Pull systems design and control

Question 1

Advantages with significant item numbers?

Answer 1

• Carry more information
• Easier to identify an item
• Easier to communicate between people

Question 2

Disadvantages with significant item numbers?

Answer 2

Are longer than non-significant
Often require alfa-numeric characters
Complicates the item numbering process
Risk that the system not will cover all options
Numbers sometimes used in several companies

Question 3

What kind of engineering changes occur?

Answer 3

Those that needs to be done right away

those which can be planned in advance

Question 4

What’s a work centre?

Answer 4

manufacturing unit which is from a planning view seen as a undividable.
May have several operators and machines

Question 5

What work centre data do we have?

Answer 5

Mainly focus on capacity

• Number of machines or production units
• Number of shifts per day
• Number of hours per shift
• Expected degree of utilisation

Question 6

How can we describe degree of pull?

Answer 6

The degree of pull is the extent to which a supplying unit, authorised by a consuming unit, can deliver a quantity that corresponds to the quantity needed and can deliver it immediately

Question 7

Definition of pull system?

Answer 7

‒ Production plans are used, but not for scheduling but for capacity planning
‒ Small batch sizes
‒ No dispatch lists
‒ The start of an operation is initiated by a signal from the following operation

Question 8

Formula for number of kanbans?

Answer 8

Y = L*D(α+1)/q
Y = Number of kanbans (cards)
D = Demand per time unit
L = Lead time
q = Number of parts in each box
α = Safety factor
boxes = same +1

Question 9

Differenc between one card and two card kanban

Answer 9

One card kanban is mainly for replenishing, when a card/signal is sent the reciever will supply the sender. (move kanban)

Two card Kanban has transport cards and production cards, one is just for the replennishing and the second one is for starting production in the predecessor(move kanbans and production kanbans.

Question 10

What’s CONWIP?

Answer 10

Constant WIP
Signal sent from end what should be produced.
Signal based on dispatch list.

Question 11

Benefits of CONWIP?

Answer 11

can handle more complex environments than kanban

Allows for mix variations over time