movement, the following should be considered prior to installation:
•
Air supply should be clean and dry at a pressure
between 550-830 kPa (80-120 psi). For thin wall
parts and engineering resins the pressure should
be between 100-120 psi.
•
A four way solenoid valve is required to activate
valve stems.
•
Quick exhaust valves should be installed on both
air lines to increase the speed at which the stems
open and close.
Gate Close
Gate
Close
Gate
Open
Line A
Line B
•
Quick air disconnects are not recommended
since these can cause flow restrictions.
•
Air plumbed direct from compressor.
•
Minimize length of air lines.
•
Use a Husky Air Kit for optimal performance.
Exhaust B
Exhaust A
Quick
Exhaust
Valve
Solenoid
(Machine indicates
when to actuate)
Solenoid
Gate Open
Gate
Close
Line A
Gate
Open
Line B
Exhaust B
Exhaust A
Quick
Exhaust
Valve
Solenoid
Solenoid
(Machine indicates
when to actuate)
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Controller Interface
Voltage Supply
To determine the correct manifold heater wattage, the available voltage supply must be specified. This practice is
necessary since a significant wattage reduction can occur if the lower voltage is not compensated for. For a given heater
the power output at 208V is only 75% of that at 240V.
Voltage Supply
240 V
208 V
Wattage
2,880 W
2,160 W
Amperage Limitations
The amperage limit for each zone of the temperature controller needs to be identified. This ensures that the manifold
heaters will not exceed the amperage limit.
Electrical Connectors
Electrical connectors are supplied with complete hot runner
systems (optional for manifold systems). Refer to Electrical
Connectors in the Accessories Section for installation
information.
Connectors are available with either side or end clamps, and top
or side entry, depending upon customer preference.
Side Clamp
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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End Clamp
Design Guidelines
Husky Standard Electrical Connector Requirements
Establishing an electrical wiring and connector standard will allow future interchangeability of hot runners and temperature
controllers. The following Husky standards have been developed around typical controller capabilities for systems ranging
from 2 to 16 drops.
The departure from the standards may be required if space is not available or if the current requirements exceed the
connectors limitations.
2-8 Drops
For applications up to 8 drops, two 24 pin connectors are sufficient: one for power, and the other for thermocouples.
24 Pin
(Power)
24 Pin
(Thermocouple)
Standard connector pin mapping for both power and thermocouples is listed below. Pins for both connectors are rated to
16A.
Pin
Sprue Heater
Manifold Zone #1
Manifold Zone #2
Tip #1
1
2
3
4
13
14
15
16
Tip #7
Tip #8
Spare
10
11
12
22
23
24
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
2-8 Drop HR System Alternative (DME Standard)
An alternative approach, is to employ one 25 pin connector for power and one 24 pin connector for thermocouples.
25 Pin
(Power)
24 Pin
(Thermocouple)
Standard connector pin mapping for 24 pin connectors shown on previous page.
Standard connector pin mapping for 25 pin connectors.This connector is used for power. Pins are rated to 10A.
Sprue Heater
Manifold Zone #1
Manifold Zone #2
Tip #1
Pin
A1
A3
A5
A7
Tip #7
Tip #8
Spare
C5
C7
A9
12-16 Drop HR System
Applications between 12 to 16 drops use the following connector types.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Figure 1-4: 12-16 Drop System Connector Configuration
6 Pin
(Power)
16 Pin
(Thermocouple)
32 Pin
(Power)
32 Pin
(Thermocouple)
Standard connector pin mapping for 6 pin connectors. Pins for zone control are rated to 30A.
Pin
Sprue Heater
1
2
Manifold Zone #1
3
4
Manifold Zone #2
5
6
Standard connector pin mapping for 16 pin connectors. This connector is used for controlling manifold thermocouples.
Pins are rated to 16A.
Pin
Sprue Heater
1
9
Manifold Zone #1
2
10
Manifold Zone #2
3
11
Manifold Zone #3
4
12
Manifold Zone #4
5
13
Manifold Zone #5
6
14
Spare
7
15
Spare
8
16
Standard connector pin mapping for 32 pin connectors. This connector is used for nozzle power and thermocouples. Each
connector can accommodate 16 nozzle zones. Pins are rated to 16A.
Pin
Tip #1
1
9
Tip #2
2
10
Tip #7
Tip #8
Tip #9
Tip #10
7
8
17
18
15
16
25
26
Tip #15
Tip #16
23
24
31
32
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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2009.10.13
Design Guidelines
Stack Hot Runner
Husky offers 2 level stack hot runners with Ultra 250, 350, 500,
750 and 1000 nozzles . A 2 level stack mold will nearly double
the output per machine of a single face mold.Husky’s experience
gained in building over 2500 stack hot runners assures that all
aspects of integrating the hot runner into the mold will be taken
into account during design.
