Gaskets have tolerances on their key attributes. The tolerances are dictated by a combination of material characteristics and manufacturing processes. If you want your new gasket to seal properly, it's important to understand how these tolerances work and if they are within your parameters.
Key Gasket Attributes
Dimensions are often critical for sealing devices. However, unless a gasket goes in a channel, the outer dimensions aren’t usually critical to success. What does matter, though, are the bolt hole positions, bolt hole diameter, and the inner shape. The inner shape of the gasket should not impede or intrude into the flow.
Gasket Material Thickness
Tolerances are dependent on material type (PTFE, Silicone, Neoprene, EPDM, etc.) and industry standards for your specific application.
Manufacturing Process Tolerances
Gasket sheet