How to unlink part from equipment in SAP via t4s?

[Former Member]

i have Equipment 500043

in mapping file im using following statement to attach part to equipment

set ::SAPDat(EQUI:DATA_GENERAL:CONSTTYPE) $material_id

it is also there in field called 'ConstType' in equipment's structure tab in SAP.

but how can i remove that part.?once it is attched it is not going to remove even value is NULL

Thanks in advanced