ASME PTC 4.4-2009

The object of this Code is to establish procedures for conducting performance tests of Heat Recovery Steam Generators (HRSGs) used to recover gas turbine exhaust energy. The steam generator may include supplemental firing. This Code provides standard test procedures yielding the highest level of accuracy consistent with current engineering knowledge and practice. (a) The purpose of this Code is to determine the following: (1) capacity of the unit at specified conditions. (2) energy input from gas turbine exhaust and supplementary firing. (3) gas side pressure drop. (4) steam/water side pressure drop(s). (b) This Code provides methods for converting the performance at test conditions to specified operating conditions. A determination of any or all of the performance items listed above may be used for the following purposes: (1) checking the actual performance against guarantee. (2) comparing these items at reference conditions. (3) comparing different conditions or methods of operation. (4) determining the specific performance of individual parts or sections of the HRSG unit. (5) comparing the performance when firing different fuels. (6) determining the effects of changes to equipment. Also, this Code addresses steam generators whose primary function is to recover heat from gas turbine exhaust. Methods noted in this Code may also be used for testing other heat recovery units which may include the following: (1) Units heating water only. (2) Units using working fluids other than water. (3) Units obtaining hot gas heat input from sources other than gas turbines. (4) HRSGs with fresh air firing capability. This Code does not cover the following testing: (1) fired steam generators which primary function does not include the recovery of heat from gas turbine exhaust. These are addressed in PTC 4 and PTC 34. (2) auxiliary equipment such as pumps and fans that are addressed in PTC 8.2 and PTC 11, respectively. (3) deaerator performance that is addressed in PTC 12.3. (4) equipment noise emissions that are addressed in PTC 36. (5) gaseous emissions to atmosphere. (6) steam purity.