RVCD-8WN,RVED-8WN,RVGD-8WN,RVID-8WN,RVCD-8DN,RVED-8DN,RVGD-8DN,RVID-8DN,導(dǎo)壓操作平衡活塞,透氣型外部排油帶T-8A插孔泄壓閥