Background: Bill of Material Maintenance
Use the Bill of Material Maintenance (MPS) program to enter or change, copy, and delete a bill of material for standard and phantom items. See Road Map for work flow.
This topic has these subtopics:
Types of Bills of Material
The system supports three types of bills of material:
Type |
Use This Program |
Standard, multi-level product structures |
Bill of Material Maintenance (MPS) |
Configured product for final assembly of a custom product structure for a specific sales order |
Configured Product Maintenance (MBM) |
Family bills for forecasting |
Configured Product Maintenance (MBM) |
You can enter standard bills of material for two types of parent items:
Parent Item |
Order Code |
Bypass Code |
Maximum Levels |
Finished good |
0 |
0 |
99 |
Phantom |
1 or 2 |
1 |
15 |
For each parent item, you can specify an Engineering Change Level (ECL) under which you can maintain a unique bill of material. The ECL is a way of distinguishing between different bills of material for the same item. You can assign an ECL to each new engineering release for the parent item. You should indicate the ECL currently in production in the Current ECL field of the item's record in the Branch Item Maintenance (IMB) program. When you release manufacturing orders for the item, the parent item number and ECL combination defines the item to be manufactured.
Bill of Material Example
Suppose that you sell a lighting fixture in a box that includes both the fixture and a bag of installation hardware. In addition, the lighting fixture and the bag of hardware are sometimes shipped separately as spares or replacements. This distinction is made to aid in discussions of product structure, planning, forecasting, and manufacturing order processing.
This is the parts list for the lighting fixture, item number B-100, and its installation hardware, item number B-101. The Level column shows the relationship of components and subassemblies to each other. Note that raw material is the lowest level on this list (4), and the fixture and installation hardware are at the highest level (1).
Item no |
Description |
Qty per |
Bypass code |
Floor stock code |
Level |
B-101 |
Installation hardware |
1 |
0 |
0 |
.1 |
1 |
Wire nut number 6 |
2 |
0 |
0 |
..2 |
3 |
Mounting screw 10-32 RH 1/2" |
2 |
0 |
0 |
..2 |
B/A |
Bracket assembly |
1 |
1 |
0 |
..2 |
2 |
Mounting bracket |
1 |
0 |
0 |
...3 |
Bar stock |
1/8 x 5/8 / 8 ft |
.05600 |
0 |
0 |
....4 |
4 |
Threaded mounting stud |
1 |
0 |
0 |
...3 |
6 |
Mounting nut |
1 |
0 |
0 |
...3 |
B-102 |
Fixture for B-100 |
1 |
0 |
0 |
.1 |
10 |
Bottom lens |
1 |
0 |
0 |
..2 |
Acrylic Stk |
3/32" acrylic sheet |
.07500 |
0 |
0 |
...3 |
5 |
Assembled base plate |
1 |
0 |
0 |
..2 |
5P |
Plate |
1 |
0 |
0 |
...3 |
16 Ga Al Stk |
Raw sheet stock 16 gage alum |
.07500 |
0 |
1 |
....4 |
5R |
Rivets |
2 |
0 |
1 |
...3 |
5S |
Lamp socket |
2 |
0 |
0 |
...3 |
7 |
Frame |
1 |
0 |
0 |
..2 |
16 Ga Al Stk |
Raw sheet stock 16 gage alum |
.05000 |
0 |
1 |
...3 |
8 |
Frame screw |
2 |
0 |
0 |
..2 |
9 |
Side lens |
4 |
0 |
0 |
..2 |
Acrylic Stk |
3/32" acrylic sheet |
.05000 |
0 |
0 |
...3 |
Definition of Terms
This example illustrates these terms:
Parent item |
Defines a relationship between an item and its components. For example, B-100 is the parent of all of these components, B-102 is a parent of item number 5, and 5 is a parent of 5P. |
Component |
Raw material, part, or subassembly that goes into a higher level assembly or other item. For example, item 10 is a component of B-102, and B-102 is a component of B-100. |
Single level |
Defines one relationship in a bill of material. The single-level structure of B-100 consists of items B-102 and B-101. |
Multiple level |
Defines the total relationship of a structure. The multiple-level structure of B-100 is four levels. |
Phantom |
B/A, Bracket Assembly is a phantom assembly. A bypass code of 1 indicates a phantom. The system treats a phantom as a non-inventoried, zero-lead-time item that never actually exists as a unique product in the manufacturing process even though it may be specifically identified as a completed assembly by an engineering drawing. The planning programs normally ignore or bypass a phantom assembly item, and treat its components as though they were structured directly to the next higher item. However, if you enter a forecast for a phantom assembly, the Material Requirements Planning (MRP) program adds the forecast to the gross requirements of each of the phantom's components. Nested Phantoms |
Floor stock |
16 Ga Al Stk and 5R are floor stock items. A floor stock item's quantity is reduced not when you pick the manufacturing order but when you receive it into inventory. |
Levels
You enter a bill of material one level at a time. You first enter the parent item's ECL. Then you enter each of the parent's components.
