Logo  
Home    Gray Research    Consulting  Workshops    Books    Articles    Affiliates    Software

 

MRP II Standard System: 

Detailed Checklist

From: 

The MRP II Standard System Workbook

Copyright:  Landvater and Gray

Call Chris Gray at 603 778-9211 for help in evaluating your software against these functions.  

 SERVICES

S&OP Resources

Books

On-site S&OP Education

S&OP Instructor's Manual

S&OP Software

S&OP Consulting

 

Education Courses
On-site Workshops/Classes

 

Education Materials

S&OP Instructor's Manual
MPS Instructor's Manual

 

Consulting and Research
Consulting
Class A Certification
Performance Assessment
Software Evaluation and Selection

MRP II Standard System Definition
Software Supplier Directory (140K)

 

Software
eSOP - S&OP Software

 

Books

Recommended Books
The Right Choice
by Chris Gray

The MRP II Standard System by Chris Gray and Darryl Landvater

Sales and Operations Planning Handbook by Don Rice and John Civerolo

 

ARTICLES

Master It (Master Scheduling and Lean Production)

 

Staying in Business with e-Business

 

Time to Get Serious About e-Commerce

 

Does Your Supply Chain Measure Up? 

 

The Party's Over - The Real Aftermath of Y2K 

 

Back to Basics

 

Software and Simplicity

 

Turning Education Expense into an Investment that Pays Off!

 

ERP Software: Valuable Tips for Selection and Implementation

 

Coca-Cola: "Always" Class A 

When The MPS Is MIA ...

Can Lean And Software Co-exist?  

Sales and Operations Planning and Lean Manufacturing

On Education and Training

 

 

AFFILIATES

 

Associates and Related Companies
Worldwide Excellence Partners
Partners for Excellence
Graham Barton (New Zealand)

Bill Belt Excellence (French language)


Who We Are
Chris Gray Biography
Books by Chris Gray

 

Basic Architecture

The logic of MRP

  1. Regenerative
  2. Batch net change
  3. Continuous net change
  4. Bucketed (number of buckets)
  5. Bucket less
  6. Planning horizon
  7. Shop calendar with user specified holidays, non-working days, etc.

Master Scheduling Logic

  1. Regenerative
  2. Batch net change
  3. Continuous net change
  4. Bucketed (number of buckets)
  5. Bucket less
  6. Planning horizon
  7. Shop calendar with user specified holidays, non-working days, etc.

Capacity Requirements Planning Logic

  1. Regenerative
  2. Batch net change
  3. Continuous net change
  4. Bucketed (number of buckets)
  5. Bucketless
  6. Planning horizon
  7. Shop calendar with user specified holidays, non-working days, etc.

Sales and Operations Planning

A way to define product families for S&OP

Provide basic information and the transactions to maintain it for each product family:

    Sales and shipments data, including: 

  1. Planned bookings ( or demand in pure make-to-stock situations).
  2. Actual bookings (demand)
  3. Actual customer orders by ship date
  4. Actual shipments

    Production Data

  1. Planned production
  2. Actual production

    Performance Data

  1. Planned backlog for prior periods
  2. Actual backlog for prior periods
  3. Planned inventory for prior periods
  4. Actual inventory for prior periods

The ability to state future S&OP plans directly by product family

A S&OP report that includes the following information:

    Historical

  1. Planned and actual bookings (or demand)
  2. Actual customer orders by promised ship date
  3. Planned and actual production
  4. Planned and actual inventory (make-to-stock)
  5. Planned and actual backlog (make-to-order)

    Current and Future

  1. Planned bookings and scheduled shipments
  2. Planned production rates
  3. Planned inventory
  4. Planned backlog

Comparison of sales, production and inventory or backlog plans to actual sales, production, and inventory or backlog.

A S&OP reporting horizon that extends beyond the master scheduling horizon.

A method to convert the S&OP from the primary unit of measure to units of measure meaningful to finance, manufacturing, engineering, sales and marketing, etc.

A method to convert marketing families into manufacturing families, or vice versa.

A method to compare and evaluate the S&OP against the business plan.

A mechanism to shift S&OP data to different buckets as the calendar rolls (i.e., earliest past due period is dropped, and the next oldest period is shifted to the oldest period).

A way to define key resources and representative routings that relate the individual master schedule items to the key resources required to produce them. The representative routings should contain the resource identifier, number of hours, pounds, molds, etc. and the approximate offset from the completions of the master production schedule order.

A summary rough-cut capacity planning report displaying the total capacity required for each period and the capacity available in the period. The rough-cut capacity report would normally have the same format as the detailed capacity planning report.

A detailed rough-cut capacity planning display showing the individual master schedule orders (and spare parts demands) causing the rough-cut capacity requirements in each time period.


Master Production Scheduling

A master schedule order that is a statement of production and which is not changed in any way by the computer (functionally equivalent to a firm planned order).

Ability to master schedule at any level in the bill of material.

Ability to reduce the work load on the master scheduler by creating suggested master schedule orders. This can be done in either of two ways:

  1. Creating planned orders that are not passed on to MRP to explode.
  2. Creating planned orders beyond the master schedule planning horizon only, and allowing these orders to be exploded into MRP.

Specialized transactions to reduce the time required to create and maintain the MPS. A rate generator is helpful in a high volume or mixed model master scheduling environment.

A master Schedule report or reports with the following information:

  1. Descriptive (fields affecting master schedule computations)
  2. Time phased data:

Demands

  1. Sales forecast
  2. Production forecast
  3. Customer orders
  4. Branch warehouse demands
  5. Inter-plant orders
  6. Dependent demands

Production (Master Production Schedule)

  1. Scheduled receipts
  2. Master Schedule orders

Calculations

  1. Projected available balance
  2. Available to promise
  3. Suggested master schedule orders
  1. Pegging
  2. Details to schedule receipts and master schedule orders
  3. Exception messages

A reporting horizon for the MPS that covers a period greater than the cumulative lead time for the item.

