6 - Injection inhomogeneities during packing, sink marks, voids, air bubbles - Smartplast

Contact

+420 725 764 813 olga@smartplast.cz

Company address

SMARTPLAST s.r.o.
B. Němcové 351
760 01 Zlín

Company ID: 28290330
VAT ID: CZ28290330

We are members of professional clusters

Plastikářšký klastr

AUTOKLASTR

Contact

+420 725 764 813 olga@smartplast.cz

Company address

SMARTPLAST s.r.o.
B. Němcové 351
760 01 Zlín

Company ID: 28290330
VAT ID: CZ28290330

We are members of professional clusters

Plastikářšký klastr

AUTOKLASTR

6 – Injection inhomogeneities during packing, sink marks, voids, air bubbles

6 – Injection inhomogeneities during packing, sink marks, voids, air bubbles

Domů / 6 – Injection inhomogeneities during packing, sink marks, voids, air bubbles

Presenter

Ing. Petr Halaška
Smartplast s.r.o.

Sink marks are visible defects on the surfaces of injection-molded parts. A more severe stage are voids, unwanted cavities within the walls of injection-molded parts. They affect both the appearance and mechanical properties of the part. In this webinar, we will show how sink marks and voids form, and how to eliminate them through part design and mold design. We will also look at how sink marks and voids can be successfully predicted using Moldflow analysis to minimize the risk of their occurrence. This webinar is also suitable for users of other analytical software.

Webinar recording

Program

What is a sink mark, how does it form?

What is a void, how does it form, difference between a void and an air bubble?

PVT diagram and the influence of plastic type on void formation

Moldflow prediction of void formation – technological part design

Moldflow prediction of void formation – mold design

CT tomography for scanning voids

Moldflow prediction of void formation – injection molding machine setup

Effect of voids on part strength

Webinar

6 – Injection inhomogeneities during packing, sink marks, voids, air bubbles

Presenter

Ing. Petr Halaška

Other webinars

1 – Injection instability – Rheology, plasticization, homogeneity, degradation, streaks

In this webinar, we will discuss how plasticization affects the quality of the injection-molded part and what visible defects may occur as a result.

2 – Injection instability during cavity filling: orientation, cold welds, trapped air

In this section, we will focus on injection instabilities that arise during the cavity filling phase, which stem from the nature of the plastic melt.

3 – Cavity filling instability, rheology, shear stress, accuracy of Moldflow results, uneven cavity filling

How accurate are Moldflow analysis results? The results are only as accurate as the input data provided.

4 – Cavity filling instability – unbalanced cavity filling – gating system balancing – Melt Flipper

Very often, injection-molded parts have thin walls that are difficult to fill. We will demonstrate the influence of cavity pressure on their filling.

5 – Injection inhomogeneities during packing – shrinkage, anisotropy, tolerance

Sink marks are visible defects on the surfaces of injection-molded parts. A more severe stage are voids, unwanted cavities within the walls of injection-molded parts.

7 – Requirements for accuracy level and tolerances of injection-molded parts, DIN 16742:2013 and ISO 20457:2018

This webinar follows webinar No. 6 Injection inhomogeneities during packing – shrinkage, anisotropy, tolerance.

8 – Cooling – part design – mold construction – mold maintenance

The cost of plastic and cooling time can account for more than 70% of the part production costs.

9 – Design conflicts between part and mold, how to further optimize cooling

The cost of plastic and cooling time can make up more than 70% of the production costs of a part.

10 – What is residual stress, causes of its formation

Residual stresses are mechanical stresses that develop in the injection-molded part during the individual phases of the injection molding cycle.

11 – Effect of residual stress on deformation and part quality

Residual stresses are mechanical, residual stresses generated in the injection-molded part during manufacturing.

12 – Reduction of residual stress effects – part design, mold construction, machine settings

Residual stresses are mechanical, residual stresses generated by internal forces in the injection-molded part during the injection molding cycle.

13 – What influences the formation of voids, analysis of the formation of voids and their removal

Shrinkage cavities are unwanted voids in the walls of injection-molded parts. They affect the appearance of the part as well as its mechanical properties.

14 – Uneven filling of injection mold cavities and how to adjust the filling

Uneven filling of a cavity or cavities in injection molds is a phenomenon that everyone involved in injection molding technology has certainly encountered.

15 – Influence of part design and mold construction on cooling time

The cost of plastic and cooling time often make up more than 70% of the cost of manufacturing a part.

16 – Formation of residual stresses during injection molding and their effects

Residual stresses are mechanical stresses that develop in an injection-molded part due to internal forces. They are generated mainly during the injection molding cycle. These stresses remain embedded in the molded part even after ejection from the mold cavity.

17 – How to reduce residual stresses in an injection-molded part

Residual stresses are mechanical stresses that develop in an injection-molded part due to internal forces.