On the Geometrics tab, all geometric related data is displayed.
Geometric 1 is not a mandatory field. After a commodity code is assigned, this field is populated by the first available geometric table that has a geometric relation with the selected commodity code. Depending on the type of specification items and on the method used to standardize the idents, this results in unique spec item idents only if the idents are created from a geometric table containing unique diameter input values. If this is not the case, a filter table has to be assigned. See the section "Ident Filter" in this documents.
From1 - To1
Size range for the first nominal size of a component.
From2 - To2
Size range for the second nominal size of a component. This only has to be filled in very rare cases such as for nipples and weldolets. In all the other cases, the component is used for all size 2 sizes depending on the filter or ident table.
As mentioned in the overview chapter of this document, the ultimate aim of a piping specification is to define, based on specification items, a list of idents which are uniquely defined over the nominal diameter sizes.
In the below screen shot, a typical geometric table is shown that is not unique based
on the nominal diameter sizes.
Each nominal diameter appears four times with different schedules, which means with different wall thicknesses. Based on the engineering work of a specification engineer, the schedule for each nominal size is calculated for the specification and stored in a filter table.
Working with filter tables has the advantage that the S.40.12 tables (geometric tables used for the creation of idents) can be created independent of the specification.
The filter table represents the applicable schedule over all sizes. A typical best practice is to create filter table codes in accordance with the specification code in order to make maintenance easier.
This filter table can be assigned to the specification via the specification header geometrics or the geometric 1.