SAP TM comes by default with a given set of location types (plant, customer, ...) and I have been asked multiple times if I could add one or two more. With each release the solution comes with an enhanced set fitting to the business process, for example ocean (obviously port might be a good one) or air.
Often customers want to structure their scenario using location types and miss some. Here is the way to do it customer specific:
1. Add the new location type(s) to the fixed value appends /SCMB/C_LOCTYPE_TM1 and /SCMB/TM_LOCTYPE_TM1 (Don't ask me why there are two... I don't know, but I might follow up on that.) This is switched on for SAP TM using Switch /SCMB/MD_SFWS_TM_FND1, which is attached to the mandatory SCMB - TM Business Function. After adding the values, it is already possible to use the location type when creating a location.
2. To make the F4 help for Locations consider the new types, edit the help view /SAPAPO/V_TLOCNO and add under the tab 'Selection Conditions' your new types with an OR. Take care that the last field LVORM is connected with AND.
https://cw.sdn.sap.com/cw/servlet/JiveServlet/showImage/38-5751-12823/LocationType_03_HelpView.jpg
I am not aware of many spots in TM, where ocation types are used steer anything (UI, process, ...). So new types will not hurt. But I can imagine that this might be used more strictly in the future.
I see another point to consider: Not sure how it is handled in an ERP - TM location integration scenario via CIF. I would guess there it is hard to handle new types, but probably possible (new type on ERP side?).
Cheers,
Marcus