The　vibration　of　the　equipment　in　nuclear　power　unit　will　be　transmitted　to　the　pipeline　connected　with　it，which　is　easy　to　cause　pipeline　failure，gas　leakage　and　other　safety　accidents.　This　paper　designs　a　kind　of　double　dynamic　vibration　absorber（DDVA）with　simple　structure　and　adjustable　mass　to　solve　the　above　problem.　Firstly，the　parameters　of　the　DDVA　are　designed　according　to　the　actual　working　condition　of　pipeline.　After　continuous　iterative　optimization　based　on　fixed-point　theory　and　displacement　amplitude　ratio，the　optimal　stiffness　and　damping　ratio　of　DDVA　are　determined.　Furthermore，the　vibration　absorption　effect　of　the　pipeline　with　DDVA　is　verified　by　finite　element　simulation　and　compared　with　the　pipeline　with　single　dynamic　vibration　absorber（SDVA）.　Finally，the　vibration　absorption　effect　of　DDVA　is　verified　by　bench　test.　The　experimental　results　show　that　the　DDVA　reduces　the　radial　vibration　acceleration　at　the　resonant　frequency　of　pipeline　by　more　than　65%（9　dB）.　The　research　can　provide　a　guiding　significance　for　the　vibration　absorption　design　of　pipeline.　©　2025　Nanjing　University　of　Aeronautics　an　Astronautics.　All　rights　reserved.