Group No. 5

1

Donner Company Case write up for OM course

Group Number 5

Members:

KEK Sashank : 1511393

Pooja Gupta : 1511444

Sangbarta Chakraborty : 1511431

Sandip Datta : 1511430

Sanket Kale : 1511398

a) Information flows within Donner factory: The schematic for information flows within the Donner factory is shown in Exhibit 1. Plummer

and Altmeyer give an estimate of the time required and cost to complete the order to the

customer. If the customer accepts the bid, Altmeyer gives the material specifications to

procurement manager who procures all the raw materials to complete the order. Factory

order is prepared which reaches Flaherty who schedules all the operating processes so as to

complete the order within the estimated time. The information flow in the exhibit shows a

sample order as it flows through the assembly line covering all the standard processes.

b) Capacity analysis:

i. Use of alternative technologies: Donner company has seven manual drills and one CNC drill for drilling operation. As can be

seen from Exhibit 2 of the case, the setup time required for CNC drill is 16 times that of setup

time required for manual drill. But the run time of CNC drill is 16 times lesser than manual

drills. Hence for orders of large size, CNC drilling would consume lesser time than manual

drills.

As with the profile punches, the setup time for CNC router is 3 times that of manual punch

press while the time required per board by CNC is only half of what is taken by manual punch

press. Hence for profile punching the order size has to be considerably large enough to get

the advantage from CNC punch press.

The following calculations find the minimum order size above which CNC drill CNC router

would take less time than manual machines to complete the processes.

Let x be the number of boards ordered.

Comparing 1 Manual drill time = 1 CNC drill time for x boards

15+0.080*500*x=240+0.004*500*x => x = 5.92

Hence for orders of size >5 CNC drill is the suitable option.

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There are 7 Manual drills and one CNC drill. If we consider the case each board is fed into each

manual drill simultaneously the equation gets modified to

15+0.080*500*x/7=240+0.004*500*x => x = 60.58 [7 simultaneous manual drill usage]

Hence for orders of size >60 CNC drill seems the suitable option but it is highly unlikely to get

n number of manual drills free for 1 order as there will be almost continuous simultaneous

stream of orders being made and worked upon.

Similarly Punch press and CNC router has a trade-off in setup time and run time.

Let x be the number of boards ordered.

Comparing 1 Punch Press time = 1 CNC router time for x boards.

50+1*x=150+0.5*x => x = 200

Hence for orders of size >200 CNC router is the suitable option.

ii. Standard Labour Time As we clearly proved in the last part that for an order of one board we would be only using

one manual drill. And we have also proved that in case of using one drill for one order, CNC

drill can be used for orders of quantity greater than 6 boards. But in the case of using seven

drills for one order, CNC drill should be used for orders greater than 61 boards.

In this question, we have to find the standard labour time for an order of 1 board, 8 boards

and 200 boards. In case of 1 board it is clear that only 1 drill can be used. In case of 8 boards,

we have two options of either using 1 drill or 7 drills in manual method. If only 1 drill is used,

the condition from previous part says for order greater than 6 boards, CNC drill is more

preferable. The option of using 7 drills for an order of 8 boards is discarded because it doesn’t

make economic sense to separate individual boards and use different drills for boards from

the same panel. Calculations show that using CNC drill would save the standard labour time

by a great extent. For an order of 200 boards, it is clear that only CNC drill has to be used.

All the calculations are explained in the table attached in the Appendix. Calculations show

that the standard labour times for the given orders are as follows:

Order size Drill method chosen Standard Labor Time (in minutes)

1 Manual 396.55

8 Manual (CNC) 654.05

200 CNC drill 1840.25

In the case of profile punching we saw that the order size has to be more than 200 for CNC

router to take less time than manual punching press. For order sizes of 1 and 8 boards, manual

profile punching takes less time. For order size of 200, both CNC router and profile punching

take the same time and hence the decision depends on the availability of the resource in case

of profile punching.

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As can be observed from the exhibit, the drilling process is the bottleneck process irrespective

of the batch size and also irrespective of the decision to use manual drilling presses of CNC

presses. Hence it becomes necessary for Donner, to schedule in such a way that the drilling

processes, both manual and CNC are never starved.

c) Problem identification and resolution: Following are the problems identified by Donner company as have been discussed in the

case:

1. Changing nature of orders: Order sizes ranged from 1 circuit board per order to more

than 1000 circuit boards per order. Also, every order required different processes and

different materials as specified by the customer.

2. Rush orders: On an average Donner received three rush orders in a week which had

to be delivered within four days adding to the pressure of already congested assembly

line.

3. Productivity: A large number of orders required rework because the products failed

the inspection process.

4. Quality: About 9 in every 10 returned orders were because Donner had missed

performing one or two operations. These returned boards had to be worked upon

again and delivered again within one or two days.

