Post on 07-Aug-2018
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8/20/2019 Injection Molding Machine for PET Material
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Injection Molding Machine for PET Material
This injection molding machine is designed to produce various kinds of preforms such as water preforms, carbonated
preforms, oil bottle preforms, jar preforms and 5 gallon bucket preforms. It is ideal for PET material and all kinds of
master batches, characterized b the following features.!. This e"uipment is applied with a de#dew device to remove the dew on the mould and a chiller to cool the mould.
$. %lso, it is e"uipped with a crusher which is used for reccling defective preforms.
&. It is available with integrated dehumidifier, drer and loader or individual drer, dehumidifier, and loader.
'. %n optional robot can be used for collecting preforms.
5. This machine comes with clamping force of ()T* &)))T.
+. The weight of preforms ranges from !+g to ()g and the "uantit of cavit is of !* '(.
. The mi-er and air compressor are optional.
Technical Specifications
Device Item Unit JST-90 JST-150 JST-220 JST-280 JST-350 JST-550
PET PET PET PET PET PET
InjectionUnit
Screw
Diameter mm 42 50 65 70 75 90
Screw L/D
Ratio L/D 23 23 23 23 23 23
Theoretical
ShotVolme
cm3 200 392!5 "00 ##90 #500 24#0
Shot
$ei%ht&'S(
% 220 425 "70 #300 #639 2600
Injection're))re
*+a #43 #56 #25!2 #2"!5 #50 #37!5
InjectionRate
%/) 9" #3# 200 270 275 563
'la)tici,in%
-a+acit. %/) #5 2" 3"!2 5# 67 #32
ScrewS+ee
Ran%e
r/min 0230 0200 0##0 0##5 0#50 0#45
-lam+in%
1orce 900 #500 2200 2"00 3500 5500
-lam+in%
Unit
-learance
etween
Tie ar)
mm 360360 4#04#0 520520 5"05"0 660660 "00"0
+enin%Stroe
mm 325 400 5#0 570 660 750
*a! mm 360 430 560 6#0 720 7"0
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*ol
Thicne))
*in!*ol
Thicne))
mm #50 #50 250 250 300 350
8jector1orce
27 33 70 "7 ##0 ##0
8jector
Stroe mm #00 #20 #40 #60 #"0 #"5
'm+'ower
$ ## #5 22 22 30 45
ther)
eatin%
'ower $ 9 #2 #9!67 2#!6 24!75 30!5
il Tan-a+acit.
L 200 270 500 700 "00 #200
*achine$ei%ht
t 3!" 4!" 7!# #0!5 #5 2#
*achineDimen)ion
m 4!3#!#5#!" 4!"#!2#!" 6!##!52 7!0#!652 7!5#!752!3 9!22!#
Device Item Unit JST-120 JST-180 JST-250 JST-330 JST-400 JST-650
PET PET PET PET PET PET
Injection
Unit
ScrewDiameter
mm 45 55 65 70 90 #00
Screw L/D
Ratio L/D 23 23 23 23 23 23
TheoreticalShot
Volme
cm3 294 546 "29 ##92 24#0 372"
Shot$ei%ht
&'S(
% 330 596 900 #300 2600 4070
Injection
're))re *+a #39 #40!7 #4#!6 #47 #37!5 #49
Injection
Rate %/) ##" #92 200 232 5#2 6"3
'la)tici,in%
-a+acit. %/) 2# 32!6 3"!2 54 ##6 #27
Screw
S+ee
Ran%e
r/min 0200 0#50 0##0 0#20 0#35 0#30
-lam+in%
1orce #200 #"00 2500 3300 4000 6500
-lam+in% -learance mm 4003"0 460460 570570 620620 720720 9#0"4
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Unit
etween
Tie ar)
+enin%Stroe
mm 360 460 550 600 7#0 "60
*a!
*olThicne))
mm 400 4"0 600 6"0 720 "60
*in!
*ol
Thicne))
mm #50 200 250 2"0 250 400
8jector
1orce 27 6# 70 "7 ##0 ##0
8jector
Stroe mm #00 #30 #50 #60 200 250
'm+
'ower
$ ## #"!5 22 30 45 37:22
ther)
eatin%'ower
$ 7!43 #3!47 #"!32 23!72 30!5 42!5
il Tan
-a+acit. L 200 350 500 600 #200 #600
*achine$ei%ht
t 4!3 5!7 "!5 #2!2 #" 36
*achine
Dimen)ion m 4!55#!2#!" 5!6#!35#!"5 6!4#!5#!2 7!0#!72!# "!"2!02!25 #0!52!