In addition to 2 level stack systems there are also 3 level and 4
level systems available.
Moving Side
Cavity Plate
Stationary Side
Cavity Plate
Machine Tie Bars
Hot Runner
Sprue
Bar Length
Mold
Shut Height
Mold Opening
Stroke
Example of standard 2 level stack system
Standard Sprue Bar
Standard sprue bars are solid sprue extensions that connect the hot runner with the
machine nozzle.
Split Sprue Bar
Split sprue bars allow free access to the molding surface without obstruction.
Back-to-Back Valve Gate
Back-to-Back valve gates are available with standard and split sprue bars.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Machine Requirements For Stack Mold Operation
In order to successfully run a stack mold; a molding machine must meet several criteria:
Injection Unit
The injection unit must be able to provide double the shot weight, plasticizing ability, and injection rate than would be
required for a comparable single face mold.
Sprue Break Capability (Standard Sprue Bar Only)
The machine must feature sprue break capability. The injection unit of the machine must retract from the sprue bar to
provide clearance to prevent collision and possible damage between the injection nozzle and sprue bar when the mold
closes.
Shut-off Nozzle (Standard Sprue Bar only)
Upon sprue bar disengagement from the machine injection nozzle, a shut-off nozzle on the injection unit is necessary to
prevent resin drooling.
Shut Height Requirements
Stack mold applications require approximately double the mold shut height and clamp stroke requirements relative to single
face applications.
Center Section Support
The machine tie bars must provide accurate alignment of the hot runner during mold open and close. The machine
specifications must be reviewed to ensure that the tie bars provide sufficient support and accurate repetitive alignment.
Clamp (Standard Sprue Bar only)
The clamp will require approximately 10t greater tonnage. This increased tonnage is necessary to oppose the force exerted
by the machine nozzle on the movable platen which is usually opposed by the stationary platen.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Thermal Gate Consideration
Ultra 250, Ultra 500, Ultra 750 and Ultra 1000
For all thermal gating methods, the nozzles can be positioned back to back.
Clamp Side
Injection
Leak Proof UltraSeal
Technology
Back-toBack
Nozzles
Sprue Bar
Anti-Drool
Bushing
Minimum Hot Tip Stack Hot Runner Shutheight
Series
Ultra 250
Ultra 350
Ultra 500
Ultra 750
Ultra 1000
2x2 to 2x4
148mm
5.83 in
125mm
4.92 in
130mm
5.12 in
131mm
5.16 in
132mm
5.20 in
2x6 to 2x24
128mm
5.04 in
136mm
5.35 in
130mm
5.12 in
131mm
5.16 in
147mm
5.79 in
2x32 to 2x48
208mm 8.19 in
208mm 8.19 in
210mm 8.27 in
211mm 8.31 in
NOTE:These values are based on one L-dimension and standard housing length, different L-dimensions, custom housing
lengths and layout configurations can change these values
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Valve Gate Consideration
Ultra 350, Ultra 500, Ultra 750 and Ultra 1000
In order to accommodate customer requirements Ultra VG nozzles can be positioned offset or back to back. These designs
provide ease of assembly and service access to the cylinders provided via air plates.
Offset Valve Gate
Back-to-back valve gate (B2B)
Minimum B2B Valve Gate Stack Hot Runner Shutheight
Minimum Offset Valve Gate Stack Hot Runner Shutheight
Series
Ultra 350
Ultra 500
Ultra 750
Ultra 1000
156mm
156mm
156mm
173mm
2x2
6.14 in
6.14 in
6.14 in
6.81 in
176mm
176mm
176mm
188mm
2x4 to 2x16
6.93 in
6.93 in
6.93 in
7.40 in
Series
Ultra 350
Ultra 500
Ultra 750
2x2 to 2x8
250mm
9.85 in
252mm
9.92 in
266mm
10.50 in
2x12 to 2x32
290mm
11.42 in
292mm
11.50 in
306mm
12.05 in
NOTE:These values are based on one L-dimension and standard housing length, different L-dimensions, custom housing
lengths and layout configurations can change these values
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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2009.10.13
Design Guidelines
Standard Sprue Bar
The purpose of the sprue bar is to transfer the molten resin
from the machine injection unit to the center section. When
the mold is in the closed position, the machine nozzle seats
against the sprue bar. When the mold opens the sprue bar
moves with the center section and disengages from the
machine nozzle.
