MRP processing
Use this function as a modelling tool for planning current and future material requirements.
MRP (Material Requirements Planning) helps you match your supply of materials (components) to demand for your parent products (independent and dependent requirements, ORLICKY's theory). MRP searches through orders such as sales orders and work orders to assess the potential component requirements. If work orders have been raised, MRP uses the bill of material (BOM) to analyze the requirements for each level in the bill.
For every potential requirement, MRP establishes existing replenishments by checking existing resources such as purchase orders and work orders. These requirements and replenishments are then processed in chronological order, and the rolling stock balance calculated.
By studying the potential requirements and replenishments across one, or multiple sites, MRP can establish actual requirements, thereby preventing stock shortages.
With direct links to the purchasing and manufacturing functionality, MRP can raise purchase order and work order suggestions. These order suggestions ensure that materials are available at the required times to fulfil your schedule. By only ordering items when there is a requirement for them, stock levels are kept to a minimum.
When to run Material Requirements Planning
You can run MRP at any time. However, since an MRP run can take up a considerable amount of processing power and time it is best to work out a procedure. Decide how often to run MRP by considering the following points:
- How much information is required.
- How often the information is required.
- How much of an overhead MRP is to run.
- How frequently sales orders, work orders and purchase orders are processed, and stock levels change.
Running MRP daily may not be a worthwhile operation as the results may only differ slightly. MRP may be more useful if run weekly or monthly. There are no strict rules. Running MRP once a year is also quite feasible. If you use a weekly production schedule you should run MRP at least weekly.
As well as running MRP at regular intervals you can run MRP in response to ad hoc changes.
As MRP can take several hours to run it is a good idea to run MRP overnight. Alternatively, you could run MRP over the weekend.
Definition of the requirements and resources managed by Sage X3
Requirements (Demand) |
||
Order type |
Description |
Source (Generator) |
Sales order (SO) |
||
SOS SOP SOF |
Sales order suggestion (sales forecast) Sales order planned Sales order firm |
Consumption forecast Customer order Customer order |
Transfer request (TP) |
Note: Mirrors the transfer replenishment from the requesting site - see Resources (TRx) |
|
TPS TPP TPF |
Transfer request suggestion Transfer request planned Transfer request firm |
TRS TRP TRF |
Material in work order (MW) |
||
MWS MWP MWF |
Material in work order suggestion Material in work order planned Material in work order firm |
MRP Planned production release Firm production release |
Subcontract service (SC) |
||
SCS SCP SCF |
Subcontract service suggestion Subcontract service planned Subcontract service firm |
MRP with load calculation Production release with subcontracted product Production release with subcontracted product |
Material subcontracting (MS) |
|
|
MSS MSP MSF |
Material subcontracting suggestion Material subcontracting planned Material subcontracting firm |
MRP Planned subcontract order Firm subcontract order |
Resources (Supply) |
||
Order type |
Description |
Source (Generator) |
Purchase order (PO) |
||
POS POP POF |
Purchase order suggestion Purchase order planned Purchase order firm |
MRP Purchase request / Purchase contract Supplier order |
Work order (WO) |
||
WOS WOP WOF |
Work order suggestion (suggested production) Work order planned Work order firm |
MRP Planned production release Firm production release |
Subcontract order (EO: External order) |
||
EOS EOP EOF |
Subcontract order suggestion Subcontract order planned Subcontract order firm |
MRP Launch subcontract order planned Launch subcontract order firm |
By-product in work order (BW) |
||
BWS BWP BWF |
By-product in work order suggestion By-product in work order planned By-product in work order firm |
MRP Planned production release Firm production release |
Transfer replenishment (TR) |
||
TRS TRP TRF |
Transfer replenishment suggestion Transfer replenishment planned Transfer replenishment firm |
Enterprise planning workbench / Planning workbench MRP Customer order |
Prerequisites
Refer to documentation Implementation
Screen management
The MRP processing function contains a single screen in which you select a processing date and one, or multiple storage sites (warehouses).
Entry screen
You use this screen to specify what to include in the MRP processing run.
You can define a processing date in the past, or in the future.