PET Preform Production Line
Applications of Preform Injection Molding Machine
This preform injection molding machine is for making various kinds of water preforms, carbonated preforms, oil bottle
preforms, jar preforms and 5 gallon bucket preforms.
Features of Preform Injection Molding Machine
!. Preform injection molding machine, with clamping force from ()T to &)))T.
$. The preform weight is from !+g to ()g and the cavit "uantit is from ! to '(.
&. It is applicable to PET material and all kinds of master batches.
'. This preform injection molding machine could be e"uipped with an optional mi-er.
5. It is available with integrated dehumidifier, drer and loader or individual drer, dehumidifier, and loader.
+. It has a de#dew device for removing the dew on the mould and a chiller for cooling mould.
. %ir compressor.
(. ptional robot for collecting preforms.
/. This preform injection molding machine also has a crusher for reccling defective preforms.
Flow Chart of Preform Injection Molding Machine
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Specifications of Preform Injection Molding Machine
Deice Specification !nit "SE#$%& "SE#'%& "SE#(%&
injection
0crew dia. mm 5) +5 !))
0crew 123 ratio 123 $& $& $&
Theoretical shot 4m& &/$.5 ($/ &$(
Injection weightPET6 g '$5 /)) '))
Injection pressure 7pa !5+ !'!.+ !'/
Injection ratePET6 g2s !&! $)) +(&
Plastizing capacitps6 g2s $( &(.$ !$screw rotate speed r2min )*$)) )*!!) )*!&)
4lamping
4lamping force 89 && $5)) +5))
4learance between tie bars 7m '!):'!) 5):5) /!):(')
pening stroke mm ')) 55) (+)
7a-. mould height 7m '&) +)) (+)
7in. mould height 7m !5) $5) '))
Ejector force 89 && ) !!)
Ejector stroke 7m !$) !5) $5)
thers
7otor power 8; !5 $$ &$))) certificate, we have sold
our injection molding machines to ?%E, Iran, %ustralia, @apan, Poland, Arazil, and more countries. ;ith about !5
ears of e-perience in the manufacture of injection molding machine, we are full capable of offering ou high "ualit
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plastic processing machiner and beverage production lines, such as preform injection molding machines, PET blow
molding machines, water treatment, labeling machines, and more. Please keep browsing or contact us directl for
more informationB
The product
The PET preform, better known as preform, is accomplished through amolding process. The fused PET injected into a mold become a preform, which, by anadditional processing step (blowing), takes the form of bottles for beverages for elementary,oil or detergents use. preform is made by a !"nish! (bottleneck), which will not change in the blowing process.!#inish! diameter and thread type are the main features of the preform, features thatdetermine the kind of screw bottle cap and the use of the bottle (for still water, sparkling
water, oil, milk).$n the other hand, the tubular structure, will form the bottle in the blowing and moldingprocesses and it determines the basis weights of the "nal product% diameter, length andshape are the key elements that give the main features to the blown container.
The PET polymer, used for the production of preforms doesn&t have a colour, it&s almosttransparent, but once mi'ed with colouring additives, it can have dierent shades of colouraccording to customer reuirements.
Storage
The polymer is transported in tankers or in *ig *ags. The material, once entered into factory,is piped into + storage silos from which it&s taken depending on the productionreuirements.
Drying of PET
PET, by its nature, absorbs humidity from the atmosphere, in order to give a perfect product,it has to stand to a drying and dehumidi"cation process. The process consists in maintainingthe storage silo connected to the feeding of the PET machine for a certain period of time(which may vary depending on the nature of PET from - to + hours) during this time it&sheated with a stream of hot air at a temperature of +/0. The air heating is produced by asystem that uses the thermal oil heated by a heat e'changer connected to a group of cogeneration for the production of electric power.
