This document discusses three plate molds and hot runner systems. It explains that three plate molds have two openings between three plates and a top gate. It also describes the components of a three plate mold like sucker pins and stripper plates. The document then discusses hot runner systems, noting that they are like extended nozzles that deliver molten plastic evenly to each cavity. It provides procedures for starting up and checking hot runner systems, preventing leaks, and checking for issues during production.

1. Understanding
Three Plate Molds
and Hot runner
System


BY
NAIK DEVANG

2. MOLDS TYPES
Two plates mold
Three plates mold
Stripper plate molds
Stack mold
Cam action mold
Hot runner mold

3. THREE PLATE MOLD
Refers to mold that have top
gate
Two opening between three
plates
Difference between stripper
plate and three plate

4. THREE PLATE MOLD

5. THREE PLATE MOLD

6. MOLD COMPONENT OF THREE
PLATE
Sucker pin to degate the runner
Runner stripper plate
Stripper & bolts uses to
sequence opening of three
plates

8. WHAT IS HOT RUNNER?
Hot runner is nothing other than
“EXTENDED NOZZLE”,ITS
SOLE PURPOSE IS TO DELIVER
THE MATERIAL TO EACH
DROP EQUALLY. The most
efficient way to accomplish this is to
have a balance manifold with equal
flow length and channel sizes from
the point of injection to each cavity.

9. WHAT IS HOT RUNNER ?
In plastics you need to heat the manifold
as the plastic is a solid granule.
Here also you need a manifold to take
the molten material to the multy cavity.
In air, water & hydraulic you put
washer or Teflon to stop the leakage.
Here also you put copper washer to
prevent the leakage.
 So both are in average similar character
you needn’t fear about the hot runner
system.

10. HOT RUNNER STARTING
PROCEDURE .
Keep controller in front of the m/c
The control system must be located to
allow free movement of air and
limited exposure to heat, dust, dirt,
moisture, and corrosive vapors.
You must be able to easily access the
front panel and the rear panel of the
temperature controller.
Check all the connections thoroughly.

11. HOT RUNNER STARTING
PROCEDURE
Connections of main plug pin :Use plug socket & pin only. Not loose
wire& runner.
Ensure neutral is connected to the machine
neutral only.( not in earthling plug)
Connections of the connecters (8 pin, 16 pin
etc ;) must be connected firmly, Should not
leave loose connected. Use connecter clamps
for firm contact.
EX:- {3 coil heaters and 2 cartridge heaters
fail due to this simple basic reasons only}.

12. CHECK POINTS
 switch on the control panel , if any abnormality is found
during the staring, switch off the controller & check
following points.
 Check all the connections once again.
 Check fuse on the controller.
 Check MCB switch on the controller
 If the above points are found OK, then check
Next following points.

13. Check T/C with multi meter. Ensure T/C is in good
condition.
 Check heaters continuity with the multi meter. If found
OK, re connect it to the connector.
Start the controller again. Module screen shows the
temperature increasing.
If any of the display shows reverse temperature that
means the T/C connection is reverse. Change the T/C
wire connection

14. Start again, now the temperature will start increasing.
First set the value to 100 c.
Once it is achieved, and then increase the value step by step
to the desired temperature.
The set value & the actual temperature should not more or
less than the tolerance allowed
If any of the display shows hi temperature then it may be the
fault of the modular, better change the modular or change
the total controller it self. Inform tool room persons.

15. Following list shows the connection of heater and
T/C diagram which are standardized in all our
moulds and controllers.
T/C
F M
M
F
HETEAR
F
M
MALE CONECTOR.
MALE CONECTOR.

16. LEAKAGE AND PREVENTIVE
MAINTENANCE
Most common location for leakage is seal off
between the nozzle and manifold.
Hot runner is accidentally overheated.
Detect a leak
Plastic can be seen coming out through
electrical connectors.
Sudden loss of random cavities or parts that
are not packed properly.

17. PREVENT LEAKS
Design
Manufacturing
Training

18. CHECK POINTS DURING
PRODUCITON
DON’T RUN PRODUCITON WITH CAVITY BLOCK
THROUGH LESS TEMP IN ONE ZONE.
CHECK AND ENSURE MATERIAL LEAKAGE
FROM MANIFOLD AT EVERY TWO HRS.
IF SHOT PIECES IS OBSERVED CHECK
FOLLOWINGS
TEMP,
LEAKAGE
NOZZLE BLOCK
RE-GRINDING MATERIAL IS NOT ALLOWED.

19. CHECK POINTS FOR MOULD
LOADING AND UNLOADING.
CONNECTOR HOOD SURFACE
WATER CONNETION
WHILE MOLD GREACING HOT
RUNNER NOZZLE TEMP.MUST CHECK.

20. THANKS