The MPS (scheduled receipts and master scheduled orders) shown by due date, not need date. If scheduled receipts are separated from the master schedule orders, then scheduled receipts are shown by due date, while the master schedule orders can be shown by due date or release date.

A projected available balance calculation that shows the projected on-hand balance, netting demands against the on-hand balance and scheduled receipts and master schedule orders. Scheduled receipts and master schedule orders are added in the periods where they are currently due.

An available-to-promise calculation that shows where new customer orders can be promised on existing customer orders and the existing MPS. The ATP calculation can be done in either of two ways:

  1. Once for each master schedule order
  2. Accumulated, showing the total ATP up to a point in the planning horizon.

Logic to summarize the master schedule by product family for comparison to the production plan. This has two parts:

  1. Logic to summarize family grouping
  2. Logic to summarize master scheduling periods (normally days or weeks) into SOP periods (normally fiscal periods).

Logic to summarize the master schedule by subfamily (for example, the different types of engine modules that are a part of a family of automobiles).

Logic to generate the following exception messages:

  1. Reschedule a scheduled receipt or master schedule order to an earlier date.
  2. Reschedule a scheduled receipt or master schedule order to a later date.
  3. Not enough in the MPS to cover demand
  4. Master schedule order due for release
  5. Over promised customer orders
  6. Past due schedule receipt or master schedule order.

The ability to define a planning bill of material where the parent item is a type of product and the component item numbers are (typically) modules or options. For master scheduling and order entry purposes, the planning bill of material must identify which options are part of which option grouping, which are required and which optional, how many of an option must be ordered if the option appears on a customer order, and the percentage popularity of an option.

The ability to master schedule both levels of a planning bill of material.

The ability to distinguish pseudo from build-able options in a planning bill of material.

The ability to compute production forecasts for the options based on the unsold quantities in the master schedule for the type of product. One way to do this would be by exploding the ATP.

Logic to handle low volume (for the type of product) and small percentages (for the product) problems in two level master scheduling.

Logic to eliminate rounding problems in low/small percentage situations.

The ability to handle changes to planning bills of material including:

  1. Effectivity dates
  2. Changes tied to a specific master schedule order

A way to define key resources and representative routings that relate to individual master schedule items to the key resources required to produce them. The representative routings should contain the resource identifier, number of hours, pounds, molds, etc. and the approximate offset from the completion of the MPS order.

Logic to accumulate information from the detailed routings at all component levels to make a first cut at a representative routing.

A calculation that extends the representative routings by the MPS to generate rough-cut capacity requirements.

When necessary, the ability to include spare parts demands in the rough-cut capacity calculations.

A summary rough-cut capacity planning report displaying total capacity required for each period and the capacity available in the period. The rough-cut capacity planning report would normally have the same format as the detailed capacity planning report.

A detailed rough-cut capacity planning display showing the individual master schedule orders (and spare parts demands) causing the rough-cut capacity requirements in each time period.

A lead time picture that accumulates and displays the lead time down through the product structure.

A calculation of cumulative lead time for each item.


Demand Management

Simple forecasting techniques and a method for evaluating them. These might include simple strategies like a moving average, or "Whatever was sold the last three months is what will be sold in the next three months," or something more complex like exponential smoothing. For some companies it may be important to include models of product life cycle for assistance in forecasting.

A way to take seasonal factors into account in the forecast. The seasonal factors may be entered manually or developed based on history and reviewed and approved by a person responsible for forecasting.

A way to break down and allocate forecasts of families of items by warehouse, configuration, package size, etc.

A way to review and approve (or override) the forecast before updating the system. This would normally take the form of a forecast report or display so that the forecasting techniques can be combined with good human judgement.

An order entry system with transactions to add, delete, and change customer orders. Customer orders are handled as demand in MRP or MPS.

A way to have multiple line items on a single customer order. The multiple line items may be for different items on the same date, for different items on different dates, or the same item on different dates. One or more shipments may be included on a single customer order.

At least five pieces of information stored for each customer order line item:

  1. Item number
  2. Required (promised) date
  3. Quantity
  4. Customer order number
  5. Customer request date

Paperwork to assist the order entry, stockroom or finished goods inventory people:

  1. Hardcopy customer confirmations
  2. Picking lists
  3. Shipping documents

A method for promising customer orders based on the ATP, not "standard lead time".

An available-to-promise check for each item on the customer order that is part of the order entry/promising process. There are a number of different ways to do an ATP check:

  1. In cases where the customer promise is made before the order is entered, the ATP has to be checked prior to the actual entry.

    Done using the MPS report or display

    Done using special on-line promising displays to automate the checking and promising process.

  2. The ATP checked as the order is entered, with items not available on the requested date highlighted and shown with both the requested date and the available date for review by a person.
  3. ATP check run after order is entered with orders not available on the requested date listed on a report or in an on-line display.

Additional capabilities to handle customer orders for products made-to-order from a number of options. For products made from options, the order entry mechanism should include two capabilities:

  1. Assistance in selecting the proper modules and options for each product
  2. A check of the ATP for both the type of product and each option

A method for comparing existing customer orders to the forecast for the purpose of identifying demand that may be abnormal.

A way to indicate demands that have been identified as abnormal.

Forecast consumption logic that includes the following functions:

  1. A method for handling customer orders that do not match the forecast week-by-week, but which may be a good approximation of the demand forecast over longer periods.
  2. A method for handling past due forecasts and past due customer orders.

A calculation of total demand that takes into account the consumed forecast, normal and abnormal customer orders, dependent demands, distribution requirements, and inter-plant orders.