Plasticization of the PET
$nce dried PET is routed through a screw in the injection chamber. 1uring this phase, thePET is heated to a temperature of about 2340 and stands to the lamination phase passingfrom the solid state (granules) to the liuid state.*efore entering into the cochlea the granule can pass through a pre5mi'er where it&s mi'edwith a colouring that, with the speci"c amount, gives the shade as reuired by the customer.
Injection molding.
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PET in liuid state is conveyed by the rotating screw in an injection chamber in such uantityas to "ll the total cavity installed on the mold. 6hen the mold is closed, the molten PET isinjected into the cavities where once in contact with the matri' will solidify and form.
The temperatures of cavities and punches are cooled by a system that allows the PET tosolidify before being ejected from the mold through a system of e'tractors.
Cooling
The solidi"cation process ends when the preforms are ejected from the mold by a cooledautomated gripper.
Packing
$nce completed the cycle of cooling, the preforms are deposited on conveyor belts and sentin suitable containers called $7T*89:.
Handling and Storage
The $7T*89: are taken by an automated system made by ;
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e.Make sure there are no severed lines to the heater.
f. Make sure the nozzle is not clogged. If the nozzle clogs frequently, raise the mold temperature or
shorten the cycle time.
g.Increase injection speed
a.Raise the mold temperature.
b.Increase the mold gas release.
c.Increase gate cross section surface area.
d.Increase the molded product thickness.
e.Add ribs to the molded product design to improve flowability.
a.Choose a low-viscosity high flow material type.
b.Apply surface lubricant. (Add 0.05-0.1% by weight.)
Flow marks
. Description
Ring shaped miniature bands appear on the molded product surface around gates or narrow
sections.
Ⅱ
. Causes
The molten polymer cools rapidly within the mold and becomes highly viscous. Once that molten
polymer starts to coagulate, it gets pushed by the molten polymer injected afterward and forms
miniature bands.
Ⅲ. Countermeasures
a.Increase the nozzle diameter. Increase the nozzle temperature
b.Increase injection speed.
c.Increase injection pressure.
d.Raise the cylinder temperature.
e.Reduce the cushion. (Reduce the charging amount.)
a.Increase the mold temperature.
b.Provide a cold slug well.
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c.Increase the gate cross section surface area.
d.Create more distance between the gates and the location of the mold coolant.
a.Apply surface lubricant.
Silver streaking
. Description
Streaks of a silvery white color appear in the material flow direction.
Ⅱ. Causes
a.Material is absorbing water.
b.Material is contaminated with another type of material.c.Aeration is occurring during molding.
d.Too much additive is present.
Ⅲ
. Countermeasures
a.Apply back pressure to generate a kneading effect.
b.Slow down injection speed.
c.Thoroughly clean molding machine cylinders.
a.Increase (or decrease) the size of the runners and gates.
b.Increase the mold temperature.
c.Change the gate locations.
a.Pre-dry thoroughly.
b.Install an ultrared light inside the hopper.
c.Investigate for potential contamination.
Poor weld line
. Description
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The material splits off and flows in two or more directions. When the divergent flow fronts converge
again, hair-like lines appear where they meet. This results in reduced strength, as well as burn-mark
and bubble defects.
Ⅱ
. Causesa.Material splits and flows in separate directions, then converges again.
b.Polymer temperature is too low. Polymer is not fully melted.
c.Difficulties in venting gas and air.
Ⅲ
. Countermeasures
a.Raise the resin temperature
b.Increase the injection pressure.
c.Increase the injection speed.
a.Provide a cold slug well where weld lines occur.
b.Provide a gas vent.
c.Change the gate locations. Or increase the number of gates.
d.Stop using mold parting agents.
e.Change the gate locations so that the weldlines occur in locations less susceptible to external
forces if weld strength is an issue.
a.Choose a low-viscosity high flow type material.
Voids
. Description
The presence of holes inside molded products
Ⅱ. Causes
a.Change in density as the material changes from a molten to a coagulated state.
b.The surface of the molded product loses heat rapidly through the mold wall and the polymer
hardens. As a result, the polymer is pulled outward, causing all shrinkage to concentrate in the
thickest parts of the product leaving holes within the product. In molded products with a
thickness greater than 6 mm, voids are very difficult to avoid.
c.Air gets trapped within the molten polymer, leaving bubbles within the product
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a.Lower the mold temperature.
b.Make the mold temperature uniform.
c.Change the gate locations.
d.Make the gates larger.
e.Make the runners shorter.
a.Choose a highly viscous grade.