You can run MRP for a single site, or multiple storage sites (warehouses). If running MRP for multiple sites, the position of a site in the selection table is important. In effect, MRP processes the sites successively, that is, if the selection order is site A, then site B, then site C, the calculation will be performed first for site A, then for site B, then for site C.
The processing order can be important if MRP calculations generate transfer (intersite) suggestions.
Processing
The MRP processing run analyzes the potential requirements (demand) and replenishments (supply) across the defined sites. The sites are processed in the order defined in the runtime table, and actual requirements established according to specified time buckets. MRP then uses a product-supplier selection hierarchy for suggestions created for purchase order suggestions, and subcontract order suggestions to determine the preferred (default) supplier by site, as follows:
If the MRP processing run fails to nominate a supplier the supplier must be selected manually when creating a purchase order, or subcontract order from the MRP results in an associated function. See MRP results below.
- If the ITMBPSFCY - Supplier-site referencing parameter (ACH chapter, REF group) is set to Mandatory:
- The default supplier for the product-site record.
- The supplier that is not "blocked" and that has the highest priority level defined on the product-site record.
- If ITMBPSFCY is set to Optional or Not used, and the ITMBPS - Supplier referencing parameter (ACH chapter, REF group) is set to Mandatory:
- The default supplier for the product record.
- The supplier that is not "blocked" and that has the highest priority level defined on the product record.
- Subcontract orders only: The Subcontract BOM code (XBOMALT field) defined for the product-supplier, or if the product-supplier has no subcontract BOM code defined, the BOM code defined in the MRP calculation parameters.
Where the potential material requirements includes a version-managed product, MRP will always issue a suggestion for the exact version of a product if components have been allocated (detailed allocation). If, however, a shortage of safety stock is found, MRP will always issue a suggestion for the latest active version.
MRP "manages" phantoms as subassemblies to consider the planned consumption of residual stock. Once the MRP results have been written to the Orders table (for use in workbenches and inquiries), the material in work order suggestion (MWS) and work order suggestion (WOS) for the phantom are removed from the Orders table (or the MWS reduced if stock is consumed), and the phantom component MWS demands are reattached to the WOS for the parent product. This ensures the correct relationship between the parent and the phantom components in the workbenches.
Reminder: Parameters that impact MRP
Product data
Stock management (GESITM): A product must have the Stock management field (STOMGTCOD) set to Managed, or have the Management mode as By order (STDFLG field).
- If a product is stock managed, MRP will produce a suggestion by period that regroups all the requirements over the period.
- If a product is managed By order, MRP will produce a suggestion by order for the parent product and the components, if the components are managed for the order.
Product-site data
Product-site (GESITF): The fields in the Management and Planning sections must be completed, noting the following:
- Planning block:
- Firm horizon: Suggestions are generated after this horizon.
- Demand horizon: Forecasts are not taken into account within this horizon.
- Lead times block: MRP uses these fields to determine positioning and order duration.
- Lead times (Production, Quality control, Purchase): Are expressed in days.
- Reduction factor: Used to correct the production and reorder lead times should the requirement quantity be larger than the economic order quantity.
- Reordering block:
- Reorder mode: Must be set to By MRP.
- Coverage: Is expressed in weeks.
- Safety stock: The economic order quantity (EOQ) and the Technical lot must be defined.
- Stock for project: MRP will consider available physical stock as starting stock for a project need when selected.
Reorder policy
The reorder policy provides selected information for a specific product during the MRP processing run, that is, the type of suggestion, the reorder quantity, the splitting, the safety stock, the use of the replanning analysis.
MRP generates three types of information:
- An order suggestion (WOS, POS, TRS) for a component in the bill of materials (BOM), for instance.
- A requirement triggered from a component requirement (from a requirement for the parent product).
- A work order suggestion triggered from a by-product (BWS).
Suggestion type (explanation of the triggered requirement, or trace)
Compared to a request, an order suggestion is generated for a BOM parent product. This suggestion, along with existing component resources (planned or firm orders), triggers a requirement that is in turn triggered from a component requirement. This is called a trace requirement. The order type will be MSS, MSP, MWS, MWP or MWF, depending on the status of the parent product resource.