Sprue Bar
Guide
•
Husky calculates the correct sprue bar length based on the mold shut height and the required mold opening
stroke. This ensures that the end of the sprue bar remains guided in the stationary platen when the mold is in
the open position and that it will not contact the machine nozzle prematurely on mold close.
•
The sprue bar is aligned to the machine nozzle by the sprue bar guide, which is installed behind the locating
ring, or on the cavity plate. To prevent damage during operation, the sprue bar must not pull out of the sprue
bar guide during the mold opening stroke.
Anti-Drool Bushing
The function of the anti-drool bushing is to minimize
the amount of resin that drools out of the sprue bar
when it is not in contact with the machine nozzle. As
the sprue bar moves with the center section during
mold open, the residual melt pressure in the manifold
forces the anti-drool bushing backward
Residual Pressure
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Offset Sprue Bar
When the sprue bar can not be positioned at the mold centerline, an offset sprue bar can be used. Using an offset sprue
bar requires additional mold shut height to accommodate the transfer manifold attached to the stationary platen. The sprue
bar can be positioned at any side of the mold.
Transfer
Manifold
Heat Shield
Offset Sprue Bar
Sprue Nozzle
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Standard Sprue Bar Installations
Standard Small Sprue Bar
Small Sprue bar compatible with the following systems:
- Ultra 250 HT stack
- Ultra 350 HT stack, Offset VG stack, B2B VG stack
- Ultra 500 HT stack, Offset VG stack, B2B VG stack
- Ultra 750 HT stack, Offset VG stack, B2B VG stack
- Ultra 1000 HT stack, Offset VG stack, B2B VG stack
Heat Shield Installation Plate A
35.0 [1.38]
2x R 0.8 [.03]
4x FULL R
2x 25.4 [1.00]
38.0 [1.50]
38.0 [1.50]
2x 14.0 [.55]
47.6 [1.87]
73.0 [2.87]
Heat Shield Installation Plate A
2x R 0.8 [.03]
2x 20.0 [.79]
73.0 [2.87]
110.0 [4.33]
38.0 [1.50]
90.0 [3.54]
2x 14.0 [.55]
35.0 [1.38]
Locating Installation Ring
Sprue Bar Thru Hole Installation
in Core Plates
140.0
2x R 17.5 [.69]
+0.02
0
5.51
+.008
- .000
2.750
+ .001
- .000
R 0.8 [.03]
69.85
+ 0.03
0
R 0.8 [.03]
38.0 [1.50]
6.0 [.24]
35 0 [1 38]
x 19.0 [.75]
19.0
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
2009.10.13
220
0
- 0.03
+ .000
.75 - .001
Design Guidelines
Standard Medium Sprue Bar
Medium Sprue bar compatible with the following systems:
- Ultra 250 HT stack
- Ultra 350 HT stack, Offset VG stack, B2B VG stack
- Ultra 500 HT stack, Offset VG stack, B2B VG stack
- Ultra 750 HT stack, Offset VG stack, B2B VG stack
- Ultra 1000 HT stack, Offset VG stack, B2B VG stack
Heat Shield Installation Plate A
50.0 [1.97]
2x R 0.8 [.03]
2x 25.4 [1.00]
2x R 14.0 [.55]
50.0 [1.97]
100.0 [3.94]
4x FULL R
62.8 [2.47]
88.2 [3.47]
Heat Shield Installation Plate A
2x R 0.8 [.03]
2x 20.0 [.79]
140.0 [5.51]
100.0 [3.94]
50.0 [1.97]
120.0 [4.72]
2x 14.0 [.55]
50.0 [1.97]
Sprue Bar Thru Hole Installation
in Core Plates
Locating Installation Ring
140.0
2x R 25.0 [.98]
R 0.8 [.03]
+ 0.20
0
+ 0.03
100.0
0
5.51
+ .008
- .000
2x MB
+ .001
3.94 - .000
50.0 [1.97]
R 0.8 [.03]
6.0 [.24]
0
- 0.03
.75
+ .000
- .001
2x 25.0 [.98]
19.0
50.0 [1.97]
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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2009.10.13
Design Guidelines
Standard Large Sprue Bar
Large Sprue bar compatible with the following systems:
- Ultra 250 HT stack
- Ultra 350 HT stack, Offset VG stack, B2B VG stack
- Ultra 500 HT stack, Offset VG stack, B2B VG stack
- Ultra 750 HT stack, Offset VG stack, B2B VG stack
- Ultra 1000 HT stack, Offset VG stack, B2B VG stack
Heat Shield Installation Plate A
60.0 [2.36]
2x R 0.8 [.03]
4x FULL R
2x 25.4 [1.00]
45.0 [1.77]
105.0 [4.13]
2x 14.0 [.55]
70.6 [2.78]
96.0 [3.78]
Heat Shield Installation Plate A
2x R 0.8 [.03]
2x 20.0 [.79]
138.0 [5.43]
45.0 [1.77]
105.0 [4.13]
118.0 [4.65]
2x 14.0 [.55]
60.0 [2.36]
Sprue Bar Thru Hole Installation
in Core Plates
Locating Installation Ring
2x R 30.0 [1.18]
140.0
+ .008
+ 0.20
5.51
- .000
0
108.0
+.001
+ 0.03
4.25
- .000
- 0
R 0.8 [.03]
45.0 [1.77]
R 0.8 [.03]
6.0 [.24]
2x 22.5 [.89]
24.0
60.0 [2.36]
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
2009.10.13
2x M8
222
0
+ .000
.94
-0.03
- .001
Design Guidelines
Split Sprue Bar
The Split Sprue Bar (SSB) transfers resin from the machine injection nozzle to the hot runner of a stack mold. The
transfer is designed to free the parting line from component interference while preventing resin leakage.
