Transcript Cover Side Cooling Lines

High Production Rate Tooling
Case Western Reserve University
David Schwam
John F. Wallace
Castings for Improved Defense
Readiness
NADCA DMC February 2008
Chicago, IL
Objectives
• Production rate determines profitability of metal mold
processes. Increasing production rate is therefore a
high priority, boosting profits and competitiveness.
• A key aspect of increased production rate is shorter
cycle times by faster removal of heat from the casting.
• Advances in modern die steels should allow more
aggressive use of cooling line size and distance from the
cavity.
• The project will evaluate effectiveness of new cooling
line design and provide guidelines that account for
higher strength and toughness of advanced die steels.
Needs & Benefits
Benefits to:
• DoD
– Shorter production lead times and lower cost
parts for DoD weapon systems
• Industry
– Increased profitability and competitiveness
of metal mold casting industry
Process Specifications
IN SIMULATION THIS
OCCURS AT THE SAME TIME.
Spray time is:
(5) Seconds on large
inserts
(3) seconds on cores
Some additional
time:
(5) seconds
blow off
(2) seconds wait
Cover Side Cooling Lines – V4
Cover Cores
Green shows cooling
line bubblers in cores.
Material Water
Oil lines 157 ºC (300 –325 ºF)
Flow rate of 0.34 m3/hr (1.5
gal/min)
HTC of 500 W/m2K
Water line run at 20 ºC
Flow rate of 0.7 m3/hr. (3.0 gal /
min)
HTC of 5500 W/m2K
Shot tip - HTC of 10000 W/m2K
Cover cooling lines.
Shot Tip cooling Material - Oil
Material –
Water Not
shown
Die Steel initial temp
300 ºC (600 º F)
Ejector Side Cooling Lines V4
Green shows cooling
line bubbler in ejector
inserts. Material
Water
Oil lines 157 ºC (300 –325 ºF)
Flow rate of 0.34 m3/hr (1.5
gal/min)
HTC of 500 W/m2K
Water line run at 20 ºC
Flow rate of 0.7
min)
m3/hr.
HTC of 5500 W/m2K
(3.0 gal /
Ejector Runner block Ejector cooling lines.
cooling lines.
Material - Oil
Material - Water
Die Steel initial temp
300 ºC (600 º F)
Section Though Die
Current
Design
Cover core bubbler
lines.
A= 0.87”
B= 0.69”
Cover die cooling lines
A
0.30”
COVER SIDE
EJECTOR SIDE
B
0.50”
Thermocouple placed
in center of the part
spaced ½ way
between the cores
(length wise).
Ejector die bubbler
lines.
Ejector die bubbler
lines.
Part during solidification V4 (open die at 30 sec.)
Click on image
Section though the die steel during solidification V04
Click on image
Thermocouple Result During Cycle V04
At 30 seconds
thermocouple is
545.6 C
Cover Side Cooling Lines – V5
Cover Cores
Green shows cooling
line bubblers in cores.
Material Water
Oil lines NONE
Water line run at 20 ºC
Flow rate of 0.7 m3/hr. (3.0 gal / min)
HTC of 5500 W/m2K
Shot tip - HTC of 10000 W/m2K
Cover cooling lines.
Shot Tip cooling Material - Water
Material –
Water Not
shown
Die Steel initial temp
150 ºC (300 º F)
Ejector Side Cooling Lines - V5
Green shows cooling
line bubbler in
ejector inserts.
Material Water
Oil lines NONE
Water line run at 20 ºC
Flow rate of 0.7 m3/hr. (3.0 gal
/ min)
HTC of 5500 W/m2K
Ejector Runner
block cooling lines.
Material - Water
Ejector cooling
lines. Material Water
Die Steel initial temp
150 ºC (300 º F)
Section Though Die
Cover core bubbler
lines.
Modified
Design
A= 0.50”
Cover die cooling
lines
B= 0.50”
A
0.30”
COVER SIDE
EJECTOR SIDE
B
0.50”
Thermocouple
placed in center of
the part spaced ½
way between the
cores (length wise).
Ejector die bubbler
lines.
Ejector die bubbler
lines.
Thermocouple Result During V05
•V5 was run with
these conditions.
•Initial Die Steel
initial temp 150 ºC
(300 º F)
•A and B dimensions
changed to 0.500
23.9 sec
•A & B lines run
with water.
Oil (V04) vs. Water (V05) Comparison
Predicted cycle time reduction: 6.1/30=20%
V04 with Oil
TC = 545.6 C @ 30 sec
V05 with water
TC = 545.6 C @23.9 sec
Project and
Implementation Plan
• Fabricate and test die casting inserts with larger
cooling lines and/or closer to the casting.
• Monitor production of parts and determine new cycle
time.
• Evaluate effect of modified cooling line system on die
life.
• A good baseline for the study is available from
extensive database of previous production.
• Results will be disseminated through NADCA
meetings, NADCA publications for industry, and the
Metalcasting Congress
Acknowledgements
• AMC’s Castings for Improved Defense
Readiness program is sponsored the
Armaments Research and Development
Engineering Center, Picatinny, NJ and
Benet Laboratories, Watervliet, NY.
• The support of St. Clair Die Casting is
gratefully acknowledged.
High Production Rate Tooling
DLA - POC: Dan Gearing ([email protected], 703-767-1418)
Warfighter Relevance: Increased productivity of metal mold components for weapon systems
•
Problem: High cycle times in the production of metal
mold castings
Objective: Evaluate advanced cooling techniques for
casting dies in order to reduce cycle times for metal
mold castings
Benefits: 10% reduction in cycle time associated with
the production of a die casting
•
•
• Reduced production lead time
• Improved productivity
• Reduced operating costs
Partners:
– Case Western Reserve University,
NADCA, St. Clair Die Casting,
Premier Tool & Die Casting
•
Milestones / Deliverables
–
Revised guideline for cooling line placement
•
Transition Plan
–
The revised guidelines will be added to the NADCA Die
Cooling Systems Engineering Course and accompanying
text