7 - manufacturing resource planning dr. ron tibben-lembke pp. 222-234, 236-7, 240

7 - Manufacturing Resource Planning

Dr. Ron Tibben-Lembke

pp. 222-234, 236-7, 240

How do we account for LT?

System for organizing WIP releases Consider LT for each item Look at BOM to see what parts needed Release so they will arrive just as needed

Example Figure 7.2 Order quantity is 50 units LT is one week I’ve added “Net requirements” and “scheduled

releases” rows to Figure for clarity

Fig 7.2

1 2 3 4 5

Gross Requirements 10 40 10

Scheduled receipts (begin) 50

Projected Available Balance (ending) 4

54

44

44

4

Net Requirements 6

Planned Order Receipts

Planned Order Releases

6 units short

Fig 7.2

1 2 3 4 5

Gross Requirements 10 40 10

Scheduled receipts (begin) 50

Projected Available Balance (ending) 4

54

44

44

4

Net Requirements 6

Planned Order Receipts 50

Planned Order Releases 50

Order 50 units week earlier

Fig 7.2

1 2 3 4 5

Gross Requirements 10 40 10

Scheduled receipts (begin) 50

Projected Available Balance (ending) 4

54

44

44

4

44

Net Requirements 6

Planned Order Receipts 50

Planned Order Releases 50

Ending inventory

Terminology

Projected Available balance Not on-hand (that may be greater) Tells how many will be available (in ATP sense)

Planned order releases ≠ scheduled receipts Only when material has been committed to their

production Move to scheduled receipts as late as possible Preserves flexibility

Figure 7.3 1605 Snow Shovel

1605 Snow Shovel

048Scoop-shaftconnector

13122 Top Handle Assy314 scoop assembly

118 Shaft (wood)

062 Nail (4)

14127 Rivet (4)

314 scoop assembly

314 scoop assembly

14127 Rivet (6)019 Blade (steel)

2142 Scoop (aluminum)

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

BOM Explosion

Process of translating net requirements into components part requirementsTake into account existing inventoriesConsider also scheduled receipts

BOM Explosion Example

Need to make 100 shovelsWe are responsible for handle

assemblies.

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

Net Requirements

Sch Gross NetPart Description Inv Rec Req ReqTop handle assy 25 -- 100 75

Top handle 22 25Nail (2 required) 4 50Bracket Assy 27 --

Top bracket 15 --Top coupling 39 15

Figure 7.5

Sch Gross NetPart Description Inv Rec Req ReqTop handle assy 25 -- 100 75

Top handle 22 25 75 28Nail (2 required) 4 50 150 96Bracket Assy 27 -- 75 48

Top bracket 15 --Top coupling 39 15

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

Figure 7.5

Sch Gross NetPart Description Inv Rec Req ReqTop handle assy 25 -- 100 75

Top handle 22 25 75 28Nail (2 required) 4 50 150 96Bracket Assy 27 -- 75 48

Top bracket 15 -- 48 33Top coupling 39 15 48 --

Timing of Production

This tells us how many of each we needDoesn’t tell when to startStart as soon as possible?Dependent events (oh no, not that!)

(We ignore statistical fluctuations)Front schedule Cutting approach (Fig. 7.6)

p. 231Back schedule Fig. 7.7 p.232

Fig 7.8 – 13122 Top Handle Assy

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

Net Req 5

Pl Order Rec 5

Pl Order Rel 5

p. 233

Fig 7.8 – 13122 Top Handle Assy -2

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

457 Top Handle

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts 25

Proj. Avail Bal (ending)

22

22

Net Req

Pl Order Rec

Pl Order Rel

One handle forEach assembly

457 Top Handle

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts 25

Proj. Avail Bal (ending)

22

22

17

Net Req

Pl Order Rec

Pl Order Rel

457 Top Handle

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts 25

Proj. Avail Bal (ending)

22

22

17

42

22

17

17

Net Req 18 10

Pl Order Rec 18 10

Pl Order Rel 18 10

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

X

082 Nail (2 required)

LT = 1 Lot Size = 50

1

2

3

4

5

6

7

8

9

10

Gross Req 10 40 10 70 20

Sch receipts 50

Proj. Avail Bal (ending)

