I work in a firm which designs and manufactures vessels and piping. We have landed a project for heat exchangers and it is the first time we are making one. We have ASME LOCAL Branch license for construction of vessels as per BPVC section VIII. Is there any other licensing required to fabricate a heat exchanger apart from this? The design for heat exchanger mentions conformance to API 660 and TEMA "R" Class. I have always worked with ASME and I was not sure whether TEMA and API puts any licensing restrictions on the manufacturer of the heat exchanger.