Warpage
. Description
The molded product warps immediately following or at some time following molding where the mold
cavity should be straight.
Ⅱ
. Causes
Residual stress from the molding process is released, causing deformation.
Ⅲ
. Countermeasures
a.Decrease the injection pressure.
b.Lower the cylinder temperature setting.
c.Lengthen the cooling time.
Mold
a.Make the thickness of the molded product uniform.
b.Eliminate undercuts.
c.Operate the knock out pins in a uniform fashion.
d.Provide multiple knock out pins.
e.Change the gate locations.
f. Lower the mold temperature.
Screw engagement failures
. Description
When feeding material for measurement, the screw rotates but does not engage the screw thread, or
the screw does not turn at all.
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Ⅱ
. Causes
Occurs when the coefficient of friction between the material and another material, the material and
the screw, or the material and the heating cylinder is unusually low or unusually high.
Ⅲ
. Countermeasures
a.Install a screw equipped with a back-flow check valve.
b.Choose a short compression type screw.
c.Change the cylinder temperature setting. Lower if the screw turns without engaging, raise if the
screw is not turning.
d.Check to make sure no lines to the cylinder heater have been severed.
e.Perform an empty shot at least five times.
a.Apply a surface lubricant.
b.Make the granularity of the material uniform.
Sticking of parts in the mold
. Description
Ordinarily a molded product is removed from the mold by having the product stick to the moving side
of the mold when the mold opens, after which the product is ejected using ejector pins. Sticking
occurs when the part fails to separate from the stationary mold or from the moving mold. In the case
of the latter, the problem could result in broken ejector pins.
Ⅱ
. Causes
Possible causes include: the mold draft is too small; there is too much residual pressure from the
molding process; too much shrinkage occurred; or the mold finish is perpendicular to the part release
direction.
Ⅲ
. Countermeasures
a.Decrease injection pressure.
b.Lower the cylinder temperature setting.
a.Increase the mold draft.
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b.Improve the mold finish.
c.Eliminate undercuts.
d.Use a more appropriate mold temperature. Be mindful of that fact that, in the case of box-shaped
parts, the part will likely stick to the stationary mold if the stationary mold temperature is low.
e.Apply a mold parting agent.
Burn marks
. Description
Discoloration or dark reddish brown streaks in the molded product.
Ⅱ
. Causes
Heat decomposition of the material.
Ⅲ. Countermeasures
a.Lower the cylinder temperature setting.
b.Shorten the intermediate time (dry cycle time).
c.The ram is recessed for too long of a time duration.
d.Slow down injection speed.
a.Provide a larger gas vent.b.Increase the gate sizes.
Product Profile
C...The thing that I like most about using the training programs from Paulson is the fle-ibilit of them.
If an e-truder operator has some down time, the can take a lesson and come back without
interrupting their work schedule. %lso, as problems come up, we use the training to find solutions to
our specific problemsC
Paul )owen * Ticona
;eDre going back to basics in this blog post. Identifing our injection molded part defects is the first
line of defense against wasting valuable molding machine time. 0peaking the same languageF on
the production floor, streamlines communications between emploees and between shifts.
http://www.toray.jp/plastics/en/index.htmlhttp://youtu.be/_jEQmI7t9xIhttp://youtu.be/_jEQmI7t9xIhttp://www.toray.jp/plastics/en/index.html
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The first step to solving injection molded part problems is to identif the problem correctl. The ke to
correctl identifing part defects and communicating about them with co#workers is using the same
terminolog. =ere are some common part problems and part defects that can occur during
production. ;e have used the most common terminolog generall used in the molding industr to
identif the defects. Gor a complete description of molded part problems and how to solve them, ou
can refer to our Injection 7olded Part Problems and 0olutions training course.
Spla+, This defect looks like small silver streaks on
the plastic partDs surface. It is caused b moisture in the plastic raw material that becomes steam
during molding.
Short Shots> 0hort shots are parts where the plastic did not completel fill out the cavit.
Sin- Mar-s, 0ink marks are depressions on the surface of the part. The usuall occur in the thicker
sections of the part.