A way to enter independent demands into the MRP system. These independent demands (forecasts and customer orders) would be added to the exploded gross requirements and the total would be used as requirements for MRP.


The Netting and Exception Checking Logic of MRP

A netting calculation that makes the rescheduling assumption.

A calculation of the beginning available balance from the available stockroom balance less safety stock. Safety stock can be specified by item.

Time phased allocations or logic that reduces the beginning available balance by the allocated quantity (if allocations are not time phased).

Netting logic for phantoms, transients, or self-consumed assemblies. Items that are phantoms need to be coded as such. If an on-hand balance exists, the system uses its to satisfy gross requirements prior to blowing through and calling for new sets of components.

A shrinkage factor and logic that uses the shrinkage factor to show the effect of shrinkage on scheduled receipts. In addition, the shrinkage factor is used to compute the correct planned order quantity. The shrinkage factor can be defined by item.

Logic to generate an exception message for orders that are needed at earlier dates.

Logic to generate an exception message for orders that are needed at later dates.

Logic to generate an exception message for orders that are not needed and should be canceled.

A method for maintaining accountability if orders are "automatically" rescheduled.

Logic to generate an exception message for past due scheduled receipts.

Logic to generate an exception message for planned orders due for release. This would normally be done using a release horizon of a few days to a week.

Logic in a net change MRP system to find exceptions caused by the passage of time. These exceptions would include past due scheduled receipts and planned orders due for release.

Fail-safe logic in a net change MRP system to remind a planner of any exception message that has not been resolved after a few days.

Exception checking logic to produce messages for parameter violations.


Order Planning and Explosion

The due date of a planned order calculated as the date of the unsatisfied requirement.

Safety time defined by item. Logic that uses safety time to compute planned order due dates that are earlier than the date of the unsatisfied requirement. In addition, the safety time is used in generating the recommended date in rescheduling exception messages.

An order policy specified for each item individually. The order policies include:

  1. Lot-for-lot
  2. Fixed order quantity
  3. Period order quantity
  4. Specialized ordering rules for one-time activities

A fixed order quantity or number of periods specified by item when the fixed quantity or period order quantity policies are specified.

Logic for lot-for-lot ordering that creates a planned order for the exact quantity required.

Fixed order quantity ordering that creates planned orders in either of two ways:

  1. A single planned order in multiples of the fixed order quantity
  2. Multiple planned orders each for the fixed order quantity

A period order quantity calculation that creates a planned order that covers the unsatisfied requirements for a specified number of days or weeks.

A specialized ordering rule for one-time items that creates a planned order on the earliest date the item is ever needed. This order policy would be used to handle new product engineering, FDA certification, or excavation of a construction site in situations where MRP is being used to schedule projects of this nature.

An order minimum that can be specified by item. The order minimum increases the planned order quantity up to the minimum.

An order multiple that can be specified by item. The order multiple rounds each planned order up to the next multiple.

An order maximum that can be specified by item. The order maximum works in either o two ways:

  1. As a key to exception logic that identifies orders that will exceed the maximum (recommended way).
  2. As a cut-off to the planned order quantity.

The start of a planned order computed by offsetting the due date by the lead time. Planned orders are exploded into gross requirements for component parts using the bill of material, the order quantity times the quantity per, and the start date of the order.

A product structure lead time offset that can be specified in a bill of material relationship:

The product structure lead time offset is used by both the allocation logic and the explosion logic of MRP to properly time phase components not required at the start of the parent planned order.

The product structure lead time offset must be integrated with the component availability check and allocation logic, and the pick list generation.

A scrap factor that can be specified in the bill of material relationship. The scrap factor is used by both the allocation logic and the explosion logic of MRP to reflect additional component requirements due to scrap.

Net change MRP system: a method for updating gross requirements for planned orders that have been rescheduled to an earlier or later dates.


Entry into the Planning Sequence for Processing

Regenerative MRP system: Any items with gross requirements, allocation, scheduled receipts or firm planned orders are entered into the planning sequence.

Net Change MRP system: Entry into the planning sequence based on either of the following:

  1. Transactions that have the potential to affect the material plan (for example, changes to the bill of material, unplanned inventory transactions, planned inventory transactions for more than the planned quantity or being done early, changes to scheduled receipts or firm planned orders, changes to scrap factors, lead times, order policies, etc.).
  2. Potential changes to the plan that result from planning a parent item. (For example, new planned orders were calculated for the parent item causing the gross requirements for the components to change. In this situation the components should be entered into the planning sequence.

Low level codes (or the equivalent) to sequence the netting and order planning logic properly. An item should be planned only after all of its parent items have been planned.  


Firm Planned Orders

Netting logic that recognizes firm planned orders (FPOs) and treats them as scheduled receipts. Exception messages should be generated for:

  1. FPOs needed at an earlier date
  2. FPOs needed at a late date
  3. FPOs that are candidates for cancellation
  4. FPOs due or overdue for release
  5. Past due FPOs

A method for exploding firm planned orders into component requirements. These requirements should not be treated as allocations in the system. Typical methods for generating the requirements include:

  1. Explode FPOs like other planned orders in the order explosion routines of MRP.
  2. Create component requirements at the time the firm planned order is created, maintaining these requirements as part of the maintenance transactions to change or delete FPOs.

The ability to enter a FPO for a purchased item and specify that it will be released as a manufacturing order, or vice versa. In the situation where a firm planned order is specified as a purchase order for a manufactured part, the system should bypass the order explosion logic.


Pegging

Pegging information for gross requirements that include date, quantity, and parent item number.

Pegging information for allocations that include date, quantity, and parent item number. The parent order number is helpful, would be required for allocations from customer orders.


