moldflow/moldex software objective questions

mold flow software related objective questions

1. Moldflow Set A
Will be reviewed
Image 1.
Which of the following flow patterns is/are considered as completely balanced? *
1

2. Image 2.
Image 3.
All of the above.
Will be reviewed
Weld line and sink mark
Flash and warpage
Short shot and burn mark
Void and jetting
Which defect is related to venting? *
2
Will be reviewed
Which one will induce warpage in the part? Multiple choice *
3

3. Fiber orientation
Differential cooling
Crystallization
All of the above
Will be reviewed
The purpose is to reduce stress concentration
Aesthetics and safety are also considered for the design
The bigger the size the better it is
Radius and chamfer can also effect the part strength
Which one is FLASE about radius and chamfer? *
4
Will be reviewed

4. Gate location 1
Gate location 2
Both location 1 and location 2
None of the above
In the following figure, which gate location would have better pressure uniformity in the part?
*
5
Will be reviewed
T1 – High FFV.
T2 – High FFV.
T1 – Low FFV.
T2 – Low FFV.
For constant flow rate what will be the flow front velocity @ t1 and t2? Multiple choice *
6

5. Will be reviewed
Increase with increase in part thickness
Decrease with increase in part thickness
Remains constant irrespective of the change in part thickness
None of the above
How injection pressure will vary with change in part thickness? *
7
Will be reviewed
The deeper the depth of texture, the larger the draft angle should be
The lack of the draft angle can easily lead to scratches on the part
Both ‘a’ and ‘b’ are true
Which one is TRUE about draft angle for the part with texture? Multiple choice *
8

6. None of them
Will be reviewed
Flow balance
Melt temperature
Packing effect
Appearance
The gate location is decided without the need to consider: *
9
Will be reviewed
Increase with increase in melt viscosity
Decrease with increase in melt viscosity
How “Injection pressure” will vary with change in “Melt viscosity”? *
10

7. Remains constant irrespective of the change in melt viscosity
None of the above
Will be reviewed
It is usually a Newtonian fluid
The shear thinning phenomenon is usually present
Flow resistance is related to flow rate
It has viscoelastic properties
Which one is FALSE about the flow behavior of thermoplastics? *
11
Will be reviewed
To increase packing effect
Purpose of setting multi-stage injection profile? *
12

8. To reduce volumetric shrinkage
To Improve cooling efficiency
To maintain uniform flow front velocity
Will be reviewed
Sudden change in wall thickness is a good design practice
Maintaining uniform thickness is a good design practice
Any acute angle is unfavorable
The suggested length for the transition region is equal to the thickness difference
Which is FALSE about the design of wall thickness in the transition region? *
13
Will be reviewed
Angle <135° = Meld line.
Identify weld line and meld line. Multiple choice *
14

9. Angle >135° = Meld line.
Angle <135° = Weld line.
Angle >135° = Weld line.
Will be reviewed
Short fill time require high pressures because the flow rate is too high.
Long fill time require high pressures due to cooling effect.
Short fill time require high pressures because the flow rate is too slow.
All of the above.
Why pressure vs time plot is U shaped? Multiple choice *
15
Will be reviewed
How to decide gate size for any part? Multiple choice *
16

10. For manually trimmed gates, the gate thickness can be the same as the gated wall thickness.
For automatically trimmed gates, the gate thickness is typically less than 80% of the gated wall thickness.
Refer shear rate plot to define gate size more accurately for any given material.
All of the above.
Will be reviewed
Low molecular orientation and low viscosity
Low molecular orientation and high viscosity
High molecular orientation and low viscosity
High molecular orientation and high viscosity
The melt in shear layer experiences? *
17
Will be reviewed

11. Small molecule fluids are generally (although not exclusively) Newtonian fluids
Viscosity does not change with shear rate
Viscosity does not change with temperature
The viscosity is temperature-dependent
Which one is FALSE about Newtonian fluids? *
18
Will be reviewed
It is recommended to add gates if the flow length ratio exceeds 100
The smaller the value, the easier is the filling of the part
The larger the value, the easier is the filling of the part
If the flow length ratio is greater, the use of plastic material with higher flow ability needs to be considered
Which one is FALSE about flow length ratio for part design? *
19

