clamping tonnage VS shot weight,widget for injection molding calculation

plastic mold design

clamping tonnage VS shot weight

clamping tonnage(T-吨)shot weight(g-克)shot weight(oz-盎司)
1070.24
20180.64
30311.1
40481.7
50652.3
60853
701164.1
801284.5
901515.3
1001736.1
1101997
1202247.9
1302508.8
1402789.8
15030710.8
16033511.8
18039513.9
20045716.1
22052318.4
25062822.1
30080928.5
350100335.3
400121042.6
450142650.2
500165358.2
550188966.5
600213375.1
650238684
8503465122
10004374154
12005623198
14006986246
16008435297
18009940350
200011502405

Injection Molding Clamping Force Calculation

ClassPlastic MaterialConstant K
1PS,PE,PPX1.0
2PA,PBT,PETPX1.3-1.35
3CA,CAB,CAP,EVA,PEEL,PPVCX1.35-1.45
4ABS,ASA/AAS,POMX1.45-1.55
5PMMA,PC/ABS,PC/PBTX1.55-1.70
6PC,PES,PSU,PEEK,UPVC,PEIX1.70-1.90

LT-ratio

 

 

 

 

 

 

 

 

chart 1.

 

 

A round PC lamp base with 220mm outter diameter,and the wall thickness range from 1.9-2.2mm,the gate is one drop pinpoint gate.What is the clamping force need for this part?

F=Po*K*S

pic1

S:    S=3.14*22*22/4=380CM^2

P0:  L/T=200/1.9=105:1  [200 is  the longest distance of melt flowing=220/2+90(runner lenght)]

check the chart 1. above,the 105 points to the pressure about 165,so the Po  is 160 bar

K:   PC material ‘s constant K is 1.7-1.9,now we choose 1.9 for safe reason,so

F=160*1.9*380=115.5 ton.

IMG_20140526_100858

 

The L/T ratio:

 1.0mm (thickness)1.5mm (thickness)2.0mm (thickness)2.5mm (thickness)3.0mm (thickness)3.5mm (thickness)4.0mm (thickness)
GPPS<6060-110110-170170-240240-340340-450450-560
HIPS<6060-110110-160160-230230-330330-420420-520
PP<7070-130130-180180-250250-380380-500500-650
PE<8080-150150-220220-300300-430430-580580-700
POM<5050-100100-150150-210210-310310-420420-500
ABS<5050-100100-150150-200200-300300-400400-500
AS<4040-8080-130130-180180-250250-350350-450
PC<3535-7070-110110-160160-200200-280280-370