Human Engineering

An MRP display or displays with the following information:

    Descriptive (all fields affecting the material requirements planning computations)

    Time phased data

  1. Demands (gross requirements, allocations, customer orders, forecasts, etc.)
  2. Scheduled receipts
  3. Firm planned orders
  4. Planned orders
  5. Projected on-hand balance

    Exception messages

    Pegging

    Details to the scheduled receipts and firm planned orders.

A time phased display that is a logically organized listing, in either of the normal formats:

  1. Horizontal
  2. Vertical

A reporting horizon for the MRP display that covers a period greater than the lead time for the item.

For horizontal display of the MRP information, time buckets displayed as weekly (or smaller) periods, at least through the item’s lead time.

Scheduled receipts and FPOs shown by due date, not need date. If scheduled receipts are shown on a separate line or in a separate column from the FPOs, then scheduled receipts are shown by due date while the FPOs can be shown by due date or planned start date.

A projected on-hand balance calculation that shows the projected on-hand balance, netting demands against on-hand balance and scheduled receipts, FPOs, and planned orders. Scheduled receipts, FPOs and planned orders are added into the projected on-hand balance in the periods where they are currently due.

The display of exception messages that includes the English text of a message (not uninterpreted exception codes) and additional information to assist the planner in finding the problem and resolving it. This additional information normally includes the order number, current due date and quantity, and the recommended reschedule date.

All exception messages for the same item appear together, and are grouped by planner number.

A pegging display that shows the date quantity, and parent item number for gross requirements and allocations. The parent order number is helpful for allocations and required for customer orders.

A display of details to scheduled receipts and firm planned orders that includes the order number, date and quantity remaining on order.

A way for a planner to work by exception, i.e., an exception report or display that serves as an index to the items with problems that require attention.

Displays of MRP information that are organized in logical, uncluttered block of information and presented in a standard format.

A well engineered on-line system that includes the following:

  1. Menus to assist new users in understanding the functions of the system and in moving from function to function
  2. The ability to move directly from one display to another based on the way a planner would logically work (i.e., a way to bypass the menus).
  3. The ability to carry key fields (part numbers, order numbers, etc.) From one screen to another so that this information does not have to be reentered constantly.

Assistance in seeing several pieces of information that may not be part of the same report or display, or in getting printed backup information quickly. Several solutions are possible:

  1. Split screen displays.
  2. A way to produce a printed copy of the display screens.

In a well engineered system with printed reports, no more than two printed MRP reports to show the following information for an item:

  1. Basic descriptive data that affects the calculations
  2. Time phased data
  3. Pegging
  4. Exception messages
  5. Supporting details to scheduled receipts and FPOs

MRP reports sequenced by responsibility.

Some method of reducing the volume of information printed each time MRP is run. Common methods include:

  1. Printing by exceptions (only items with exception messages) with backup information available through on-line inquiries.
  2. Printing by exception with microfiche for backup data.

A method for reducing pegging information for certain items like common hardware.


Bill of Material Subsystem

The ability to store and maintain parent-component relationships. The transaction system for maintaining bills of material would typically include:

  1. Add a bill of material relationship
  2. Change a bill of material relationship
  3. Delete a bill of material relationship

A quantity per field with enough digits to the left and the right of the decimal point (e.g. XXXXX.XXXXX) to handle the product.

An unlimited number of components in any single-level bill of material.

The ability to have a component appear several times in the same single-level bill of material.

The ability to define purchased items with bills of material.

The ability to identify the operation or operations at which an item is used in the manufacturing process.

Additional bill of material transactions:

  1. Multiple delete: delete a complete bill of material
  2. Multiple replace: replace one component with another in all usages
  3. Same-as-except: copy a bill of material and attach it to another parent item

Where-used relationships maintained as the bill of material changed.

Bill of material reports or displays that include:

  1. Single-level bill of material
  2. Multi-level bill of material
  3. Single-level where-used listing

Additional bill of material reports or displays:

  1. Multi-level where-used listing
  2. Summarized bill of material
  3. Summarized where-used listing

Logic to update the low-level code based on changes to the bill of material.

A continuity check to verify that a component is not structured to itself, directly, or indirectly. The low-level logic can provide this function.

Low-level code updating done either:

  1. On-line as changes occur
  2. In a batch run just prior to an MRP explosion, (for all items or by exception-only for those items which have been added to higher level bills of materials).

Net change MRP: A mechanism to update gross requirements when the bill of material changes. Common methods include:

  1. In the bill of material transaction system when the bills are changed
  2. Deleting all planned orders for the parent item and the associated gross requirements for the components as part of the bill of material transaction processing and recreating them in the logic of MRP.
  3. Marking items with bill of material changes in the bill of material transaction processing, with logic in MRP to match the current bill of material against the old gross requirements; adding, changing, or deleting component requirements as required.
  4. Marking items with bill of material changes in the bill of material transaction processing, with logic in MRP to delete any existing planned orders and exploded gross requirements, and then recreate them as necessary.

Engineering effective dates and effectivity logic to tie engineering changes to a specific date. For components active on the specified dates, gross requirements are generated by the order explosion logic. For components that are not active on the specified dates, the components would be bypassed and no gross requirements generated.

Bill of material deviations tied to a specific order provided in any of several ways.

  1. Serial number effectivity logic
  2. Lot number effectivity logic
  3. Attaching gross requirements to firm planned orders and providing a transaction system to add, change, and delete these requirements as needed.
  4. Other

A method for defining a disassembly bill of material, and material requirements planning logic that handles disassembly scheduling and the receipt of parts from a disassembly process.

A method for defining a byproducts or coproducts bill of material, and the proper material requirements planning logic to handle byproduct/coproduct scheduling.


Inventory Transaction Subsystem

A planned issue transaction that reduces the balance on hand and quantity allocated (both the total allocated and any individual allocations).

A planned receipt transaction for manufacturing orders that increases the balance on hand and reduces the order quantity on the scheduled receipt.