12. Will be reviewed
Sink mark is caused by wall thickness difference
Wall thickness difference can also cause void
The thickness of the rib should be equal to that of the part
Rib spacing is recommended to be at least 2 times that of part thickness
Which one is FALSE about wall thickness difference? *
20
Will be reviewed
Fountain flow
Shear heating
Melt freezing
What effect will increase with high injection speed? *
21

13. Crystallization
Will be reviewed
When two melt fronts meet and one of them reverses it’s flow direction.
Poor part quality, both visual and structural.
Velocity vectors parallel to fill time contours is the sign of identification of underflow effect.
All of the above.
What do you understand by underflow and it’s effect? Multiple choice *
22
Will be reviewed
Increase with increase in flow length
Decrease with increase in flow length
How “Injection pressure” will vary with change in “Flow length”? *
23

14. Remains constant irrespective of the change in flow length
None of the above
Will be reviewed
Should avoid placement in the visible surfaces
Should be placed at the thinner wall thickness region
Should be placed at the thicker wall thickness region
Should consider no of gates based on l/t ratio
Which one is FLASE about gate location? *
24
Will be reviewed
abcde
A cycle of injection molding contains stages such as (a) Filling, (b) Packing, (c) Cooling, (d)
Mold opening, (e) Mold closing. These stages in sequence are: *
25

15. abced
acbde
aebcd
Will be reviewed
Should have balanced filling.
Pressure drop (Part + Runner) ≤ 75% of the machine capacity.
Should have no hesitation, underflow effect, unwanted weld lines & air traps on front surface.
All of the above.
How to decide gate location and no of gates required for any part? Multiple choice *
26
Will be reviewed
Which of the following statement(s) are correct? Multiple choice
27

16. Image1 - Less accurate results & Low computation time.
Image1 - More accurate results & Low computation time.
Image2 - Less accurate results & High computation time.
Image2 - More accurate results & High computation time.
Will be reviewed
A
B
C
All of the above
Which area has the highest possibility to induce sink mark? *
28
Will be reviewed
Which all are considered as the balanced cavity layout? *
29

17. 1 & 2
2 & 3
1 & 3
None of the above
Will be reviewed
Change gate location
Increase runner diameter
Increase gate size
Using multi-stage pack profile
How to change weld line position? *
30
Will be reviewed

18. Metering Stroke
Filling velocity
Viscosity
Packing pressure
Which is not the control parameter of the injection-molding machine that needs to stabilize? *
31
Will be reviewed
Fountain flow
Shear flow
Laminar Flow
Turbulent flow
Melt flow behaviour is called as? *
32

19. Will be reviewed
Core layer
Frozen layer
Shear layer
Weld line
The melt cools off to form an immobile boundary layer after it contacts the mold wall, and that
is referred to as: *
33
Will be reviewed
a
b
c
In the given figure, which one is the gate? *
34

20. d
e
f
Will be reviewed
Gate location
Gate size
Runner size
All of the above
To improve flow imbalance in single cavity mold, we can revise; *
35
Will be reviewed
Which one is FALSE about wall thickness design? *
36

21. Make sure that the product is manufacturable
The flow length ratio must always be greater than 100
Uniform thickness design can achieve more uniform volumetric shrinkage
The fillet radius is designed to unsure a more uniform stress distribution
Will be reviewed
Viscoelasticity of material
Heat expansion
Compressibility
Heat conductivity
What is the main reason for flow instability of the melt? *
37
Will be reviewed
Which one is not preferred gate location and why? Multiple choice *
38

22. Gate near thin rib.
Gate far from thin rib.
Polymer prefers low resistance path.
Both are not preferred gate location.
Will be reviewed
Gate size
Runner size
Both ‘a’ and ‘b’
None of the above
To improve cavity balancing, we can revise; *
39
Will be reviewed

23. A smaller draft angle can reduce the demolding resistance
When there is texture in the appearance, the draft angle need to be higher.
The draft angle is generally designed as 1~2°.
The draft angle on the cavity side should be more than that of core side.
Which one is FALSE about draft angle? *
40
This content is created by the owner of the form. The data you submit will be sent to the form owner. Microsoft is not responsible for the
privacy or security practices of its customers, including those of this form owner. Never give out your password.
Microsoft Forms | AI-Powered surveys, quizzes and pollsCreate my own form
Privacy and cookies | Terms of use