Abstract: The nozzle loads overstep the limiting values of the hot exchanger in the finished calculation of the primary loop piping in China Advanced Research Reactor (CARR), and the supports setting needs to be optimized. Integrating the piping structural characteristics and using the powerful functions of the PIPESTRESS software, the essential reasons of nozzle loads overstepping the limiting values were found, the principles considering the static loads first and then the dynamic ones were adopted to adjust the supports, the realizable restricting measures were gotten through the repeated contrastive analysis, the demands of the nozzle loads were satisfied so that the equipments were protected and the piping safety capability were improved. For protecting the equipments the weight supports near nozzle should be placed as far as possible, seismic and thermal loads have different demands to supports setting, which should be considered together, all the factors such as nozzle loads, reaction force on supports, local installation should be integrated to set the supports.