The pressure rating of Schedule 40 stainless steel (SS) pipe depends on several factors, including the temperature of the fluid being conveyed and the specific grade of stainless steel. However, as a general guideline:

For Schedule 40 stainless steel pipe:

* At ambient temperature (around 70°F or 21°C), it's typically rated for pressures up to 150 psi (pounds per square inch) for standard sizes.
* The pressure rating decreases as the temperature increases. For example, at higher temperatures, the pressure rating may be reduced to maintain safety.

It's essential to consult engineering specifications and standards for accurate pressure ratings, as they can vary depending on the specific application, grade of stainless steel, and other factors. Additionally, local regulations and codes may also dictate the allowable pressure ratings for piping systems.