5. On time delivery: The company had to quote three weeks for orders less than 1000

boards and four weeks for more than 1000 boards owing to competition. The

deliveries had been late by almost 9 days on an average in the recent months.

On the basis of problems identified, Donner Company can implement various actions to

improve their productivity, quality performance and on time delivery promise.

1. Breaking of large orders into smaller sizes: The size of orders varies from as low as

only 1 circuit board per order to more than 1000 circuit boards per order. Hence if a

smaller order is stuck behind a larger order, it takes a lot of time for the larger order

to finish before starting the work on the next order. If the larger orders are split into

smaller sizes, the subsequent smaller orders can be put in between them to ensure

delivery of smaller orders on time. This would also reduce the need to expedite the

orders by a large amount.

2. Have a different line dedicated for rush orders: Donner receives about three rush

orders every week. Hence Donner can have a dedicated assembly line to complete

rush orders and also deliver on time. This line will mostly be occupied owing to large

number of rush orders but the workers can be given the work of normal orders

whenever there are no rush orders since the skills required are not very different.

3. Prepare a checklist of processes: Every 9 in 10 orders returned by the customers are

because Donner missed one or two processes during production. Hence, Altmeyer,

the design engineer, when producing the factory order can also produce a checklist

of operations to be performed to complete the given lot. This checklist will be

attached to the rack which carries the boards of that order and the workers will tick

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the checklist option after completing that process. This would ensure all the activities

are completed in sequence and no activity is missed out when completing the order.

4. Use of ICT for quicker procurement: Donner needs to make contracts with the

suppliers to ensure cheaper procurement costs. The suppliers should be developed

to meet the requirements of Donner. Use of ERP systems like SAP with suppliers can

help suppliers track real time what orders are received by Donner and immediately

send the required material to Donner. This can reduce the procurement time required

from 4 days to about 1 or 2 days even for normal orders.

5. Apart from that, proper training of workers to develop their skills since most of the

jobs require a lot of judgement and proper layout of factory to reduce walk times of

workers must be done to improve productivity.

6. The programming of CNC drilling which takes 240 minutes of setup time is currently

done when the order reaches the CNC workstation. Instead Altmeyer can create a

programme required for that order and save it into the CNC machine beforehand. The

programme can be retrieved when the batch reaches the CNC station. The added

advantage of this is also that if Donner gets two orders with similar drilling

requirements, the saved programme can suffice both the orders thus saving the setup

time.

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Exhibit 1

Information flow in the process

Preparing

Customer

Bid

(Plummer

&

Altmeyer)

Scheduling

of the

order

Artwork

Generation

Punch

Tooling

Holes

Metallizati

on

Inspect and

Shear

Panel

Preparation

Laminate

and Expose Develop Electroplate Strip DFPR

Soldermask Punch

Press

Customer

Response

Factory

Order

(Altmeyer

for normal

Schnabs for

rush)

Procureme

nt (1-2

days, same

day for

rush order)

Manual

or CNC?

Manual

Drilling

CNC

Drilling

Yes

Etch and

tin strip

Solder Dip

Punch

Press or

CNC?

CNS Router

Inspect,

Test and

Pack

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Exhibit 2: Calculation of standard labour time for 1 board, 8 boards and 200 boards

Standard Production Times 1 Board 8 boards 200 boards

Operation

Setup Time (min)

Run Time (min)

Run Time/ Board

Time taken (Manual)

Time taken (CNC)

Time Taken (CNC)

PREPARATION

Artwork Generation 29 0 0 29 29 29

Inspect & Shear 20 0.5/panel 0.5 20.5 20.5 32.5

Punch Tooling Holes 10 0.5/panel 0.5 10.5 10.5 22.5

IMAGE TRANSFER

Drill

Drill (Manual) 15 0.08/hole 40 55

CNC Drill 240 0.004/hole 2 256 640

Metallization 10 0.75/panel 0.75 10.75 10.75 28.75

Dry Film Photoresist

Panel Prep 5 0.2/panel 0.2 5.2 5.2 10

Laminate & Expose 20 2/panel 2 22 22 70

Develop 20 0.2/panel 0.2 20.2 20.2 25

Electroplate 25 8.5/panel 8.5 33.5 33.5 237.5

Strip DFPR 5 0.2/panel 0.2 5.2 5.2 10

Etch & Tin Strip 10 0.2/panel 0.2 10.2 10.2 15

FABRICATION

Soldermask 45 1.5/panel 1.5 46.5 46.5 82.5

Solder Dip 30 0.5/panel 0.5 30.5 30.5 42.5

Profile

Punch Press (Manual) 50 1/board 1 51

CNC Router 150 0.5/board 0.5 154 250

Inspect, Test, Pack 45 1.5/board 1.5 46.5 345

Total Time (min) 396.55 654.05 1840.25

Total Time (hours) 6.60916667 10.9008333 30.6708333