双杆吊货装置 [水运] union purchase

双杆吊具 burtoning rig ; yard and stay rig

双杆联吊 burtoning system

双吊杆操作系统 union purchase system

双杆联吊装置 union gear

双杆联吊设备 yard and stay tackle

双杆联吊起重系统 union purchase system

双杆联吊起货索 married fall

双千斤索吊杆装置 twin span derrick

双连杆式悬吊系统 dual link type suspension