This document discusses how 3D printing could influence after-sales service operations through printing spare parts. It begins by defining 3D printing and describing the different types of 3D printing processes. It then explores potential applications and benefits of 3D printing for spare parts in after-sales service supply chains, such as reduced costs, improved responsiveness, and postponement. The document proposes a process for identifying promising spare parts for 3D printing by relating part attributes to improvement potentials, incorporating company goals, and calculating an overall ranking. It provides examples of applications at a aerospace company and army that have identified over 1,000 feasible business cases for 3D printing spare parts.

1. SERVICE LOGISTICS IN 3D:
HOW 3D PRINTING OF SPARE PARTS COULD INFLUENCE YOUR FUTURE
AFTER-SALES SERVICE OPERATIONS
Nils Knofius

2. SINTAS PROJECT
SUSTAINABILITY IMPACT OF NEW TECHNOLOGY ON AFTER SALES SERVICE SUPPLY CHAINS
Technological
options with 3D
printing
Failure behavior
& maintainability
Inventory control
policies
Supply chain
network design
10/6/16 2n.knofius@utwente.nl

3. 10/6/16n.knofius@utwente.nl 3
3D PRINTING: HOW IS IT DEFINED?
“Process of joining materials to make objects
from 3D model data, usually layer upon layer”

4. 3D PRINTING: WHAT IS IT?
THERE IS NOT ONLY ONE 3D PRINTING PROCESS
10/6/16 4n.knofius@utwente.nl
Laser
Source
Scanner
System
Powder Delivery
system
Build
Chamber
Digital Light ProcessingPowder Bed Fusion
Roller

5. 10/6/16 5
3D PRINTING: WHAT CAN BE DONE?
Organics
Ceramics
Polymers
Metals
Micro print
Nano print
Large scale print
Materials
Size
Normal size print
n.knofius@utwente.nl
Composite materials

6. 10/6/16 6
3D PRINTING: WHEN IS IT CONSIDERED USEFUL?
n.knofius@utwente.nl
Costs
Production volume
3D printing
Conventional
production
Costs
Geometric complexity
3D printing
Conventional
production

7. POSSIBLE APPLICATIONS IN AFTER-SALES
SERVICE LOGISTICS

8. 10/6/16 8
3D PRINTING IN AFTER-SALES SERVICE SUPPLY CHAINS
THE MAGIC FORMULA?
n.knofius@utwente.nl

9. 10/6/16 9
REASONS FOR 3D PRINTING IN PRACTICE
Design improvements:
1) Weight reduction
2) Waste reduction
3) Improved heat distribution
4) Reduced flow resistance
5) Customization
90% disturbance
force reduction by
flow optimization
with 3D printing
n.knofius@utwente.nl

10. 10/6/16 10
REASONS FOR 3D PRINTING IN PRACTICE
Possible reasons for not observing more applications for after-sales
service supply chains:
1. Bottom-up approach for identifying business cases
2. Engineer-driven implementation of 3D printing
n.knofius@utwente.nl
Prioritize spare part assortment from an after-sales
service supply chain perspective to support identification

11. 10/6/16 11
REASONS FOR 3D PRINTING IN PRACTICE
Possible reasons for not observing more applications for after-sales
service supply chains:
1. Bottom-up approach for identifying business cases
2. Engineer-driven implementation of 3D printing
n.knofius@utwente.nl
Prioritize spare part assortment from an after-sales
service supply chain perspective to support identification

12. 10/6/16 12
IMPROVEMENT POTENTIALS OF 3D PRINTING
FOR AFTER-SALES SERVICE SUPPLY CHAINS
n.knofius@utwente.nl
1) Reduce manufacturing / order costs
2) Reduce direct part usage costs
3) Reduce safety stock costs
4) Improve supply chain responsiveness
5) Reduce effect of supply disruptions
6) Postponement
7) Temporary fix