Flash> Glash is a thin laer of plastic that flows beond the parting line of the mold. Aesides being a
part defect, flash can also permanentl damage the mold and mold parting line.
/eldlines, This is a weldline also called a knitline6. It looks like a scratch on the surface of the part.
It is formed when two plastic flow fronts rejoin in the cavit.
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"etting or /orm Trac-s> % jet or worm track is a surface
appearance defect. @etting occurs during mold filling when a
stream of plastic first shoots through the gate and doesnDt form
a flow front. @etting is reall a mold design problem, but can sometimes be solved b adjusting the
plastic flow rate.
Color Strea-s and Discoloration> =ere is a part that has color streaks. Parts that are not uniform in
color indicate that something is changing in the molding job. Parts can change color because of
defective colorant, a change in the amount of colorant, overheated plastic, or a change in the virgin#
to#regrind ratio.
)urn Mar-s, Aurn marks occur when air, trapped in a cavit, is compressed so much that it ignites.
Aurn marks tpicall occur in the last areas of the cavit to fill.
Part Def ormation or /arpage, =ere is an e-ample of a warped plastic
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part. ;arp is caused b uneven part cooling. Parts can warp either immediatel as the parts are
ejected or take minutes or even hours to warp.
Ejector Mar-s> Ejector marks. 0ometimes undesirable marks are left on the part b the ejection
sstem. If the ejector rods are set up with too much force or if the part is ejected too soon, marks
ma be left on the finished part.
Proper Ginished 7olded Part =andling
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To reduce ccle time, molded parts should be ejected as soon as the are rigid enough to hold their
shape out of the mold. This means that part cooling continues after the parts are ejected. Plastic
parts can warp from uneven cooling in the mold or out of the mold. In general, parts tr to warp
towards the warmer side. %ll parts should be set down to complete their cooling the same wa.
;hen molded parts are scheduled for post#production operations like painting, metallizing or
decorating, the should not be touched with bare hands. The reason is that oils from the skin will
affect the adhesion of the an coating. 1ikewise, optical and medical parts must not be touched for
reasons of appearance and cleanliness. perators should use gloves to handle these tpes of parts
HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
Moulding F in Aritish Gorm of English6 has established a significant place in the manufacturing
industr, mostl as plastic has emerged as the fastest growing construction material in use
toda. Plastic Injection mold design is a complicated part of Injection molding process and
needs to be understood well in order to gain ma-imum benefits from Plastic, as properl designed
plastic parts are fast replacing their metallic and wooden counterparts in almost all industrial and
domestic machiner components. 9ot onl have the successfull replaced huge car parts, such as
panels, bumpers and dashboards, but also fine precision components such as the camera lens
assemblies, including the clear lens itself, and numerous minute watch parts.
assemblies, including the clear lens itself, and numerous minute watch parts.
7odern Engineering plastics such as the 1i"uid 4rstal Polmer 14P6, Polbutlene Terephthalate
PAT6,
Polphenlene 0ulfide PP06, have replaced metallic components in automobile industr due to their
e-cellent strength and mechanical properties, while offering evident reductions in cost and weights
of machiner. ;ith ccle times as low as 5 seconds with both thermoplastics and thermosets,
injection molding has broken the barriers of costs and time limits in modern engineering. 7etallic
parts manufactured b conventional machining or casting processes, took around a few hours of
labor and machining to obtain the finished product of similar levels.
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The above discussion leaves no doubt in our mind as to wh plastic injection molding is emerging
as a clear process of choice over other manufacturing and machining operations. n this site, we
will be discussing about ver important details related to the process and design aspects of injection
mold design. Plastic Injection 7olding Process> Plastic in the molten form is injected or forced b
pressure into a die, known as mold, and held in the mold at a high pressure until the plastic
solidifies. Gor reducing the time re"uired to cool the plastic, cooling channels are provided. ;ater is
circulated through these channels at a decided temperature, which is defined b the plastic resin
being used, and the molding machineDs toggle unit provides the pressure needed to carr out the
operation without an opening of mold halves.
The mold is split into two halves 4ore and 4avit or Gi-ed half or movable half6, sometimes more
0liders and %ngular ejectors or lifters6, depending on the shape of component to be molded. This
splitting provides a means of ejection of parts from mold after complete injection ccle and also
facilitates in the eas machining and replication of shape of part. The 7ore comple- a part is, the
more parting lines are needed to successfull eject it without damaging the part or the mold. If it has
opening or bosses perpendicular to the opening direction of cavit and core, then we need to make
use of sliders or angular ejectors also called as lifters6.
