Ship Launching Airbags set Launching World Record
Ship Launching Airbags set Launching World Record
Ship launching marine airbags was used to launch the 58,000 DWT cargo ship successfully in Zhejiang China on Feb.2010. This ship launching project set the new world record of ship launching by marine air bags in the marine engineering industry.
This cargo ship holds 11,800 tons is 199 meters long and 32 meter wide. It is built on a 0.87 degree concrete ramp whose end is a sluice gate. From the water gate to ship’s stern is 15 meters. And the water beyond the gate is 8 meters deep. Total 76 pieces YT-6 type ship launching airbags were employed to complete this project and two 25 tons winches.
For big ship launching and vessel' haul out project, the scientific design from calculation is vital for success. To ensure this DWT58, 000 cargo ship’s safe launching, there are two conditions must be satisfied. Avoiding the “bow decline” during the launch process. Second is the rush distance is controllable when ship is after launch.
It's the largest barges ever launched by Evergreen Marine airbags. Eversafe's engineers gathered together taking 24 hours thingking and consideration to calculate the launching project. From mathematic modeling to computer simulation, every step of launching process were researched carefully. From the water level to weather variety, most conditions were considered for the design.
When finally the arrangement of airbags was decided, Our engineering company find the stern rope must be added to control the rush after launching. So 4 extra stern ropes were demanded to fix on the bollard with 45 degree angle to the ship. And the time of cast anchor is also stated.
At 31 Jan, Eversafe completed the raise of ship and remove of block. At that time, two winches pulled ship from slips but blocks remain stern under the vessel. Estimated that the highest tide of 1 Feb. will at 10:30 AM. So launching time planned at 10 AM.
At 9:30 AM, we began to adjust the inner pressure of ship launching airbags at stern to be 0.12Mpa. Then released wire ropes from winches. At 9:50 AM, the ship launching marine airbags under gravity center and bow were inflated to be 0.15Mpa. Ship began to move slowly by riding rolling airbags.
During the launching, the ship’s incline angle is increasing until the stern floated when the bow entered into deep water already. There is no “bow decline” phenomena occurred seems as what we have calculated. Then ship advanced in the sea for a certain distance its bow anchors was casted. Four stern ropes were trained. So ship moved sideways then it was pushed by two tug boats to mooring.
This successful launching project with marine airbags was not only regarded as world record of airbag ship launching, but also means "Evergreen Maritime are moving forward and growing.