The SSB accomplishes this through the connection of two independently controlled assemblies enclosed within the mold.
These assemblies interface with each other at the parting line during mold closed and disengage upon mold open.
This makes free drop of parts possible and allows unrestricted robot access for part take-off.
There are two SSB configurations: Inline and Offset. Located in the center of the mold, the Inline version is mounted
co-axially with the machine nozzle. Resin flows though the inline valve gate unit mounted in the core backing plate
and transfers melt to the moving side split sprue bar assembly through the tip interface at the parting line.
The Offset SSB employs a transfer manifold system mounted to the stationary platen to route flow from the injection nozzle
to a SSB unit located at a place of convenience to the mold design.
Key Features:
Taper stem shut-off
•
Radial taper at nozzle lead-in for alinement
Patented sliding joint
•
Sliding joint with spring packs for robustness
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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2009.10.13
Design Guidelines
Two standard throughput options are available, “Medium” and “Large”. Husky’s Application
Engineering personnel can assist in the selection of the proper throughput option for your system. The Large SSB is
available in an Offset configuration only.
Inline
Offset
The SSB is located on the center line of the
mold and is directly fed by the machine nozzle
An Offset system allows the SSB unit to be
positioned freely in the mold frame. A transfer
manifold routes the feed from the machine
nozzle to the SSB unit location.
204mm [8.0”]
Ø 73mm [2.87”]
Ø 138mm [5.44”]
Hole through mold plates
Hole through platen
Ø 127.4mm [5.0”]
Minimum Shutheight:
- Medium SSB: 200mm [7.87"]
- Large SSB: 216mm [8.50"]
Example: Medium size Split Sprue Bar
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
UltraSync
• Synchronized stem actuation
- Better shot to shot consistency
- Precise repeatability
• Tight pitch spacing
- Minimum 18mm drop to drop pitch
spacing
when used with the Ultra 350
• Clean room compatibility
- Electric
• Consistent LX stem force
• Stem easily accessibility in the machine
• Multiple nozzle sizes
- Ultra 350, Ultra 500, Ultra 750
- Available for VG or VX tip configuration
• Two actuation options
- Servo motor (electric)
- Hydraulic
Please contact Husky for further information
22.3
[0.878]
25.4
[1.00]
18.0
[0.709]
44.5
[1.75]
44.5
[1.75]
25.4
[1.00]
18.0
[0.709]
22.3
[0.878]
R 40.4
[1.60]
R 32
[1.26]
R 31.5
[1.242]
Ultra 350 Pitch Spacing
Ultra 500 Pitch Spacing
Ultra 750 Pitch Spacing
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
225
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Design Guidelines
Center Section Support Types
The center section of a stack mold is supported by the tie bars of the injection molding machine using one of three
methods.
•
Horizontal Support
•
Vertical Support
•
Machine Mounted Carrier
For all three methods, it is essential that the machine be level to avoid unnecessary wear on the mold and machine
components caused by misalignment.
Horizontal Support
The horizontal support approach uses an H-shaped sled that rides on the lower machine tie bars to support the hot runner.
The upper machine tie bars are used to guide the sled during normal operation. The wide stance of the horizontal support
enables the weight of the hot runner to be evenly distributed along a wide section of the machine tie bars. A horizontal
support is used when the mold is wider than the machine tie bar spacing. For safety reasons the mold must be at least as
wide as the center to center tie bar spacing. The mold must also have a minimum of 70,0mm (2.76") and a maximum of
120,0mm (4.72") clearance over the lower tie bars and a minimum of 30,0mm (1.18") clearance beneath the upper tie bars.