A planned receipt transaction for purchase orders that works in either of two ways:

  1. When material is moved directly to stock without inspection, the transaction increases the balance on hand and reduces the purchase order quantity.
  2. When material is moved to inspection prior to the stockroom, the transaction increases the balance in inspection and reduces the purchase order quantity (or alternately, leaves the purchase order quantity open and updates and inspection quantity that is more like a reference).

A receipt from inspection transaction that increases the on-hand balance and reduces the quantity in inspection. In the case where the inspection quantity is more of a reference field, the transaction also reduces the purchase order quantity.

Planned inventory transactions support situations where the transaction is for a quantity different from that planned. These situations include:

  1. Partial planned issues
  2. Partial planned issues where the associated allocations should not be closed out short
  3. Planned issues greater than the planned quantity
  4. Partial planned receipts
  5. Partial planned receipts where the associated allocations should not be closed out short.
  6. Planned receipts greater than the planned quantity

Transactions to handle incoming inspection. In addition to the transactions to receive material into inspection and move it from inspection, these transactions include:

  1. Reject and return; this transaction normally reduces the inspection quantity and reopens the purchase order.
  2. Reject and scrap; this transaction normally reduces the inspection quantity and scraps the material-the purchase order is not reopened.
  3. Reject and rework; this transaction typically reduces the inspection quantity and creates a manufacturing order for the rework.

An unplanned receipt transaction that increases the balance on hand.

An unplanned issue transaction that reduces the balance on hand.

Separate transactions for scrap, inventory adjustments, etc. or a reason code on other planned and unplanned transactions so that scrap and inventory adjustments can be identified as such.

A way to reduce the volume of transactions required to support a high volume environment. Common methods include:

  1. Back flushing
  2. Synchro-flushing
  3. Pick complete issue transactions
  4. Pick complete issue transactions to summarized picking lists
  5. Interfaces to bar code readers
  6. Preprinted or pre-punched transactions

A multiple location inventory transaction system with the following characteristics:

  1. All inventory transactions update the balance in the specified locations as well as the total quantity on hand.
  2. A method exists for identifying the primary location and any permanent locations.
  3. A method exists to identify and purge temporary locations when the balance in the location is zero.
  4. A method for identifying locations containing material which is unuseable and which should not be part of the beginning available balance.
  5. Multiple items can be stored in the same locations.
  6. A transfer transaction exists to move material from one locations to another.

The ability to handle less than whole units in stock (for example, 17.5 pounds of steel).

A cycle counting system that includes:

  1. A control group for finding the causes of inventory record errors.
  2. A method of sampling the inventory records so that existing errors can be purged and the inventory accuracy measured. Several common methods are:
  3. Random sampling

    ABC sampling

  4. Process control sampling

Cycle counting transactions to report the cycle counts and update the inventory records, and that supports a two step cycle counting process.

An inventory transaction history by item that shows all transactions that affected the balance on hand and the balance before and after the transaction.

An inventory transaction history by item and locations that shows all the transactions that affected the balance on hand in the location, and the balance before and after the transaction.

A transaction history listing by item that shows all transactions that updated balances, quantities, and fields affecting the master scheduling, material requirements planning, and capacity planning calculations.


Scheduled Receipt Subsystem

The ability to maintain scheduled receipts. The transaction system for maintaining scheduled receipts typically includes:

  1. Add a scheduled receipt
  2. Change a scheduled receipt
  3. Delete a scheduled receipt

Each scheduled receipt contains at least four pieces of information:

  1. Item number
  2. Due date
  3. Quantity
  4. Unique identifies (authorization number, order number, etc.)

Multiple scheduled receipts (line items) on purchase orders.

The add schedule receipt transaction can release an order unplanned, release a planned order, or release a firm planned order. The date and quantity can be changed at the time the order is release.

The transaction that adds a scheduled receipt by releasing a planned order finds the existing planned order and deletes it.

The transaction that adds a scheduled receipt by releasing a firm planned order finds the existing planned order and deletes it.

The transaction that adds purchased orders allows multiple scheduled receipts for each order.

The transaction that changes scheduled receipts can change either the date or the quantity of the order. Changes in either the date or quantity are reflected in the component allocation.

The transaction that deletes scheduled receipts will close a scheduled receipt and remove the component allocations regardless of the order status.

Provide schedules receipts without work orders.

A split transaction that will split a single scheduled receipt into two or more scheduled receipts, each with it’s own due date. The split transaction creates additional scheduled receipts, allocations and open order detail, and prorates any prior activity across the new records.

A method for releasing a rework scheduled receipt that does not allocate components.

A method for releasing and tracking non-material purchases.

A picking list organized by scheduled receipt showing the components that need to be issued.

The ability to print purchase orders if necessary.

A summarized picking list showing the components that need to be issued to a group of scheduled receipts.

Logic to assist in choosing the location from which components should be picked. Sample logic:

  1. List locations with small on-hand balances first.
  2. List locations with on-hand balances sufficient to cover the required quantity.
  3. List all locations for each item
  4. List all locations with a non-zero balance on hand.

Maintain a total allocated quantity (or summarize the individual allocations to compute the allocated quantity when needed) for each item.

Provide transactions to add, change, and delete allocations.

A component availability check that compares the quantity required tot he quantity available (on-hand less allocated) for each component in a bill of material, flagging those short.

A method to release an order regardless of component availability.

The ability to check availability without having to create the scheduled receipt or FPO first.

Component availability checking logic that will properly account for inventory on phantom items.

Logic to create individual allocations when a scheduled receipt is created.

Fair shares logic to distribute product to all locations giving equal service. Fair shares logic has the ability to eliminate safety stock (time), order quantities, and forecast demands at each receiving location to compute equal service.

Allocation logic that will allocate the quantity (or partial quantity) on hand for a phantom item if an on-hand balance exists and before blowing through to allocate lower level components.