% mold designer has to be conversant with a number of important aspects about mold tooling and
plastic resins. =e needs to be able to clearl distinguish the tpe of resins or plastic material to use
for a specific application and function. =e needs to know which materials or allos to use for making
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the core and cavit of the mold and which ones to use in the manufacturing of the other mold plates
and standard parts such as ejector plates, ejector pins, sprue bush, knockout rods, support pins etc.
Gurther, he needs to have basic understanding of injection molding machines, process, injection
conditions and parameters, part design related aspects such as sink marks and weld lines. It usuall
takes ears of e-perience to become a complete mold designer. 3ue to constant developments in
both, the engineering plastic resins and mold materials, he needs to keep himself updated with the
latest trends and make use of them while actuall designing the molds.
Gor more information related to Plastic Injection 7olding 3esign and Process Tips, bookmark our
site and check back periodicall to get the latest information on plastic parts process and mold
designing tips.
LABELS: INJECTION MOLD DESIGN TIPS, INJECTION MOLDING DESIGN GUIDE, INJECTION MOLDING PROCESS, PLASTIC INJECTION MOLD
DESIGN, PLASTIC INJECTION MOLDING
Most defects in plastic parts can be traced back to three sources:
• The material being used to make the part
• The processing of the material in the mold
• The mold itself
We have grouped the defects together by their most common cause; however one or more factors
may contribute to a defect.
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Common defects linked to the plastic resins or additives being used to manufacture a
part include:
Color streaks – Just like the name implies, color streaks are random areas of color change that are
often attributed to the non-uniform mixing of resins and colorants.
Delamination – This defect appears as a flaky surface layer on the part and is often caused by
contamination or moisture in the resin pellets.
Discoloration - This can occur when the hopper and feed zone have not been flushed properly to
remove any residual color.
Embedded contaminates – Particles or flecks of residual foreign material that can originate in the
barrel of the press.
Splay marks or silver streaks – Circular marks appearing where the molten plastic enters the mold
cavity. This is often caused by excessive moisture in the resin.
Common defects linked to the processing of the plastic resin in the mold include:
Blistering - Bubbles or raised imperfections that are generally caused by too much heat and/or
inadequate cooling.
Burn marks – Black or brown blemishes (which are carbon deposits) that are caused by improper
ventilation or prolonged heating in the mold.
Cold slugs – A small non-uniform area on the part caused by an improperly heated piece of plastic
becoming attached to the part.
Flow marks – A wavy pattern or discoloration caused by a slow injection speed which allows the
material to cool too quickly.
Sink marks or shrinkage voids – Depressions or hollows in a part that can be attributed to
excessive press pressure, non-uniform heating, inadequate cooling time or part design.
Stress cracking or stress crazing – This defect usually occurs as a result of over exposure to a
high temperature.
Stringing – A thin strand of material attached to a part generally caused by a nozzle that is too hot.
Common defects linked to improper mold design and/or maintenance include:
Drag marks – Scratches that occur when the part is ejected from the mold. This is usually due to an
improperly designed ejector system or one that is out of alignment.
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Flash or burrs – A thin lip or protrusion beyond the body of the part that is generally caused by poor
clamping force, improper mold design and/or mold damage.
Jetting –A sna kelike line of material that cools
independently of the material around it. This defect is generally due to poor tool design often relating
to incorrect gate size and length or placement.
Short shot – An incomplete part due to lack of a filled mold. This problem is often attributed to a
blockage or improper injection pressure.
Warping – A part with a distorted shape can be due to a poor cooling system in the mold. When the
plastic material is cooled unevenly, the result is a bowing effect.
Most of the defects listed here can be addressed by making changes to the processing, the material
or the mold itself. The best way to avoid these part defects is to work with a plastic injection
molderthat has a great deal of experience with various resins and their applications. Using a turn-
key manufacturer, who also builds and maintains the mold, can help avoid any costly machining
charges or mold replacement.
