Chinese-English Bilingual Teaching For Logistics

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Chinese-English Bilingual Teaching For Logistics
Supply Chain Management
Chapter 7. Stock Control ? ? ? jzj_at_sdjzu.edu.cn
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Ch.7 Stock Control

• Stock Classification ?????
• Stock Identification ????
• Forecast ????

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• Stock control is the determination and regulation
  of which items are kept in stock and what
  quantities of each are stocked without stock
  excess or stock deficiencies.
• The aim.
• a high level of stock.
• stockholding costs.

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• The range and depth of stockholdings is
  determined by an assessment of the following
  factors.
• The nature of demand
• Degree of protection against stock-outs
• Purchasing costs
• Holding costs
• Lead-time

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1. Stock classification

• 80/20 in such cases 80 of the items in stock
  typically make up only 20 of the total stock
  value, while the remaining 20 of (high-value)
  items account for 80 of the total stock value.
• ??????????????????????????,????????????????

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1. Stock classification

• ABC groups
• Category A items 10 of items by volume account
  for 70 of value
• Category B items 20 of volume accounts for 20
  of value
• Category C items 70 of volume accounts for 10
  by values.

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1. Stock classification

• The stock control policy for the categories
  might be as follows
• Class A close control and checked once a month
  
• Class B medium control and checked every three
  months
• Class C minimum control with free issue

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2. Stock identification

• Stock consists of many different types of
  individual items.
• The easiest way to identify an item is by name or
  word description.
• The problem is that different people may describe
  the same item using different words.
• This can result in duplication of the same item
  with consequent higher than necessary
  stockholding levels

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2. Stock identification

• The development of a coding system follows a
  series of stages.
• Identification of each item by function and need.
• Specification of each item.
• Classification into groups and sub-groups.
• Application of code.

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2. Stock identification

• Classification into groups and sub-groups could
  be made on any of the following bases.
• Nature of material
• End use of material
• Location on stores
• Source of supply
• End user customer

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2. Stock identification

• ??????????
• ??,??????100???????????
• OPITZ??(?)?MNTPO?AHOB(???)?BRISCH??(?)?KK-3??(?)?C
  ODE??(?)?MICLASS??(?)??
• OPITZ??

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2. Stock identification

• In the Brisch system there are 2 parts to the
  code. The surname comes first and provides the
  broad item classification.
• Surname
• 1st figure main classification ????
• 2nd figure sub-group ?? of main classification
• 3rd figure item classification ????

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2. Stock identification

• The forename which follows describes each item
  in detail e.g.
• Forename
• 4th figure length
• 5th figure diameter
• 6th figure type of head
• 7th figure surface finish

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2. Stock identification

• So 100- 5648 could mean
• 1 bought out parts, 0 fasteners and
  fixings?????, 0 nuts and bolts ????
• 5 2cm, 6 10mm, 4 hex RD hex (??,radial
  direction ??), 8 zinc coated

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2. Stock identification

• The coding details of all stock items are
  normally maintained in a list or catalogue called
  the stores vocabulary.
• This facilitates stock rationalization, whereby
  stock codes can be analyzed and any duplicate
  stock can be easily highlighted.
• As well as codifying items into unique part
  numbers, inventory can also be broken down into
  generic constituent areas.

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2. Stock identification

• Categorization of stock may also be used for
  accounting or analytical reasons.
• Maintenance stock
• Project stock
• Insurance stock
• Strategic stock

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3. Forecast

• An effective stock control system involves
  decisions on
• how much stock to hold using forecasts of usage
  and replenishment
• how much to orderorder quantity
• when to order for stocktiming of orders.

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3. Forecast

• Each item stocked, decisions on how much should
  be held are made on the basis of demand
  forecasting.
• Forecast comparisons use sales data and
  production data from the bill of materials.
• ??MRP?????,???????????????????????????????????????
  ???????

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3. Forecast --- (1) EOQ

• ?????? EOQ
• annual usage (??????/???)
• acquisition cost per order (??????)
• stockholding cost per unit (????????/???/????????)

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3. Forecast ????--- (1) EOQ

• EOQ example
• ??????EOQ
• So order quantity is 37.

Annual usage 400
Acquisition cost 50 per order
Price 150
Holding cost 20 of price
37 units
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3. Forecast ---(2) safety stock

• This is the lead-time(???) which includes
  things like
• time to identify then authorize replenishment
• time to establish supplier contact and complete
  paperwork
• time for the supplier to obtain or produce the
  goods
• time to have the goods delivered
• time for goods inwards/receiving and quality
  checking time.

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3. Forecast ---(2) safety stock

• Safety stock (or buffer stock)
• A fixed quantity
• A given days worth
• A quantity calculated statistically based on
  usage and supply factors

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3. Forecast ---(3) ROL

• Re-order levels are used to trigger consideration
  of stock reordering action.
• It is a stock level at which new stock must be
  ordered if replenishment is to arrive before a
  stockout occurs, provided demand remains as
  predicted.

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Understanding Inventory

• The inventory policy is affected by
• Demand Characteristics
• Lead Time
• Number of Products
• Objectives
• Promote service level
• Minimize costs
• Cost Structure

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Cost Structure

• Order costs (acquisition/administration costs )
• Fixed
• Variable
• Holding Costs (stockholding costs )
• Insurance
• Maintenance and Handling
• Taxes
• Opportunity Costs
• Obsolescence

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EOQ A View of Inventory
Note No Stockouts Order when no inventory
Order Size determines policy
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EOQ Calculating Total Cost

• Purchase Cost Constant
• Holding Cost (Avg. Inven) (Holding Cost)
• Ordering (Setup Cost)Number of Orders Order
  Cost
• Goal Find the Order Quantity that Minimizes
  These Costs

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EOQTotal Cost
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EOQ Optimal Order Quantity

• Optimal Quantity (2DemandSetup
  Cost)/holding cost
• Setup Cost ??/(??)????

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??????(EOQ)??

• ??????(Economic Order Quantity,EOQ)??????
• ???????
• ????????
• ??????????
• ?????????? ...
• ??????(EOQ)?????
• ????????????,?????????????????????????????????????
  ?????

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EQQ(????? Stationary)

• ????/???(Economic order quantity,EQQ)????????????
  ????????????????????????????
• ????
• ??????????,
• ???????,
• ????????

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EQQ(????? Stationary)

• ????

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EQQ(????? Stationary)
?????????????16000?,????????2?,???????40?,??????
?Q?
Q
800?
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Q A !
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Exercises

• ?? P94