A way to store and maintain a final assembly schedule for product made to order from modules or pseudos.

Logic to keep the master schedule in balance after the final assembly has been released. This logic creates dummy scheduled receipts to replace the master schedule orders (FPOs and gross requirements) already in the system.

Logic to group all the operations associated with the pseudos that are a part of a final assembly schedule, and back schedule them to derive operation schedules.

Logic to provide a simple status report that could be used as an interim daily dispatch list.


Firm Planned Order Subsystem

The ability to maintain FPOs. The transaction system for maintaining FPOs typically includes:

  1. Add a FPO
  2. Change a FPO
  3. Delete a FPO

Each FPO contains several pieces of information:

  1. Item number
  2. Start date
  3. Due date
  4. Quantity
  5. Lead time
  6. Unique identifier (authorization number, order number, etc.)
  7. Code to identify whether bill of material deviations are present.

A FPO can be created from a planned order, or directly without a planned order existing in the system.

The transaction that creates a FPO from a planned order finds the existing planned order and deletes it.

A mechanism exists to create and update the component gross requirements coming from firm planned orders, when the firm planned orders change. This can be done in several ways:

  1. By exploding the FPOs in MRP (if no bill of material deviations are indicated)
  2. By updating component requirements as part of the FPO transaction logic.
  • Creating component requirements by exploding the bill of material and attaching the requirements to the FPO-FPO add transaction
  • Rescheduling the component requirements by reading the requirements attached to the FPO and rescheduling them to an earlier or later dates, smaller or greater quantities-FPO change transaction
  • Deleting the component requirements by reading the attached requirements and removing them- FPO delete

Routing Subsystem

The ability to store and maintain item-work center relationships. The transaction for maintaining the routing would typically include:

  1. Add, change, or delete a work center
  2. Add an operation to a routing
  3. Change an operation
  4. Delete an operation

An unlimited number of operations in any routing.

A way to vary the time basis for the standard hours stored in the routing.

Additional routing transactions;

  1. Multiple delete: delete a complete routing
  2. Multiple replace: replace one work center with another in all occurrences
  3. Same-as-except: copy a routing and attach it to another item

Work center where-used relationships maintained as the routing is maintained.

Routing reports or displays that include:

  1. Routing inquiry
  2. Work center where-used listing

Net change capacity requirements planning: a mechanism to update capacity requirements when the routing changes. Common methods include:

  1. In the routing transaction system when the routings are changed.
  2. Deleting all planned orders for the item and associated capacity requirements for the work centers as part of the routing transaction processing, and recreating them in the logic of capacity requirements planning.
  3. Marking items with routing changes in the routing transaction processing, with logic in capacity requirements planning to match current routing against old gross requirements; adding, changing, or deleting requirements as required.
  4. Marking items with routing changes in the existing transaction processing, with logic in capacity requirements planning to delete any existing gross requirements, then recreate them as necessary from the planned orders and the current routing.

Scheduling and Dispatching

Maintain an open routing in an open order detail file for each manufacturing scheduled receipt. This includes:

  1. Logic to copy the routing and attach it to the scheduled receipt when the scheduled receipt is created. This function is normally part of the order release transaction or a daily batch run.
  2. Provide add, change, and delete transaction to maintain the open operations.

Logic to copy the routing for any phantom components and merge it into the other operations for the parent item.

A method for producing shop paperwork if necessary.

A simple back scheduling calculation to compute operation schedule dates (operation start date, operation due date).

Normal and simple scheduling rules that provide the following:

  1. Number of shifts and hours per shift for each work center
  2. Number of machines (people) in the work center and the number used in this operation
  3. Paperwork preparation and parts issue
  4. Move and queue time for operations in different work centers
  5. Move and queue time for operations run successively in the same work center
  6. Run and setup time for each operation
  7. Outside processing operations
  8. Scheduling deviations and overlapping operations

Back scheduling logic that takes into account overlapping, concurrent operations.

A comparison of calculated lead time (from back scheduling) and the planning lead time (from MRP).

Logic that recomputes the operation schedule dates on a manufacturing scheduled receipt if the order is rescheduled to an earlier or later date.

Logic that recomputes the operation schedule dates on a manufacturing scheduled receipt if operations are added, changed, or deleted from the order.

Logic that recomputes operation schedule dates for all orders if factors like planned queue times change for a work center.

A shop movement transaction system that includes:

  1. Move transaction
  2. Operation complete transaction

Additional shop movement transactions:

  1. Labor (partial completion) transaction
  2. Combination operation complete and move transaction
  3. Combination labor and move transaction

Operation status codes by operation to identify current job status in an operation based on shop movement transactions.

Daily dispatch list showing the shop schedule, including operation schedule dates and order due dates.

Daily dispatch list by:

  1. Work Center
  2. Department

Jobs shown on the dispatch list distinguished by status, usually showing jobs present in the work center first, followed by jobs scheduled but not currently in the work center or department.

Look ahead horizon to show jobs to a work center (department) within a few days.

Order status report or display listing summary and detail information for each manufacturing schedule receipt. Summary information includes:

  1. Item number
  2. Order quantity
  3. Due date
  4. Order number

Detailed information includes:

  1. Operation number
  2. Operation description
  3. Setup and run hours
  4. Operation due date
  5. Operation status

Capacity Requirements Planning

A capacity requirements planning calculation that extracts the open operation records from the open order detail file and generates capacity requirements based on the order quantity, run, set up and tear-down times, and the operation schedule dates.

A CRP calculation that back schedules planned orders through the routing to generate capacity requirements. The back scheduling calculation takes into account the order quantity, set up, run, and tear-down times to compute capacity requirements.

The back scheduling calculation for planned orders is consistent with that used when the scheduled receipt is created.

