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发表于 2007-3-30 08:16:27
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来自: 中国台湾
加熱工藝條件設定' e: g) T# W9 `1 @, P
Heating technique parameter setting1 b8 r5 t' Y Z* p5 S. @
1.加熱段溫度設定必須按照産品所使用的原料的不同而不同,但却必須遵循一個這樣的規則,即由射口筒到進科段溫度是逐步遞减的.且遞减溫度是以10.度爲單位.
0 X k7 l4 B5 S9 v( XThe proper temperature setting differs depending on type of resin % [( ]5 s5 O6 ~$ d4 ~; r* W) X
material, but it must be abide by a rule that temperature setting should + U. j: L: |: b- g
diminish in step 10.C from nozzle to feeding resin material position.
3 _9 Q' S4 g! P# z2特殊情况下.如料頭抽絲,則射口筒溫度應降低,如果是比較特殊的原料冷凝比較快的.則射口筒溫度則不止比第二節法蘭溫度高10度.比如PPS. 5 i% H6 \: w" l9 d4 u
尼龍等." E; ]2 {9 T; \% o, }4 F. M0 a/ x
Nozzle temperature setting should low if product line. If resin
( @$ W1 e9 S. R9 B d, J) K) Pmaterial such as PPS, PA, cool very soon , Nozzle temperature should higher
3 J D; h+ N" c# j6 t7 Q7 Ymore 10.C than the second cylinder temperature.
" [4 w/ d7 _) s3 @4 m9 ~3 d; H* k3.機台馬達啓動溫度視乎機台不同而不同,一般出于對機台油路中的油封保護需要,油溫最好能控制在40度-60度,以免油封長期高壓而變化,縮短使用壽命,造成成型不穩定.: d6 \ f. w4 n
Pump turning on temperature is different depending on type of injection
) k& h) U7 O. }5 h6 F: Amolding machine. To protect oil seal of machine it set oil temperature
* e& x- \, d1 c+ B1 Y- U- o1 {第三節注射及熔膠(加料)工藝條件設定* J! m6 |" k1 I: Y
Injection and plastic Technique parameter setting
' M% w3 F# w2 m一.注射
) N l2 i5 I% l% I2 RInjection
; ^; d. L& k: M注射是把塑料原料經加熱後射進模腔的過程,它一般可分爲第一級,第二級,第三級,第四級及保壓幾段:8 f$ i: }& G r% x
Injection is a step which inject melt resin material into mold. It
. z) W2 M- [1 Xconsists of stepl,step2 ,step3,step4 and holding pressure step:
* u! p' B( A9 b- D3 }: V s1.第一級注射一般是注射料頭段.具注射量一般可根據料頭的輕重來估計其行程,當然也可以依據公式來計算,如公式:3 H3 G9 O+ o$ D
Step l injects usually tunnel material, Injection Volume can be
! q3 ]6 b N% @estimated according to the weight of course it can be calculated by formula:5 A3 v, J( @9 S7 z" X
L=Si=Vi/0.785Ds2
2 }% C% b& e/ SL:注射行程; Si: 注射行程;) _9 p& S' Z6 \+ \* e( a" [4 ~. n
L: injection stroke Si: injection stroke$ |$ s) w7 g O& M
Vi:理論注射容積; Ds:螺杆直徑;
& P6 _# {! M' F2 C# kVi: injection volume of theoretical Ds: diameter of screw
4 @. K+ A3 A# x b3 |7 k' N! I7 t0.785:是Ω/4的值.. I; z: X' z' g3 M
0. 785: value of Ω/4.
# R9 N3 f# U/ f/ L3 S$ V5 G$ L8 q當然,如果我們在成型時每設定一個參數都要計算一次,要成型出一個産品就要幾個小時才能完成了.
E$ Q/ E# ?6 C0 N8 X6 z' pBut it cost a lot of time to produce one product if every time molding
5 r" |8 |* D# e. Yparameter is setting by calculation., P& \- e6 U7 N) `; P
2.第二級是注塑産品約2/3的階段,當然,根據産品特殊需要,也允許成型不到2/3階段,比如避免結合綫問題,這一階段的成型速度及壓力一般是整個成型段的最大值段,如果排的産品與機台基本是相吻合的.模具結構合理,排氣良好,這一段的壓力一般也不會超過80%.速度側視産品需變,可能大到95%也可,自然一般都是在55%-80%間.
3 Z1 I; g& j# r& Z# fStep 2 inject 2/3 of product. It can lower 2/3 of product according to ; }, a0 \7 Z9 ~/ e' I8 W
requirement of product. For example to prevent weld line. Molding speed : O- t1 ~5 r4 Z4 |3 x# M2 V: R6 V
and pressure on this step is the maximum of whole molding section. If
M5 i/ l5 w) A" C8 l% oMold suit the injection molding machine and mold structure reasonable
: B$ K' C! c* e4 jand eject air well, pressure of this step should lower 80%. Molding speed 5 x; S$ \8 C8 V: p' v
setting within 55-80% but it may setting 95% for especial product.
