Every steel drinkware vessel starts as a flat disc. Deep drawing presses that disc through a series of progressive dies, each pass pulling the metal deeper until it becomes a cup. Stamping is the broader family of operations; deep drawing is the specific one that forms a hollow body rather than simply cutting a flat shape.

Wall thinning is the key quality concern. As metal is drawn it stretches and gets thinner, especially near the sidewall and base corners. If thinning is uneven, the wall will not insulate uniformly and the vessel may dent more easily in one spot. A well-run line controls draw ratio, blank thickness, and die clearance so thickness stays within an acceptable band.

For double-wall bottles the process is run twice, or a separate inner wall is drawn and later joined to the outer. Buyers usually care about consistent weight, even wall thickness, and smooth internal surfaces, all of which trace back to this step.

Practical takeaway: Ask your factory how it controls wall thickness during drawing, since that single variable drives insulation, weight, and dent resistance.