Parent product |
Generation of the parent product for the component |
Suggestion for the component |
Requests => Order suggestions |
MWS, MSS |
Order suggestions |
Planned resources |
MWP, MSP |
|
Firm resources |
MWF, MSF |
The trace requirement has the same document number as the order at the origin of the requirement.
MRP handles supply and demand information for phantom products in the same way as for standard BOM components.
You use the Suggestion type field (SUGTYP) to control whether material requirement demand is displayed in the MRP results set. Available values are:
- No processing: No processing on the components and associated parent products.
- With MRP pegging: MRP generates suggestions from the parent products and generates trace requirements and resources, and suggestions for the components.
For phantom products and components, however, generation can be different. - Phantom products: When the quantity in stock of the phantom product is:
- Zero, material requirement demand for phantom products is not displayed in the MRP results.
- Greater than zero, material requirement demand for the quantity in stock of the phantom product is displayed in the MRP results.
- Phantom components: Material requirement demand for phantom components is displayed in the MRP results. When the quantity in stock of the phantom product is:
- Zero, the suggested component quantity is the quantity required to meet the generated order suggestion.
- Greater than zero, the suggested component quantity is the quantity required to meet the generated order suggestion minus the quantity in stock of the phantom product.
- Without MRP pegging: MRP generates suggestions from the parent products without generating trace requirements and resources for the components, that is, there will be no suggestions arising from the trace requirements and resources.
- MRP pegging only: MRP only generates requirements for the parent product. It does not generate suggestions.
For phantom products and the phantom BOM components, however, material requirement demand is displayed in the MRP results. - Phantom products: The suggested quantity is the quantity required to meet the generated order suggestion.
- Phantom BOM components: When the quantity in stock of the phantom product is:
- Zero, the suggested component quantity is the quantity required to meet the generated order suggestion.
- Greater than zero, the suggested component quantity is the quantity required to meet the generated order suggestion minus the quantity in stock of the phantom product.
Reorder quantity
The Reorder quantity field determines the proposed reorder quantity with respect to the requirement. The possible options are:
- Net quantity: Represents the exact quantity of the requirement.
- Minimum quantity without rounding: Represents a minimum suggestion equal to the economic order quantity.
- Minimum quantity with rounding: Represents a suggestion equal to one technical lot. The quantity will be an integer. It can be larger than the Requirement to Technical lot calculated figure.
Splitting
The Splitting field sets up quantity suggestions equal to the technical lot. These suggestions can run in parallel or sequentially.
- None: The suggestion will not be split.
- Parallel: The requirement will be expressed as an amount of the technical lot with the same end date.
- Successive: The requirement will be expressed successively as an amount of the technical lot, scheduled over time.
Requirements calculation parameters
Defining the requirements calculation parameters is mandatory in order for MRP to work properly.
Purchase parameters
Defining the ACH (Purchase) chapter, REF (Referencing) group parameters at the folder level to control the selection of the preferred supplier for purchase order suggestions and subcontract order suggestions.
MRP results
You can view, and print the results of the MRP processing run in many associated functions:
- Enterprise planning
- Planning workbench
- Grouping
- MRP results
- Projected stock inquiry
- WIP inquiry "By product"
- Graphical loads inquiry
Block number 1
Processing (field PROTXT) |
This field displays the type of processing that will be carried out by this function. |
Reference date (field REFDAT) |
This field displays today's date. Leave today's date as the calculation date for this processing run, or type in or select a reference date, either in the past or in the future. The calculation periods and start date for the processing run will be based on this date. |
Display progression (field DSYFLG) |
Select this check box to display the progress of the run. Details of the progress of each product and phase, or stage of the run is displayed. |
Stock site (field STOFCY) |
Use this field to define the storage site (warehouse) at which Material Requirements Planning is required. A storage site has the check box Stock (Details section) selected. You can run MRP for multiple sites. The position of a site in the selection table is important. In effect, MRP processes the sites successively, that is if the selection order is site A, then site B, then site C the calculation will be performed first for site A, then for site B, then for site C. The processing order can be important if MRP calculations generate intersite suggestions. |
Description (field FCYNAM) |
The name of the storage site. |
Batch task
This function can be run in batch mode, but no dedicated standard task is delivered to run it.