$ N3 P/ |- ?# F8 m f. {1 ?3.第三段是注射餘下的1/3段,其速度和壓力根據産品的需要,一般是小于第二段,速度和壓力存在于一個往下降的過程.主要是爲了防止産品毛邊的産生,但同時又必須把産品充填飽滿.0 z7 m6 ]# G# b% D+ E: l% b
Step3 inject remain 1/3 of product. According to product molding speed
6 P4 B2 o/ Y1 y1 f) {" J1 M) Kand pressure lower than that of step2 To prevent flash speed and
9 m1 `: i* E: `pressure should decrease but it can’t shot short.
7 D5 b4 ]0 Y$ U$ k) J4.第四段:一般有機台還有第五,第六段,這段的成型速度和壓力相同前,都存在兩段一個遞减過程.其作用都是起到一個再次充滿的作用.2 v4 I9 e0 p/ ^4 Z
Step4 section: Some injection machines have step5,step6 which are same 5 `7 l0 j0 H4 y7 b
as former molding speed and pressure this step should diminish and
5 C8 ]8 g( r, }inject once more.$ N2 c% I# s* l2 S# n- h, i
5.保壓段:不論成型什麽産品,都存在一個保壓過程.任何産品都不同程度的存在一個厚薄不一的問題,正常情况下,較厚的部分都可能存在一個收縮凹陷的現象,爲了解决這種現象,就應應用到保壓,保壓一般來講都應用較慢的射速,而壓力的設置則應看縮水的情况如何,小到25%,大到80%都有可能.4 |6 B3 @* @% Q- \
Holding pressure step: No matter what product there is a holding 3 J5 K3 I1 G U( J. ^* E( B; l/ h
pressure step. Any product can’t molding a same thickness. Usually the / Q. |0 A" N# i6 t" G
deeper section may sink mark . To prevent this defect it should set holding
& ]% p1 v( s! r" }' Hpressure, The injection speed of holding pressure step is slow but
' R3 w3 G& \$ F" J8 bholding pressure setting within 25-80% depending on sink mark9 {' f4 v7 r7 J3 S9 w* ~
' P) A, ?! q) ]. `5 `& lwithin 40.C-60.C, If oil seal work on condition that high pressure and
1 @' g0 j0 B0 e; g+ udamaged It’s work time will be shorter, it can cause molding stable.
2 s6 Y& L5 i) N2 s二.熔膠段工藝# F9 j9 o5 r, f7 m( ?
Plastic Technique
+ j2 B4 l9 n' N+ S$ T+ U1.再複雜的熔膠旋轉過程最多不會超過三段,因爲熔膠本身就是存在于把膠熔進料筒的過程,如果原料粘度大,熔膠壓力則大,但速度則應取决于原料的分解溫度,熔膠速度越快,原料中的剪切力則會越大,料管溫度則越高,局部原料産生分解的可能性則會越大,故一般熔膠會采用中速爲宜,如45%-75%,熔膠同時會碰到一個比較重要的環節,那就是背壓的使用,産品精度要求越大,背壓的使用則更大,背壓可使原料分子間結構更緊密,成型出的産品則尺寸更穩定,外觀越好.當然,背壓太大,則會産生流涎,所以背壓的使用又應考虙到其它原因./ p9 v8 ]; w3 x
Plastic should lower 3 steps, because plastic is a step to add melt
$ Q! D3 `: E5 `: [2 d8 {9 N8 B, yresin material to cyclinder , Higher stick of resin material ,higher screw . W& ~% |) K& G8 B9 O
back pressure. Screw speed differs depending on decomposing temperature
: y8 G: C( u) I+ ^. J9 i$ Wof resin material ,Higher screw speed ,Higher trim force of resin,
- ^* W8 J/ A r( _& Ihigher cyclinder temperature. Some resin material may decomposes so it set
1 {& H- D" M, r$ m5 X# U3 l; Mscrew speed in mid-speed such as 45-75%, In plastic step setting screw
$ h5 s+ ^( \6 Iback pressure is very important, Higher screw back pressure ,higher
0 e4 x" N ~) V. E! t8 jquality of product screw back pressure make resin structure order, Molding
- m3 d# f/ I* ^product is beautiful and volume stable. But ,it maybe flow if screw
5 @3 I2 Y. U# C1 \7 oback pressure too high . So all factors should be considered when using
2 S% O) E) y# y `. Y' G iscrew back pressure.
+ W; K, @. h, c6 U: A. m0 C2.熔膠過程還有一個比較重要的環節,那就是松退,松退分前松退和後松退,其作用一般是爲了防止流涎和抽絲,設定值速度和壓力都在20%-50%間,設定的行程一般在2-5cm間,太長的行程可能會使料筒裏面貯存空氣,導致下一模出現不期望的氣泡.
8 j y- k0 d* lIn plastic step sucking back is very important too. Sucking back $ r7 i! T7 n" L6 s' ^0 J8 b. e
include front sucking back and back sucking back It setting sucking back to
. ^# z4 r6 X _* A% E; lprevent flow and line. It sets sucking back speed and pressure within 7 m8 n i" B/ b3 A! P& \
20-50% and distance within 2-5cm. TOO long distance make cyclinder 8 |* r' e: P, u" H+ z
reserve air and cause bubble at next molding. |
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