13. 10/6/16 13
IMPROVEMENT POTENTIALS OF 3D PRINTING
FOR AFTER-SALES SERVICE SUPPLY CHAINS
n.knofius@utwente.nl
1) Reduce manufacturing / order costs
2) Reduce direct part usage costs
3) Reduce safety stock costs
4) Improve supply chain responsiveness
5) Reduce effect of supply disruptions
6) Postponement
7) Temporary fix

14. REDUCE EFFECT OF SUPPLY DISRUPTIONS
10/6/16 14
Regained supply continuity:
 Reduced
obsolescence risk
 Reduced stock-out risk

15. 3D PRINTING IN AFTER-SALES SERVICE SUPPLY CHAINS
PRINT ON DEMAND
Manu-
facturing
Assembly DistributionEngineering
ETO
(engineer-to-order)
MTO
(make-to-order)
ATO
(Assemble-to-order)
MTS
(Make-to-stock)
DFS
(Deliver from local stock)
Push
Forecast driven
Pull
Order driven
CODP
10/6/16 15
Moving the Customer Order Decoupling Point (CODP) with 3D printing:
 Less inventories
 More Flexibility
Production strategies:
n.knofius@utwente.nl

16. TEMPORARY FIX
10/6/16 16n.knofius@utwente.nl
Concept US Army’s Mobile Parts Hospital

17. IDENTIFYING PROMISING SPARE PARTS FOR 3D
PRINTING

18. 10/6/16n.knofius@utwente.nl 18
RELATE SPARE PART ATTRIBUTES TO IMPROVEMENT
POTENTIALS
Improvement potential
Reduce
manufacturing/
order costs
Reduce
direct part
usage costs
Reduce
safety
stock costs
Improve
supply chain
responsiveness
Postponement Temporary
fix
Reduce effect
of supply
disruptions
Sparepartattributes
Demand rate Low Low Low
Resupply lead time Long Long Long Long
Agreed response time Short Short Short
Remaining usage period Long
Manufacturing/ order costs High
Safety stock costs High High
Number of supply options Few Few Few
Supply risk High High

19. 10/6/16 19
INCORPORATE COMPANY GOALS
n.knofius@utwente.nl
Company goals
Reduce
downtime
Secure
supply
Reduce
costs
Supply options
17%
Manufacturing/
order costs
Supply option
26.5% 10.5%
Supply risk
39% 37% 24%
Remaining
usage period
Supply risk
22% 7.5% 16.5%
TWO STAGE ANALYTICAL HIERARCHY PROCESS (SIMPLIFIED EXAMPLE)
Spare part attributes Weights
Supply options 17% + 26,5% = 43,5%
Supply risk 22% + 10,5% = 32,5%
Remaining usage period 7,5%
Manufacturing/order costs 16,5%
Step 1:
Pairwise-comparison
company goals
Stage 2:
Pairwise-comparison
attributes
Resulting weights:

20. 10/6/16 20
INCORPORATE COMPANY GOALS
n.knofius@utwente.nl
Company goals
Reduce
downtime
Secure
supply
Reduce
costs
Supply options
17%
Manufacturing/
order costs
Supply option
26.5% 10.5%
Supply risk
39% 37% 24%
Remaining
usage period
Supply risk
22% 7.5% 16.5%
TWO STAGE ANALYTICAL HIERARCHY PROCESS (SIMPLIFIED EXAMPLE)
Spare part attributes Weights
Supply options 17% + 26,5% = 43,5%
Supply risk 22% + 10,5% = 32,5%
Remaining usage period 7,5%
Manufacturing/order costs 16,5%
Step 1:
Pairwise-comparison
company goals
Step 2:
Assign attributes and
pairwise-comparison
attributes
Resulting weights:

