The depth of a blister cavity, typically expressed in millimetres in machine format specifications.
Also called: blister depth; pocket depth; cavity depth.
Is forming depth the same as forming area or film width?
No. Depth is the pocket’s out-of-plane dimension; forming area is the in-plane format, while web width measures the material across the machine. A large forming area does not itself establish a deep usable cavity.
Keep the dimensional drawing with the specification. A depth value alone does not describe the cavity’s footprint, corners or clearance around a capsule or tablet.
Read the dimensional fields separately
Field
Question it addresses
Forming depth
How deep is the formed pocket?
Forming/format area
What in-plane format can be produced?
Web or foil width
What material width can the machine handle?
Product/cavity drawing
How does the actual product fit within that shape?
Does the quoted maximum apply to every blister material?
Not automatically. A machine can have different depth limits for plastic and aluminium-based forming materials. A listed maximum depth does not establish that every material, format and output combination is usable at that maximum.
For a quotation, retain the material, intended cavity drawing, tool configuration and stated operating basis. Comparing bare maximum numbers can hide a difference in what each supplier has actually specified.
Adequate depth establishes one aspect of product fit. The cavity footprint, formed-wall structure and sealed package still need assessment for the proposed format.
Assess barrier and integrity on the relevant material or package specimen. Neither result can be inferred from cavity depth.