4

54

Net Req

Pl Order Rec

Pl Order Rel

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

Two nails forEach assembly

082 Nail (2 required)

LT = 1 Lot Size = 50

1

2

3

4

5

6

7

8

9

10

Gross Req 10 40 10 70 20

Sch receipts 50

Proj. Avail Bal (ending)

4

54

44

44

4

Net Req 6

Pl Order Rec 50

Pl Order Rel 50

082 Nail (2 required)

LT = 1 Lot Size = 50

1

2

3

4

5

6

7

8

9

10

Gross Req 10 40 10 70 20

Sch receipts 50

Proj. Avail Bal (ending)

4

54

44

44

4

44

Net Req 6 26 20

Pl Order Rec 50

Pl Order Rel 50

082 Nail (2 required)

LT = 1 Lot Size = 50

1

2

3

4

5

6

7

8

9

10

Gross Req 10 40 10 70 20

Sch receipts 50

Proj. Avail Bal (ending)

4

54

44

44

4

44

44

24

4

4

4

Net Req 6 26

Pl Order Rec 50 50

Pl Order Rel 50

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

XX

11495 Bracket Assembly

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req

Sch receipts

Proj. Avail Bal (ending)

27

Net Req

Pl Order Rec

Pl Order Rel

One bracket forEach assembly

11495 Bracket Assembly

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5

Sch receipts

Proj. Avail Bal (ending)

27

Net Req

Pl Order Rec

Pl Order Rel

One bracket forEach assembly

11495 Bracket Assembly

13122 Top handle LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 20 10 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

25

25

5

5

0

0

0

0

0

0

0

Net Req 5 20 5 35 10

Pl Order Rec 5 20 5 35 10

Pl Order Rel 5 20 5 35 10

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

27

Net Req

Pl Order Rec

Pl Order Rel

One bracket forEach assembly

11495 Bracket Assembly

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

27

22

22

2

Net Req 3 35 10

Pl Order Rec 3 35 10

Pl Order Rel 3 35 10

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

XXX

129 Top Bracket

LT = 1

1

2

3

4

5

6

7

8

9

10

Gross Req 3 35 10

Sch receipts

Proj. Avail Bal (ending)

15

Net Req

Pl Order Rec

Pl Order Rel

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

27

22

22

2

Net Req 3 35 10

Pl Order Rec 3 35 10

Pl Order Rel 3 35 10

129 Top handle bracket

LT = 1

1

2

3

4

5

6

7

8

9

10

Gross Req 3 35 10

Sch receipts

Proj. Avail Bal (ending)

15

15

15

12

12

Net Req 23 10

Pl Order Rec 23 10

Pl Order Rel 23 10

13122 Top Handle Assembly

1118Top handle

Coupling (steel)

11495 WeldedTop handle bracket

Assembly

13122 Top Handle Assembly

457 Top handle(wood)

129 Top HandleBracket (steel)

082 Nail (2)

X

XXX

X

1118 Top handle coupling

LT = 3 Safety Stock = 20

1

2

3

4

5

6

7

8

9

10

Gross Req 3 35 10

Sch receipts

Proj. Avail Bal (ending)

39

Net Req

Pl Order Rec

Pl Order Rel

LT = 2

1

2

3

4

5

6

7

8

9

10

Gross Req 5 20 5 35 10

Sch receipts

Proj. Avail Bal (ending)

27

22

22

2

Net Req 3 35 10

Pl Order Rec 3 35 10

Pl Order Rel 3 35 10

1118 Top handle coupling

LT = 3 Safety Stock = 20

1

2

3

4

5

6

7

8

9

10

Gross Req 3 35 10

Sch receipts 15

Proj. Avail Bal (ending)

39

39

54

51

51

16

Net Req 4

Pl Order Rec 4

Pl Order Rel 4

1118 Top handle coupling

LT = 3 Safety Stock = 20

1

2

3

4

5

6

7

8

9

10

Gross Req 3 35 10

Sch receipts 15

Proj. Avail Bal (ending)

39

39

54

51

51

20

20

20

20

20

20

Net Req 4 10

Pl Order Rec 4 10

Pl Order Rel 4 10

Other considerations

Safety stock if uncertainty in demand or supply quantity Don’t let available go down to 0

Safety LT if uncertainty in arrival time of supplyPlace order earlier than necessary

Order quantitiesEOQ, Lot-For-Lot, Periodic Order quantity,

more to come in ch. 14

Homework

DQ: 3, 7Problems: 3,5,6,7