21. 10/6/16 21
INCORPORATE COMPANY GOALS
n.knofius@utwente.nl
TWO STAGE ANALYTICAL HIERARCHY PROCESS (SIMPLIFIED EXAMPLE)
Improvement potential
Reduce
manufacturing/
order costs
Reduce
direct part
usage costs
Reduce
safety
stock costs
Improve
supply chain
responsiveness
Postponement Temporary
fix
Reduce effect
of supply
disruptions
Sparepartattributes
Demand rate Low Low Low
Resupply lead time Long Long Long Long
Agreed response time Short Short Short
Remaining usage period Long
Manufacturing/ order costs High
Safety stock costs High High
Number of supply options Few Few Few
Supply risk High High
= reduce costs = reduce downtime = Secure supply

22. 10/6/16 22
INCORPORATE COMPANY GOALS
n.knofius@utwente.nl
Company goals
Reduce
downtime
Secure
supply
Reduce
costs
Supply options
17%
Manufacturing/
order costs
Supply option
26.5% 10.5%
Supply risk
39% 37% 24%
Remaining
usage period
Supply risk
22% 7.5% 16.5%
TWO STAGE ANALYTICAL HIERARCHY PROCESS (SIMPLIFIED EXAMPLE)
Spare part attributes Weights
Supply options 43,5% (17% + 26,5%)
Supply risk 32,5% (22% + 10,5%)
Remaining usage period 7,5%
Manufacturing/order costs 16,5%
Step 1:
Pairwise-comparison
company goals
Step 2:
Assign attributes and
pairwise-comparison
attributes
Resulting weights:

23. 10/6/16 23
BASIC TECHNOLOGICAL CONSTRAINTS
n.knofius@utwente.nl
Organics
Ceramics
Polymers
Metals
Micro print
Nano print
Large scale print
Materials
Size
Normal size print
Composite materials

24. 10/6/16 24
BASIC TECHNOLOGICAL CONSTRAINTS
n.knofius@utwente.nl
Polymers
Metals
Micro print Materials
Size
Normal size print

25. 10/6/16 25
CALCULATE RANKING OVER ALL SPARE PARTS
Procedure:
Assess technological constraints:
a) If any technological constraint not fulfilled: 𝐼𝑡𝑒𝑚 𝑠𝑐𝑜𝑟𝑒 =
b) Otherwise: 𝐼𝑡𝑒𝑚 𝑠𝑐𝑜𝑟𝑒 =
(Simplified) example:
0
Attributes Value Score Weight Weighted score
Type of part (Metals, Plastics, etc.) M - - Fulfilled
Part size (dm³) 0,5 - - Fulfilled
Supply options (#) 2 0,32 43,5% 0,1392
Supply risk (%) 15 0,105 32,5% 0,034125
Remaining usage period (month) 5 0,11 7,5% 0,0825
Manufacturing/order costs (10.000 x Euro) 48 0,175 16,5% 0,028875
Item score = 0,2847
Technological
constraints
n.knofius@utwente.nl
Spare part
attributes
Weighted
average

26.  35.933 spare parts considered
Result:
 Already 1.141 technological feasible and
positive business cases identified
Example fitting-stud:
 Resupply lead time reduced by about 40%
 Manufacturing costs reduced by about 70%
10/6/16 26
APPLICATION AT FOKKER SERVICES
n.knofius@utwente.nl
Safety-belt with fitting-Stud
1) Safety stock costs (18%) 4) Supply risk (13%) 7) Supply options (10%)
2) Manufacturing/order costs (17%) 5) Remaining usage period (13%) 8) Part size
3) Demand rate (16%) 6) Resupply lead time (13%) 9) Material type

27.  11.944 spare parts considered
Preliminary result:
 15% of 175 best scoring parts are assessed
as technological feasible and economical promising
Discussion point:
 Focus on depot level maintenance or operational level
maintenance?
10/6/16 27
APPLICATION AT ARMY
n.knofius@utwente.nl
1) Demand rate (35%) 4) Resupply lead time (11%) 7) Safety stock costs (2%)
2) Supply risk (35%) 5) Manufacturing/order costs (2%) 8) Material type
3) Remaining usage period (11%) 6) Design ownership (2%) 9) Part size

28. THANK YOU!
Nils Knofius
n.knofius@utwente.nl