Two options exist for controlling hot runner movement:
•
Rack and Pinion Gear Mechanism
•
Harmonic Linkage Mechanism (available only with Husky machines)
>210,0 (8.27")
>30,0 (1.18")
Clearance
>70,0 (2.76")
Clearance
<120,0 (4.72")
Clearance
Mold Edges Must Be
Wider Than Tie Bars
Inside Spacing
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Vertical Support
The vertical support uses an hourglass shaped outrider that is fastened to the operator and non-operator sides of the
center section. The weight of the hot runner is evenly distributed over a wide area of the lower machine tie bars by half
shoes. The mold must be between 10,0mm (0.39") and 85,0mm (3.35") narrower than the horizontal tie bar spacing. The
upper tie bars provide guidance and stability to the center section during operation. A rack and pinion gear mechanism
provides center section movement.
Drop Limiters
Mold Support
Tie Bar Spacing
>420,0 (16.54")
<920,0 (36.22")
Mold to Tie Bar Spacing
<10,0 (0.39")
>85,0 (3.35")
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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Design Guidelines
Controlled Center Section Movement
Controlled movement of the center section is critical to ensure that as the mold opens, the hot runner always remains
centered between the clamp and injection sides of the mold. The recommended methods of controlling center section
movement include:
•
Rack and Pinion Mechanism (Single and Multiple Gear)
•
Harmonic Linkage Mechanism (available only with Husky machines)
The method employed for a given application is customer specified. Each method is examined in greater detail in the
sections that follow.
Rack and Pinion Mechanism
With the rack and pinion single gear mechanism, two racks are employed per mold side. The top rack is fastened
to the clamp side while the bottom rack is fastened to the injection side.
Design Considerations:
•
Machine stroke must be 25,0 mm (0.98") less than the mold shut height to ensure that rack engagement is
maintained.
Rack Mounting to Mold
230,0mm (9.06")
Keep the Surface of this
Area Clear of all Mold
Components to Avoid
Interference with Racks
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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228
Design Guidelines
Harmonic Linkage
The Harmonic Linkage mechanism is only available for use in a Husky machine. With the harmonic linkage mechanism, a
propeller and harmonic arm mechanism is fastened to the center section. The harmonic linkage mechanism is used for
molds that have a short ejection stroke and a machine stroke less than 305mm (12.01").
Keep Sides of Mold Clear of all
Components to Avoid Interference with
Harmonic Linkage Movement
Harmonic Arms
Propeller
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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TOP
Plate
Width
Customer
Specified
Water Fittings
Type & Location
Horizontal
Tiebar Spacing
Customer Specified Electrical
Connector Type
230
Customer Features
X & Y Location
Customer Mold
Drop Number
X & Y Location
OPERATOR
SIDE
Customer Mold Interface
Tap X & Y Location
Clamp Slot X & Y Location
(Width, Length, Depth)
Latch Tap
Guide Pin X & Y Location
Type & Diameter
Machine Type
Tiebar Diameter
Maximum
Hot Runner
Thickness
Guide Pin Protrusion
Measured from
Clamp Face of
Manifold Plate
Customer Mold
Interface Taps
(Specify Thread,
Depth, Quantity)
Customer Specified LDimension
Distance from Clamp
Face of Manifold Plate
to Mold Surface
Latch Tap
Customer Features
Critical Dimensions Needed:
ie. Depth, Width, Length,
Diameter
Design Guidelines
Customer Drawing Requirements (Hot Runner Systems)
Before Husky can begin engineering, the hot runner interfacing features indicated in the figure below must be defined by
the customer when submitting the Mold Layout drawings along with the Design Information Form.
Contact Husky if you have any questions when completing the Mold Layout Sheets or the Design Information Form.
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
Plate
Length
Vertical Tie Bar
Spacing
Design Guidelines
Customer Drawing Requirements (Manifold Systems)
Before Husky can begin engineering, the customer features indicated in the figure below must be defined by the customer
when submitting the Mold Layout drawings along with the Design Information Form.
Plate
Width
Customer Specified Electrical
Connector Type
TOP
Customer Mold
Drop Number
X & Y Location
OPERATOR
SIDE
Customer Specified
L-Dimension
Distance from Clamp
Face of Manifold
Plate to Mold
Surface
Contact Husky if you have any questions when completing the Mold Layout Sheets or the Design Information Form.
Plate
Length
Please confirm all dimensions and nozzle/gating suitability with Husky prior to machining.
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