Monday 11 February 2013

Whats best Precise and Imprecise in BOM ?

Precise and Imprecise BOM Structures: Lets research little bit about what is precise and imprecise in BOM and which will suit for Indian Industries.

What is BOM?
BOM (Bill of materials) , It is a list of materials required by a contractor to complete a contract, or by a supplier or vendor to complete an order. Or it is a list of all raw materials, parts, intermediates, sub-assemblies etc. (with their quantities and description) required to construct, overhaul, or repair something. See also bill of quantities. Bill of Materials is commonly known as BOM in Mechanical, Aerospace, Automobile, Construction Industries etc. 

BOM Types: There are several types of BOM around the globe namely SBOM (Service Bill of Materials), MBOM (Manufacturing Bill of Materials), EBOM (Engineering Bill of Materials) etc.

BOM Teamcenter point of view: BOM in Teamcenter refers most of the time to EBOM which is Engineering Bill of materials, where the designer will create list of items required for assembly and defines the quantity of it. Most of the companies has enabled automatic BOM option, which means whenever an assembly saved in UG/related CAD application, the BOM is created according to the assembly and attached to the item revision.

BOM is viewed with a Teamcenter module called PSE or also called as Structure Manager in Teamcenter 8 onwards. There are 2 main differences in BOM structure.
1. Precise BOM
2. Imprecise BOM

What is precise BOM?
Precise BOM is a type of BOM where item revision are linked together which forms a static structure, which will not get updated based on any criteria or also called revision rules.

Revision Rules: Those are rules defined for loading the BOM in desired format based on the rule guidelines set by yourself. E.g.: If I want to see only latest released item revision in the BOM structure you need to set a revision rule and load based on it.

What is Imprecise BOM?
Imprecise BOM is a type of BOM where item are linked together which form a dynamic structure and can be loaded based on the revision rule.
How do I know am i using Precise/Imprecise BOM?
Just add a column called precise, if the assembly is precise you will get ‘y’ in the column



Which BOM is most useful and why?
It all depends on client and situation, for ex: Just guess which BOM structure can be used
1. In case of released item where do you want to freeze the changes in BOM structure.
2. While the assembly undergoes modification continuously and not yet released.
3. The Assembly is need to be reviewed for latest working and released
4. Need to know only released item in the BOM structure. So it all depends on situations, you can also easily toggle between Precise/Imprecise BOM from Edit menu in Teamcenter.