letters patent of utility model for the high efficiency detachable wide channel plate heat exchanger

letters patent of tube shell type double spiral baffel plate heat exchanger

letters patent of welded wide channel plate heat exchanger

letters patent of utility model for the main pump oil cooler of Hualong No.1 Nuclear Power Plant

untility model patent certificate of heat reuse integrated heat exchange unit

letters patent of pipe support fixed belt forming mould for heat exchange unit

letters patent of humidification type horizontal plate air cooler

letters palent of anti-condensation high efficiency and high voltage electrostatic precipitator