As an example, you can choose to enter the product structure for item B-100 from the top down, specifying B-100 as the parent item. Next, you would enter the components of B-100: B-101 and B-102. For each component, you must enter the quantity per assembly (in this case, one). This completes the single level bill for item B-100.
You would repeat the same process for each subassembly. For example, you would enter B-101 as a parent item, with B/A, 1, and 3 as its components. Then you would enter B-102 as a parent, with 10, 5, 7, 8, and 9 as its components.
The order codes and bypass codes of parents and components must be compatible. You can use these two combinations:
|
Order code |
Bypass code |
Parent |
0 |
0 |
Component |
0 |
0 |
Component |
1 or 2 |
0 or 1 |
Parent |
1 or 2 |
0 or 1 |
Component |
0 |
0 |
Component |
1 or 2 |
0 or 1 |
You can easily create variations of product structures by copying existing bills of material. You can identify such variations with a different ECL or an entirely different parent item, as appropriate.
Low-Level Codes
When you enter or change a bill, the program automatically updates low-level codes. Low-level codes determine the order in which the system processes component requirements. A low-level code identifies the lowest level in any bill of material at which a particular component appears. The system does not calculate net requirements for a given component until it has calculated all the gross requirements down to that level.
When you change a BOM and exit the program, the system updates the low-level codes. Updating low-level codes is necessary for accurate functioning of the Accumulated Lead Time Calculation (MLT) and Standard Cost Rollup (MCR) programs. The Finished Goods Planning (MFP) and Material Requirements Planning (MRP) programs also require accurate low-level codes. In a rare event that the system encounters an error, it outputs a Bill Exception Report to your default output device. The report lists:
Item number
ECL
Components
Changes that you make in Bill of Material Maintenance do not impact already released manufacturing orders for the parent item; you can use the Material Usage Maintenance (MUA) program to maintain the components of a released manufacturing order.
Effectivity Dates
You can use the Effective date and Expiration date fields to phase out a component from a BOM and phase in another or you can use the Bill of Material Mass Change/Delete (MCD) program close or add components in multiple bills or material.
Component Backflushing
Backflushing is controlled by several system options (maintained in System Options Maintenance - Manufacturing Options). Bill of material component fields Picking warehouse and Picking bin location specify the location from which components are backflushed. Pick per receipt determines if rounding of fractional component quantities is based on the current receipt or by the total quantity received for the order. See Overview: Component Backflushing.
Swap Item
The Swap Item button allows you to swap a component item with a substitute entered for the component. When you swap an item:
The program adds the substitute item to the bill of material and then assigns all the original component's substitutes to the newly added component on the bill of material.
The program deletes the original component from the BOM and all of the substitutes under the original component.
The substitute is added to the bill of material and the effectivity dates move over, as well as the quantity per assembly. All other original data for the old component remains intact after the substitution.
Now the original component is a sub of the item that was just added to the BOM, and all the original items are now substitutes for the replaced items.
Note
If the item's effectivity dates are not in the current time frame, they will be displayed on the substitute selection list.
The Preferred? substitute setting is removed during the swap.
Comments are not transferred and will be deleted when the original component is replaced on the bill of material.
Audit Trail
To activate an audit trail, select one of the files listed below in the Audit Trail Maintenance (XAT) program. The system records all transactions. You can then run the Audit Trails (ATR) program and select that file to print a report of these transactions.
M1: Product Structure
M1H: Product Structure Header
Engineering Change Orders (ECOs)
You can reduce or even eliminate bill of material maintenance and improve your control over changes by using PowerShift's Engineering Change Order (ECO) feature. Changes are made in an offline system where you can track and evaluate costs of the changes and other impacts. The approval system takes control of routing the document for necessary approvals. Once approved, the ECO Processing (ECOP) program moves the ECO to live data. Relevant ECOs and any associated documents can be viewed from Bill of Material Maintenance (MPS).