A method for generating capacity requirements from FPOs. This can be done in either of several ways:

  1. Extract open operation records from the open order detail file (this assumes that the open operation records are attached when the FPO is created).
  2. Back schedule the FPOs through their routings to generate capacity requirements (assumes that the routing is not attached to the FPO when it is created).

The back scheduling calculation for FPOs is consistent with the one used for scheduled receipts and planned orders.

Compute capacity requirements in standard hours.

Compute capacity requirements based on crew sizes.

Some method for slotting the capacity requirements. For example:

  1. Spread capacity requirements out over the duration of the operation (from operation start date to operation due date).
  2. Show all capacity requirements at the start of the operation.
  3. Show all capacity requirements at the due date of the operation.

A method for calculating capacity requirements for more than one resource in an operation.

A capacity requirements summary report or display that displays the totals of the capacity requirements by work center or department. This report displays:

  1. Work center (department) descriptive information
  2. Capacity planning periods
  3. Capacity required
  4. Capacity available
  5. Number of hours/under available capacity

Time periods used for capacity requirements planning:

  1. Weeks
  2. Days
  3. Two-week buckets or larger

Display a moving four-period average capacity requirement on the summary capacity planning report.

A way to vary the available capacity in each period.

A capacity requirements detail display (printed or on-line) showing the individual orders that make up the total capacity requirements.

A way to group items into families with common or similar set-ups.

A listing of items with common set-ups for grouping by manufacturing family.

Routing deviations tied to an order provided in any of several ways:

  1. Serial number effectivity logic
  2. Lot number effectivity logic
  3. Attaching a routing to a FPO and providing a transaction system to add, change, and delete these operations as needed.
  4. Other

Input Output Control

Provide information by work center for input/output control:

  1. Planned input (eight periods, four past, one current, three future minimum)
  2. Actual input for the last four periods plus the current
  3. Planned output (eight periods, four past, one current, three future minimum)
  4. Actual output for the last four periods plus the current
  5. Planned queue (four periods as minimum)
  6. Tolerances on input, output, and queue deviations

A mechanism to maintain planned input periods:

  1. Transactions to update the planned input buckets based on an agreed upon input rate (preferred method)
  2. Logic that averages the capacity requirements over a short period, say four weeks, and updates the planned input buckets for the current and future periods based on this average capacity requirement.

A mechanism to maintain actual input from the input from shop movement transactions. When a job is moved to a work center, the shop movement transaction adds the standard hours being moved to the actual input for the week.

A method to maintain planned output. This method is normally a system of transactions to update the planned output buckets based on an agreed upon rate of output.

A method of maintaining actual output from shop movement transactions. When a job is moved to a work center, the labor transaction or operation completion transaction adds the standard hours to the actual output for the week.

A method of calculating the current queue in the work center, using it to compute:

  1. Planned queue for future periods
  2. Actual queues for prior periods

A mechanism to shift the input/output control data to different buckets as the calendar rolls (i.e. earliest past due period is dropped, and the next oldest period is shifted to the oldest period).

Provide a display of the input/output control information including:

    INPUT

  1. Planned input
  2. Actual input
  3. Cumulative deviation

    OUTPUT

  1. Planned output
  2. Actual output
  3. Cumulative deviation

    QUEUE

  1. Planned queue
  2. Actual queue
  3. Cumulative deviation

Provide tolerances on input, output, and queue deviations.


Supplier Scheduling and Related Purchasing Activities

A vendor scheduling display showing the scheduled receipts that have been authorized for the vendor, as well as planned and FPO beyond the quoted lead time.

A method to store different sources for each item, and the percentage split that the source supplies.

A method of prorating or communicating proration of the planned orders on the vendor schedule when an item has several sources.

A follow-up report or display to remind a buyer or planner to check the status of the order prior to its receipt.

A way to compute and summarize the capacity requirements for each vendor.

A vendor negotiation report showing planned purchases over some specified period and showing information to prioritize the orders and then work on negotiation.

A mechanism to store and maintain two dates for each line item on a purchase order. One date is the date the order is due at the receiving dock while the other is the date the order is due in the stockroom.

A receiving/inspection lead time to compute the difference between the purchase e due date and the dock date.

A daily dispatch list for the inspection department. The report format is the same as that for a work center dispatch list.

A support for outside processing operations including:

  1. A special type of purchase order that is excluded from MRP
  2. A method for tying outside processing purchase orders to their corresponding open shop orders
  3. Purchase order transactions that update the outside processing purchase order as well as the shop floor status of the shop order.
  4. Exception logic to notify a person any time an outside processing purchase order needs to be rescheduled.

Distribution Resource Planning

The ability to store and maintain distribution relationships. The transaction system for maintaining distribution networks would typically be:

  1. Add a distribution network relationship
  2. Change a distribution network relationship
  3. Delete a distribution network relationship

An unlimited number of source or receiving DC’s in any single level distribution network.

Additional network transactions:

  1. Multiple delete: delete a complete distribution network
  2. Multiple replace: replace one component with another in all usages
  3. Same as except: copy a distribution network and attach it to another parent item

Where-used relationships maintained as the distribution network is changed.

Distribution network reports or displays that include:

  1. Single level distribution network
  2. Multi-level distribution network
  3. Single level where-used listing

Logic to update the low level code based on changes to the distribution network.

A continuity check to verify that a SKU is not structured to itself, directly, or indirectly. The low-level logic can provide this function.

Low-level code updating done either:

  1. On-line as changes occur
  2. In a batch run just prior to an DRP explosion (for all items or by exception-only for those items which have been added to distribution networks or higher level bills of materials).