Examples
Examples: Order positioning
MRP processing determines the end date and the start date, and positions the orders over time with respect to the requirement date.
Manufactured product, calculation with respect to the product-site record data
WOS end date = requirement date - quality control lead time (on the product-site record)
WOS start date = WOS end date - production lead time (on the product-site record)
Production lead time: 5 days
Quality control lead time: 2 days
Purchased product
POS end date = Requirement date - quality control lead time (on the product-site record)
POS start date = POS end date - order lead time (on the product-site record)
Purchasing lead time: 7 days
Quality control lead time: 2 days
Manufactured product, calculation with respect to the routing data
WOS end date = requirement date - quality control lead time (on the product-site record)
WOS start date = end date - routing time
The quality control lead time should not be defined on the product-site record, if quality control is included in the routing.
The start date is the processing date by default, if the calculated start date is earlier than the processing date.
Impact of the division on suggestions
Firm production (PF): 5 production lead time days
Sales order firm (SOF) 1: 50 parts; Work order firm (WOF) 1: 50 parts
SOF 2: 75 parts; WOF 2: 75 parts
Division in days
Division in weeks
SOF 1: 50 parts; WOF 1: 1,125 parts
SOF 2: 75 pieces
Influence of the firm horizon and demand horizon
Division in days
Firm horizon: 1 week
Demand horizon: 2 weeks
PF product: 5 production days
SOF 1: 50 parts; Date of requirement: Monday, week 1 (WOF no. 1)
This order generates a WOF that will take place after the firm horizon.
SOF 2: 75 parts; Date of requirement: Wednesday, week 2 (WOF no. 2)
Sales order suggestion (SOS) forecast no. 3: 100 parts; Date of requirement: Friday, week 2
This forecast does not generate any work order suggestions (WOS), in effect the requirement date is located within the demand horizon.
SOS no. 4: 125 parts; Date of requirement: Friday, week 3
Examples: MRP results
The Management mode (STDFLG) for this product in the following examples is Available stock.
Example 1
Result of a simple net requirement calculation
Product A
Start stock: 0
Safety stock: 0
Production lead time: 5 calendar days
Period: week
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
50 |
250 |
100 |
|
55 |
105 |
|
250 |
25 |
125 |
|
Projected stock |
50 |
250 |
100 |
100 |
105 |
105 |
0 |
250 |
125 |
125 |
0 |
Example 2
Result of a simple net requirement calculation
Product A
Start stock: 125
Safety stock: 0
Production lead time: 5 calendar days
Period: week
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
175 |
100 |
|
55 |
105 |
|
250 |
25 |
125 |
|
|
Projected stock |
125 |
250 |
100 |
100 |
105 |
105 |
0 |
250 |
125 |
125 |
0 |
The MRP results for a product are dependent on the MRP parameters, the product-site record, the scheduling, the reorder policy associated with the product and the start stock.
Reminder: Parameters that impact MRP
Parameters that can affect the results
Product-site data
Fields in the Management and Planning sections of the product-site record.
Maximum stock
Maximum stock is included if defined in the MRP Requirements parameters (Maximum stock analysis field).
Analysis of the product's maximum stock level is carried out at the end of each period. When the maximum stock level is exceeded, a warning message is generated and displayed in the MRP results inquiry. At the end of the period a VRS ("overstock" warning) is generated for the excess stock quantity. This VRS "warning" is only for information purposes and cannot be converted to a transaction.
Safety stock
Safety stock is included if it is included in the reorder policy associated with the product (the Safety stock field is selected), and if the Ignore safety stock check box in the MRP Requirements parameters is clear.
MRP checks the stock level at the end of the period and issues a suggestion if a shortage of safety stock is found.
Version-managed products: MRP will always issue a suggestion for the exact version of a product if components have been allocated (detailed allocation). If, however, a shortage of safety stock is found, MRP will always issue a suggestion for the latest active version.
Trend safety stock
Safety stock can also be used for trend safety stock if the MRPDYNSAF-MRP seasonalized safety stock parameter (STO chapter, REA group) is set to Yes, the forecast box of the product record is selected, and a trend curve is associated with the product.
