6.1 Checking M aximum I njection V olume 6.2 Checking I njection P ressure
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6.1 Checking Maximum Injection Volume 6.2 Checking Injection Pressure 6.3 Checking Clamping Force 6.4 Checking Size of Mold Parts 6.5 Checking Mold Opening stroke 6.6 Checking Ejector Chapter Ⅵ Checking Process Parameters of Injection Machine
description
Chapter Ⅵ Checking Process Parameters of Injection Machine. 6.1 Checking M aximum I njection V olume 6.2 Checking I njection P ressure 6.3 Checking C lamping F orce 6.4 Checking Size of Mold Parts 6.5 Checking M o ld Opening stroke 6.6 Checking E jector. - PowerPoint PPT Presentation
Transcript of 6.1 Checking M aximum I njection V olume 6.2 Checking I njection P ressure
6.1 Checking Maximum Injection Volume6.2 Checking Injection Pressure
6.3 Checking Clamping Force
6.4 Checking Size of Mold Parts
6.5 Checking Mold Opening stroke
6.6 Checking Ejector
Chapter Ⅵ Checking Process Parameters of Injection Machine
6.1 Checking Maximum Injection Volume
The actual injection volume should be less than 80% injection machine’s
maximum injection volume
injection volume shown by volume :
V ≤ 0.8Vm
where,
V - Total volume of plastic parts (plastic parts + gating system)
V m - Maximum injection volume of injection machine (cm3)
The injection volume shown by weight:
G ≤ 0.8G m G = p'V
where,
G - The total weight of plastic parts (plastic parts + gating system)
G m - The maximum injection volume of the injection machine (g)
p'- Plastic barrel temperature and pressure density (g/cm3)
6.1 Checking Maximum Injection Volume
6.2 Checking Injection Pressure
Check the Rated injection pressure of injection machine can meet the required pressure or not
P n ≥ P iWhere,P i - The required pressure of plastic molding injectionP n - The nominal injection pressure injection machine
P i will be affected by the gating system, the resistance of the cavity, the m
old temperature and other factors.
When P i is too big: lager flash, demolding difficult, poor surface quality,
and big internal stress
When P i is too small: can not successfully filled cavity, form inadequate
6.3 Checking Clamping Force
Where, F c – The nominal clamping force of injection machine (N) A p – The total projected area of the plastic pieces and pouring system in the parting surface(mm2) q - The average pressure of the plastic melt cavity (MPa)
The clamping force is the maximum force of the clamping device applied to the mold
Fc≥q·Ap
Nozzle size locating hole size
Rod spacing Mold closed thickness
Mounting screw
hole size
6.4 Checking Size of Mold Parts
1.Nozzle size
The spherical radius of gate sets R and the spherical radius of nozzle front end R0Nozzle diameter d0 and gate sets small side hole diameter dRelationship: d = d0 + (0.5-1) mm R = R0 + (1-2) mm
6.4 Checking Size of Mold Parts
2.locating hole size
h: small mold, take (8-10) mm Large mold,take (10-15) mm
6.4 Checking Size of Mold Parts
3.Rod spacing Dimensions of one mold should be less than the rod spacing of the i
njection molding machine to ensure that the mold can be installed on th
e injection machine work table.
6.4 Checking Size of Mold Parts
The relationship between mold size and rod spacing of the injection machine
4.Mold closed thickness
Hmax≥Hm≥Hmin
6.4 Checking Size of Mold Parts
5.Mounting screw hole size
Mold lighter weight using plate fixed
Mold heavier weight using screw fixed
6.4 Checking Size of Mold Parts
Single-parting surface mold: S> = H1 + H2 + (5 ~ 10) mmDouble-parting surface mold: S> = H1 + H2 + a + (5 ~ 10) mm
6.5 Checking Mold Opening stroke
Checking opening stroke of single-parting mold
1-Fixed mode 2-Dynamic model
Checking opening stroke of double-parting mold1-Fixed mode 2-Flow plate 3-Dynamic model
maximum stroke of mold opening of injection machine(S) is independent of mold thickness (Hm)
6.5 Checking Mold Opening stroke
maximum stroke of mold opening of injection machine(S) is independent of mold thickness (Hm)
Single parting surface mold: S0 = Hm + [H1 + H2 + (5 ~ 10)]
Double parting surface mold : S0 = Hm + [H1 + H2 + a + (5 ~ 10)]
6.5 Checking Mold Opening stroke
Stroke checking of hydraulic clamping part
maximum mold opening stroke of side parting core-pulling mechanism (S)
When H4 in> H1 + H2,
S = H4 in (5 ~ 10) mm
When H4 in <H1 + H2,
S = H1 + H2 + (5 ~ 10) mm
6.5 Checking Mold Opening stroke
6 .6 Checking Ejector
center eject
Sides dual mechanical eject
center hydraulic eject and side dual mechanical ejector
center eject and auxiliary fuel tank
classification of ejector :
Vertical injection machine
Horizontal injection machine
Right-angle injection machine
calculation of injection machine
Thinking and Practice
XS-ZY-500 ： means the injection machine with a maximum injection volume
of 500cm3
XS ： Plastic molding machine Z ： Injection machine Y ： Screw
S-ZY-190/90 ： The injection volume is 190cm3 、 Clamping force is 90t
SYS-30 ： means the vertical injection machine with a injection volume of
30g
