Clad metal glossary
Half of the friction in a clad enquiry is two people using the same word for different things. This is the vocabulary in the sense the factory uses it.
At a glance
Specification at a glance
| Term | Meaning in this factory | Why it matters |
|---|---|---|
| Clad | Two or more metals bonded across their full face, not plated or glued | The bond is what makes the pan work |
| Ply | A bonded layer; 3-ply is three metals | A 3-ply pan is not three times better than 1-ply |
| Core | The conductive middle layer, usually aluminium | Where thickness and cost are added |
| Skin or face | The outer stainless layer, cooking side or base side | Grade and gauge are specified per face |
| Blanking | Cutting a shape from sheet | Decides yield and edge condition |
| Burr | Raised metal on a cut edge | A start point for a separation in the draw |
| Draw ratio | Blank diameter divided by cup diameter | Sets the elongation the material must deliver |
| Annealing | Controlled heating to soften and relieve stress | Decides formability and flatness |
| Flatness | Deviation from a plane, measured after cutting | A dished disc will not sit in the die |
| Ra | Arithmetic mean roughness of a surface | How a satin or brushed finish is specified |
| Temper | Hardness condition from rolling and heat treatment | Same grade, different behaviour |
| Reference values | Figures typical of the market, not a signed specification | Confirm before tooling |
Why the vocabulary matters commercially
An enquiry that says "3-ply stainless pan material" can be answered with a 2.0 mm budget build or a 3.4 mm professional one. Both are correct answers and the price differs by half. The words that disambiguate are gauge, layer split, diameter and tolerance.
Ply and layer are not the same count
A 5-ply build carries five bonded layers, and two of them may be the same aluminium alloy. A buyer counting distinct metals gets a different number and concludes the supplier is overstating. Count plies as layers, then read the split.
The words that appear in a quotation
Yield, conversion charge, metal basis, surcharge, validity. A quotation that gives a single number per kilo hides all of them. Asking for the split is normal in this trade and no competent supplier refuses it.
The words that appear on a drawing
Nominal and tolerance, pre-press or finished dimension, flatness limit and its timing, edge condition, surface and its Ra range, count per stack. These are the terms that decide whether a shipment is accepted.
Questions
Common questions
What does 3-ply mean exactly?
Three bonded metal layers, typically stainless, aluminium, stainless. The stainless grades on each face can differ, which is why the split is written out.
Is clad the same as plated?
No. Cladding bonds solid metal across the whole face; plating deposits a thin layer. A plated pan cannot be cut and re-bonded at the edge.
What is a reference value?
A figure taken from what the market normally supplies, useful for planning and not a specification. It is confirmed against the drawing before tooling.
What is the difference between temper and grade?
Grade is the alloy, temper is its condition. 304 in a soft anneal and 304 in a hard temper behave differently in the press.
How is surface finish specified?
By name plus an Ra range, then by an approved sample. A name alone varies between mills.