Trend safety stock is calculated in proportion with the weight of the processing day in the curve.
Trend safety stock formula: Safety stock * (Period allocation key / Total allocation key) * (Period total weight in months / Period weight in months)
Example 1: Trend safety stock calculation
Product A
Start stock: 0
Safety stock: 350
Number of periods: 12
Period start |
Period end |
Allocation key |
Coefficient |
Trend safety stock |
01/01 |
31/01 |
100 |
0.33 |
117 |
01/02 |
28/02 |
200 |
0.67 |
233 |
01/03 |
31/03 |
300 |
1 |
350 |
01/04 |
30/04 |
400 |
1.33 |
467 |
01/05 |
31/05 |
500 |
1.67 |
583 |
01/06 |
30/06 |
600 |
2.00 |
700 |
01/07 |
31/07 |
500 |
1.67 |
583 |
01/08 |
31/08 |
400 |
1.33 |
467 |
01/09 |
30/09 |
300 |
1.00 |
350 |
01/10 |
31/10 |
200 |
0.67 |
233 |
01/11 |
30/11 |
100 |
0.33 |
117 |
01/12 |
31/12 |
0 |
0 |
0 |
Total allocation key |
|
3600 |
|
|
Example 2: MRP processing run including safety stock
Product A
Start stock: 0
Safety stock: 350
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
400 |
250 |
100 |
|
55 |
105 |
|
250 |
25 |
125 |
|
Projected stock |
400 |
600 |
450 |
450 |
455 |
455 |
350 |
600 |
475 |
475 |
350 |
Technical lot
The technical lot is used in the reorder quantity and the division of the reorder policy.
Example 1
Product A
Start stock: 0
Technical lot: 60 parts
Safety stock: 350 parts
Reorder policy: Minimum quantity with rounding
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
420 |
240 |
120 |
|
120 |
120 |
|
180 |
120 |
|
|
Projected stock |
420 |
610 |
480 |
480 |
550 |
565 |
460 |
640 |
490 |
485 |
360 |
Example 2
Product A
Start stock: 0
Technical lot: 60 parts
Safety stock: 350 parts
Reorder policy: Minimum quantity without rounding
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
400 |
250 |
120 |
|
120 |
120 |
|
150 |
60 |
90 |
|
Projected stock |
400 |
600 |
470 |
470 |
540 |
555 |
450 |
600 |
510 |
475 |
350 |
Reduction factor
The reduction factor of the reorder lead time (reorder lead time = production lead time or purchase lead time) is used to correct the reorder lead time in proportion with the replenishment when the planned or suggested quantity is higher than the economic order quantity.
Corrected lead time = RL * [1 + (quantity/lot - 1) * factor / 100] where RL = Reorder Lead time
This factor is generally used for manufactured products. The supplier lead time is an average lead time, rarely in proportion with the size of a lot.
Example: Lead time correction
Product A
Production lead time: 10 days
Technical lot: 50
Suggestions |
Factor 50% |
Factor 100% |
40 |
10 days |
10 days |
100 |
15 days |
20 days |
150 |
20 days |
30 days |
Coverage
Coverage is used for stock managed products. When MRP is run with coverage, this means that the process analyzes the requirements inside the coverage period in order to issue a global suggestion. This coverage can slide; the suggestion is placed at the beginning of the coverage period, that is at the earliest one coverage period before the requirement date.
Example
Product A
Coverage: 5 weeks
Start stock: 0; Safety stock: 0
Production lead time: 1 week
Requirements expressed per week
Table of requirements expressed over 10 weeks
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
150 |
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
350 |
105 |
105 |
150 |
150 |
125 |
125 |
|
|||
Projected stock |
350 |
405 |
260 |
410 |
510 |
530 |
550 |
400 |
250 |
125 |
0 |
Coverage can be made to depend on the trend when the MRPDYNCOV - MRP seasonalized coverage parameter (STO chapter, REA group) is set to Yes and a trend curve is associated with the product.
Trend coverage is calculated in proportion with the weight of the day in the curve and with respect to the average weight of the applicable period.
