A slightly convex (raised centre) or concave (slightly dipped centre) pan is not necessarily a manufacturing fault. In many cases, changes to the shape of a pan can occur as a result of normal use and temperature-related stresses.
What Causes a Pan to Become Convex or Concave?
One of the most common causes is thermal shock, which occurs when cookware is exposed to sudden changes in temperature.
Examples include:
- Placing a hot pan under cold running water
- Immersing a hot pan in a sink of cold water
- Moving cookware rapidly between very hot and cold environments
Thermal shock is not solely related to overheating. Even when used at normal cooking temperatures, rapid cooling can place stress on the materials within the pan.
Why Can This Happen with Clad Cookware?
Clad cookware is constructed from multiple bonded layers of metal, typically stainless steel with an aluminium core.
These metals naturally expand and contract at different rates when heated and cooled. If the pan experiences sudden temperature changes, the layers can react unevenly, creating stress within the cookware structure. Over time, this may lead to slight distortion or warping of the base.
Is a Slightly Concave Base Normal?
Yes. Many high-quality clad cookware products are designed with a very slight concave base when cold.
This design allows for the natural expansion of the metals during heating. As the pan reaches cooking temperature, the base should move closer to flat, helping to maintain even contact with the hob and promote consistent heat distribution.
When Should I Be Concerned?
If you notice that oil, butter or water consistently runs to the outer edges of the pan during cooking, even when the pan is fully heated and positioned on a level hob, this may indicate that the base is no longer sitting as intended.
This can potentially affect:
- Heat distribution
- Cooking performance
- Browning and searing results
- Stability on the cooking surface
How Can I Prevent Distortion?
To help maintain the performance and shape of your cookware:
- Allow the pan to cool naturally before washing.
- Avoid placing a hot pan under cold water.
- Do not immerse hot cookware in cold water.
- Use appropriate heat settings for your cookware.
- Avoid sudden, extreme temperature changes wherever possible.
Need Further Assistance?
If you believe your cookware is affecting cooking performance or you are unsure whether the level of convexity or concavity is normal, please contact our Customer Service team and provide:
- Photos of the pan base
- The cookware model or product name
- Details of the hob type being used
- A description of the issue experienced during cooking
Our team will be happy to review the information and provide further guidance.