Injection moulding injection molding in the ?0%6 is a manufacturing process for producing partsb injecting material into a mould. Injection moulding can be performed with a host of materials,
including metals, for which the process is called diecasting6, glasses, elastomers, confections, and
most commonl thermoplastic and thermosetting polmers. 7aterial for the part is fed into a heated
barrel, mi-ed, and forced into a mould cavit, where it cools and hardens to the configuration of the
cavit.!J>$') %fter a product is designed, usuall b an industrial designer or an engineer , moulds are
made b a mouldmaker or toolmaker6 from metal, usuall either steel or aluminum, and precision#
machined to form the features of the desired part. Injection moulding is widel used for
manufacturing a variet of parts, from the smallest components to entire bod panels of cars.
%dvances in &3 printing technolog, using photopolmers which do not melt during the injectionmoulding of some lower temperature thermoplastics, can be used for some simple injection moulds.
Parts to be injection moulded must be ver carefull designed to facilitate the moulding processK the
material used for the part, the desired shape and features of the part, the material of the mould, and
the properties of the moulding machine must all be taken into account. The versatilit of injection
moulding is facilitated b this breadth of design considerations and possibilities.
http://info.rodongroup.com/blog/bid/93916/Key-Ingredients-to-Achieving-Perfect-Plastic-Parts-0http://info.rodongroup.com/blog/bid/93916/Key-Ingredients-to-Achieving-Perfect-Plastic-Parts-0http://info.rodongroup.com/blog/bid/93916/Key-Ingredients-to-Achieving-Perfect-Plastic-Parts-0https://en.wikipedia.org/wiki/Manufacturinghttps://en.wikipedia.org/wiki/Manufacturinghttps://en.wikipedia.org/wiki/Diecastinghttps://en.wikipedia.org/wiki/Glasshttps://en.wikipedia.org/wiki/Elastomerhttps://en.wikipedia.org/wiki/Thermoplastichttps://en.wikipedia.org/wiki/Thermoplastichttps://en.wikipedia.org/wiki/Thermosettinghttps://en.wikipedia.org/wiki/Injection_moulding#cite_note-manPRG-1https://en.wikipedia.org/wiki/Injection_moulding#cite_note-manPRG-1https://en.wikipedia.org/wiki/Industrial_designhttps://en.wikipedia.org/wiki/Engineerhttps://en.wikipedia.org/wiki/Mouldmakerhttps://en.wikipedia.org/wiki/3D_Metal_Mouldinghttps://en.wikipedia.org/wiki/Steelhttps://en.wikipedia.org/wiki/Steelhttps://en.wikipedia.org/wiki/Aluminumhttps://en.wikipedia.org/wiki/Aluminumhttps://en.wikipedia.org/wiki/Machininghttps://en.wikipedia.org/wiki/Machininghttps://en.wikipedia.org/wiki/Machininghttps://en.wikipedia.org/wiki/Body_panelhttps://en.wikipedia.org/wiki/Automobilehttps://en.wikipedia.org/wiki/3D_printinghttp://info.rodongroup.com/blog/bid/93916/Key-Ingredients-to-Achieving-Perfect-Plastic-Parts-0http://info.rodongroup.com/blog/bid/93916/Key-Ingredients-to-Achieving-Perfect-Plastic-Parts-0https://en.wikipedia.org/wiki/Manufacturinghttps://en.wikipedia.org/wiki/Diecastinghttps://en.wikipedia.org/wiki/Glasshttps://en.wikipedia.org/wiki/Elastomerhttps://en.wikipedia.org/wiki/Thermoplastichttps://en.wikipedia.org/wiki/Thermosettinghttps://en.wikipedia.org/wiki/Injection_moulding#cite_note-manPRG-1https://en.wikipedia.org/wiki/Industrial_designhttps://en.wikipedia.org/wiki/Engineerhttps://en.wikipedia.org/wiki/Mouldmakerhttps://en.wikipedia.org/wiki/3D_Metal_Mouldinghttps://en.wikipedia.org/wiki/Steelhttps://en.wikipedia.org/wiki/Aluminumhttps://en.wikipedia.org/wiki/Machininghttps://en.wikipedia.org/wiki/Machininghttps://en.wikipedia.org/wiki/Body_panelhttps://en.wikipedia.org/wiki/Automobilehttps://en.wikipedia.org/wiki/3D_printing
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