Example
1 day: Factor of Day1
1 week: Average of the factors over Week1
1 month: Average of the factors over a month
Product record data: 5 weeks
MRP period (5 days / 3 weeks / 3 months)
Number of days in the year: 365
Period start |
Period end |
Allocation key |
Coefficient |
01/01 |
31/01 |
100 |
0.2505 |
01/02 |
15/02 |
150 |
2.5887 |
16/02 |
28/02 |
500 |
1.1948 |
01/03 |
16/03 |
250 |
3.1064 |
16/03 |
31/03 |
600 |
1.4561 |
01/04 |
30/04 |
400 |
1.0355 |
01/05 |
31/05 |
500 |
1.2526 |
01/06 |
30/06 |
600 |
1.5532 |
01/07 |
31/07 |
500 |
1.2526 |
01/08 |
31/08 |
400 |
1.0021 |
01/09 |
30/09 |
300 |
0.7766 |
01/10 |
31/10 |
200 |
0.5010 |
01/11 |
30/11 |
100 |
0.2589 |
01/12 |
31/12 |
0 |
0.0000 |
Total allocation key |
4700 |
Processing date 02/01
Period start |
Period end |
Applied factor |
Coverage |
02/01 |
02/01 |
0.2505 |
1 week |
03/01 |
03/01 |
0.2505 |
1 week |
04/01 |
04/01 |
0.2505 |
1 week |
05/01 |
05/01 |
0.2505 |
1 week |
06/01 |
06/01 |
0.2505 |
1 week |
09/01 |
13/01 |
0.2505 |
1 week |
16/01 |
20/01 |
0.2505 |
1 week |
23/01 |
27/01 |
0.2505 |
1 week |
30/01 |
30/01 |
0.2505 |
1 week |
31/01 |
31/01 |
0.2505 |
1 week |
01/02 |
28/02 |
1.8917 |
10 weeks |
01/03 |
31/03 |
2.2812 |
11 weeks |
Firm horizon
MRP generates suggestions and induced requirements after the firm horizon, it does not induce requirements or generate suggestions in the firm horizon. Dates are ignored during the firm horizon.
Example
Product A
Firm horizon: 3 weeks
Start stock: 0
Safety stock: 350
|
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
SOF |
|
50 |
250 |
100 |
50 |
105 |
105 |
|
250 |
125 |
125 |
WOF |
|
|
|
100 |
|
|
|
|
100 |
|
|
WOS |
50 |
55 |
105 |
|
250 |
25 |
125 |
|
|||
Projected stock |
0 |
-50 |
-300 |
450 |
455 |
455 |
350 |
600 |
475 |
475 |
350 |
Request/Demand horizon
MRP ignores suggestions from customer orders during the request horizon, or "demand horizon".
Beyond the demand horizon, for each period, a suggestion is issued and MRP takes into account all the firm and planned customer orders as well as the variance between the forecasts and the firm and planned orders.
Example
Product A
Demand horizon: 4 weeks
Start stock: 0
Safety stock: 350
W0 |
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
|
SOF |
50 |
250 |
100 |
50 |
105 |
105 |
250 |
125 |
125 |
||
SOS |
100 |
100 |
100 |
250 |
100 |
100 |
100 |
360 |
100 |
100 |
100 |
WOF |
100 |
100 |
|||||||||
WOS |
400 |
250 |
100 |
105 |
105 |
360 |
250 |
125 |
125 |
||
Projected stock |
400 |
600 |
450 |
450 |
455 |
455 |
710 |
590 |
475 |
475 |
350 |
MRP and replanning
Replanning analysis allows the MRP process to tackle the following questions for a second positioned resource: What is it used for? Should it be moved forward? Should it be postponed? Should the quantity for it be increased? Should the quantity be reduced?
Replanning is not compatible with products managed By order (Management mode field (STDFLG)).
MRP analyzes the first actual requirement during the replanning period around the resource date.
Replanning analysis requires a replanning time period, a replanning rule for each resource (MRP parameter) and a replanning policy (Replanning analysis check box is selected).