Net change DRP: A mechanism to update gross requirements when the distribution network changes. Common methods include:

  1. In the distribution network when the network is changed
  2. Deleting all planned orders for the item in the receiving warehouse and the associated gross requirements for the supplying warehouses as part of the distribution network transaction processing and recreating them in the logic of DRP.
  3. Marking items with distribution network changes in the distribution network transaction processing, with logic in DRP to match the current distribution network against the old gross requirements; adding, changing, or deleting requirements as required.
  4. Marking items with distribution network changes in the distribution network transaction processing, with logic in DRP to delete any existing planned orders and exploded gross requirements, and then recreate them as necessary.

Engineering effective dates and effectivity logic to tie engineering changes to a specific date. For items in warehouses active on the specified dates, gross requirements are generated by the order explosion logic. For items in warehouses that are not active on the specified dates, the components would be bypassed and no gross requirements generated.

Distribution network tied to a specific order provided in any of several ways.

  1. Serial number effectivity logic
  2. Lot number effectivity logic
  3. Attaching gross requirements to firm planned orders and providing a transaction system to add, change, and delete these requirements as needed.
  4. Other

A method of calculating planned distribution (or interplant) orders for SKUs in the receiving locations. This logic is identical to that of MRP.

Each SKU at each location can have its own on-hand balance, lot sizing rule, safety stock, forecast, lead time, etc.

A method for posting the planned distribution or interplant orders as distribution requirements to the MPS at the supplying facility. Typical methods include:

1. Using a single database and bills of materia to represent the distribution network. Each SKU at each location has a separate item number (product item number and location identifier)

2. Using a single database and a source code on each item/location to identify the manufacturing source for that SKU. A computer program translates planned orders for one location into demands on the MPS at the source location.

3. Using separate databases and a computer program or programs to translate planned orders at the DC’s to demands on the MPS.

Maintain distribution information on scheduled receipts that are in transit to branch warehouses or branch plants. This includes the item number, quantity and date, status of the movement, whether or not the items have been shipped, shipper, means of shipment, freight cost, value of the shipment, insurance, etc.

Use the DRP or interplant orders to generate transportation requirements. This calculation extracts the unshipped distribution orders, planned and firm planned distribution orders and generates requirements, typically in weight, volume and number of pallets, for each destination.

A transportation planning summary report or display that displays the total of the transportation requirements by destination and shipping method. This report displays:

1. Destination and shipping method

2. Transportation planning periods

3. Required weight, volume, and number of pallets

4. Available transportation capacity in weight, volume, and number of pallets

5. Amount over/under available capacity

Time periods used for transportation planning:

1. Weeks

2. Days

A way to vary the available transportation capacity each period.

A transportation planning detail display (printed or on-line) showing the individual shipments that make up the total transportation requirements.

A way to define a fixed shipping schedule to each distribution center.

Logic to adjust planned distribution orders to the next earlier ship date based on the fixed schedule.


Tool Planning and Control

1. Maintain tooling information:

A. Tooling descriptive information.

B. Tooling required by operation.

C. Tooling on-hand balance.

D. Tooling scheduled receipts.

E. Show tooling on shop paperwork.

2. Provide an MRP display for tooling.

3. Provide a capacity planning report

including exceptions to show any

conflicts in the use of tooling.

Maintain descriptive information for tooling.

Maintain a cross reference of tooling required by operation.

Transactions to maintain the on-hand balance for tooling.

A way to store and maintain scheduled receipts for tooling.

Show tooling on shop paperwork.

Provide a MRP calculation and MRP displays for tooling.

Provide a CRP calculation and CRP reports (including exceptions) to show any conflicts in the use of tooling.


Financial Planning Interfaces

Logic to calculate current inventory value and display boh the total on-hand value and the individual items that make up that total.

Logic to calculate work in process inventory and display both the total work in process inventory value and the individual items and orders that make up that total.

Logic to calculate the projected inventory value (on hand and work in process) for future time periods, and display both the total projected inventory value and the individual items that make up that total.

The projected inventory value should be based on the projected on-hand balance from MRP.

The projected work-in-process inventory value is based on:

  1. A simple proration of added labor during the lead time period for an order
  2. A precise calculation of labor added at each of the operation in the routing.

Logic to calculate projected cash disbursements for material expense, based on both scheduled receipts and planned orders.

Logic to calculate projected cash disbursements for labor, overtime, and variable overhead expense based on the CRP, labor and overtime rates and variable overhead rates.

Logic to calculate projected billings from the master scheduling system.

Projected billings computed from:

  1. Sales forecast (make-to-stock product)
  2. MPS (make-to-order product)

A method for allocating fixed overhead expense.


Simulation

Provide a method for simulating the effects of changes to the S&OP and MPS. The simulation logic should be the same as that used in the operating system.

Present information in a form that is easy to analyze effectively:

  1. Separate net change simulation logic for all functions
  2. Regenerative or net change logic for resource requirements planning, capacity requirements planning, and financial planning: net change MRP logic.
  3. Regenerative or net change logic for resource requirements planning, capacity requirements planning, and financial planning: regenerative MRP logic to compare the old plan and old exception messages to the new plan and new exception messages to identify changes that need to be reviewed.

Allow people to evaluate the simulation at the same time others are working with the original plan:

  1. A simulation process that stores and maintains the delta value of any simulation
  2. A simulation process that uses work files

Performance Measurements

A measurement of inventory record accuracy based on the daily cycle count activity. This measurement takes into account reasonable tolerances.

A measurement of forecast accuracy. This measurement takes into account reasonable tolerances.

A measurement of customer delivery performance. This measurement takes into account reasonable tolerances.

A measurement of MPS delivery performance. This measurement takes into account reasonable tolerances.

A measurement of shop delivery performance. This measurement takes into account reasonable tolerances.

A measurement of transportation performance. This measurement takes into account reasonable tolerances.

A measurement of vendor delivery and quality performance. This measurement takes into account reasonable tolerances.

 

 

Back to Gray Research Home Page