The analysis used for each resource is one of the following:
- Not to process
- To issue a message
- Simulation (to modify dates and suggested quantities)
Example
Replanning analysis: 5 weeks
Rule to be applied to firm work orders only
Lead time: 7 calendar days
Ignore reorder policy in replanning: Selected (ticked)
A WOF resource of 100 parts in W3
A resource of 100 parts in W8
Table of the requirements expressed over 10 weeks
W1 |
W2 |
W3 |
W4 |
W5 |
W6 |
W7 |
W8 |
W9 |
W10 |
|
SOF |
50 |
250 |
105 |
105 |
150 |
250 |
125 |
125 |
||
WOF |
100 |
100 |
||||||||
MRP results, in simulation mode |
||||||||||
WOS |
50 |
|
105 |
105 |
150 |
150 |
125 |
125 |
||
WOF |
|
|
100 |
|
|
|
100 |
|
|
|
WOS |
|
|
|
|
|
|
|
|
||
WOF |
250 |
|
||||||||
The process will suggest to increase and bring forward the initial WOF from 100 parts to 250 parts. |
||||||||||
Results in message only |
||||||||||
WOS |
50 |
250 |
105 |
105 |
150 |
150 |
125 |
125 |
||
WOF |
100 |
100 |
||||||||
WOS |
|
|
||||||||
WOF |
250 |
|
|
|||||||
The process will suggest to increase and bring forward the initial WOF from 100 parts to 250 parts, but the dates and quantities will not be modified. |
MRP and expiration
MRP processing integrates expiration dates.
When a lot reaches its expiration date MRP generates a VDS ("trace" warning) to be found in the MRP journal and in the MRP inquiry. The VDS "warning" corresponds to the quantity of the expired lot. It is generated depending on the status assumed by the expired lot and the MRP setup (start stock).
Table of the warnings as based on the MRP setup and the product expiration status.
Expiration status |
||
Start stock |
Q |
R |
A |
VDS |
VDS |
A+Q |
VDS |
|
A+Q+R |
MRP and load calculation
An appropriate MRP setup is used, in parallel with the MRP process, to generate a workload.
The workload is generated according to the routing times over the course of the workload calculation horizon. The division of the MRP periods should be identical to the division of the scheduling periods (see the Scheduling documentation).
The scheduling of dates uses the data from the routing. If the start date is prior to the processing date the system recalculates the end date using backward scheduling (following the scheduling setup) in order for the start date and processing date to be on a par.
After backward scheduling:
When the setup specifies "no backward scheduling", if the start date is prior to the processing date the system modifies the start date (start date = processing date) and displays the message "Delay firm horizon".
Backward scheduling only concerns the released product which can result in a bottleneck at the component level.
Workload display You can view the workload suggestions using the WIP and Graphical loads inquiries.
MRP and transfer option
Transfers are used to place an order with another site in the same company. This relationship is based on a sales and purchase contract between the two sites when generated orders for the requesting site are of type TRx and type TPx for the supplying site.
Successive MRP processes can be interesting when there are regular transfer orders:
- Transfer methodology
A supplier partner must be created on the requesting site. This partner represents the supplying site.
A customer partner must be created on the supplying site. This partner represents the requesting site.
The supplier and customer can be defined on the product record. The product must be defined on each site.
A purchase contract must be created with the supplying site on the requesting site.
A sales contract must be created with the requesting site on the supplying site.
The suggestion type must be defined on the product-site record of the requesting site: Intersite and the site that will be the supplying site.
The Intersite suggestions check boxes in the MRP parameters must be selected.
A TRS is issued during the processing of the requesting site. A matching TPS will be issued in the requesting site. - Transfer operation
The requesting site issues a transfer request (type TRx).
This request can "evolve" depending on the status of origin. A TRS can become a TRP or TRF; a TRP can become a TRF. This change can occur in the planning workbench or enterprise planning workbench of the requesting site.
The change in a TRx status automatically leads to a change in the status of the matching TPx.
The supplying site cannot modify the status of the TPx it has received. The supplying site manufactures or purchases to cover the firm request.
The supplying site ships the order; the requesting site receives the order.
Error messages
In addition to the generic error messages, the following messages can appear during the entry :
Delay firm horizonThis message is displayed when the calculated start date is earlier than the processing date.
Tables used
Refer to documentation Implementation