The crawler crane of the largest radio telescope in Asia assisted the installation
the crawler crane of the largest radio telescope in Asia assisted the installation
China Construction machinery information
Guide: the Shanghai 65 meter radio telescope, the largest omni-directional rotatable radio telescope in Asia, successfully completed the hoisting of the antenna main reflector back frame on April 17. This is the second crane after the hoisting of the pitching mechanism of the 65m radio telescope in place on March 17, 2012, and it is also the three very heavy cranes at high altitude during the construction of the telescope
the Shanghai 65 meter radio telescope, the largest omni-directional rotatable radio telescope in Asia, successfully completed the hoisting of the antenna main reflector back frame on April 17. This is the second crane after the hoisting of the pitching mechanism of the 65m radio telescope in place on March 17, 2012. It is also the hoisting of the three very important high-altitude hoisting projects in the construction process of the telescope, which is the most difficult, demanding and most vivid project. The whole hoisting project is completed by Tianjin lanchao special hoisting engineering Co., Ltd. (hereinafter referred to as Tianjin lanchao), and Terex cc5800 (1000t) and CC (600t) crawler cranes are used for hoisting and installation
according to the local meteorological law that the wind force is small before 11 a.m., the hoisting is carried out in the morning and needs to be completed before the wind force may increase. The difficulty of the project itself and the urgency of time put forward strict requirements for the hoisting organization and the stable operation of the equipment. However, under the careful planning and organization of Tianjin lanchao, who has rich hoisting experience because the strain of the elastic element is in direct proportion to the size of the external force P, the project was successfully completed on time, and the whole hoisting project is perfect
in the early morning of April 17, 2012, the main reflector back frame of Shanghai 65m radio telescope began to be hoisted under the weather conditions. At 6 a.m., the construction personnel entered the construction site and began to prepare for hoisting. At 6:30, with the whistle of the commander-in-chief, the main reflector with a weight of 320 tons and a diameter of 52 meters slowly rose. At 6:50, the lifting height reached 39 meters. At 7:35, the two cranes began to move forward synchronously and slowly without interruption. It took 1 hour and 35 minutes to complete the driving distance of nearly 50 meters. At 9:10, they arrived at the installation position safely. After reaching the initial positioning requirements through measurement and adjustment, they landed slowly at 10:03 and successfully completed the docking with the pitching mechanism. The whole hoisting process lasted for more than 4 hours. The pre installed screw control docking accuracy between the main reflector back frame and the pitching mechanism is better than 2mm. The connection strength between the main reflector back frame and the pitching mechanism, which has attracted much attention, is guaranteed, and the whole hoisting is successfully completed
the size of the main reflector back frame hoisted this time is φ fifty-two × 11 meters, weighing 320 tons. The Terex cc5800 crawler crane used in the project is under the working condition of swsl54+36m, and the CC crawler crane is under the working condition of hswsl54+36m. The two cranes first lift the main reflector of the antenna, and then walk a certain distance synchronously in a straight line. Put the reflector composed of the main pressure pipe of the antenna through the energy accumulator, electric contact pressure gauge, solenoid valve, one-way valve, filter, manual needle valve, connecting and collecting circuit and other components on the designated production foundation. The two crawler cranes stand at the designated position again. After the main reflector of the antenna is hoisted again, the two vehicles walk a certain distance synchronously in a straight line and then put it in place
"On the one hand, the diameter of the whole back frame is large and the weight is heavy, so 4.2 penetration resistant steel balls are required: the mass should be 2260 ± 20g, and the heavy back frame should be lifted in a large working range; on the other hand, in view of the high attention of the project, we must ensure nothing wrong. Therefore, we chose the lifting scheme of Terex cc5800 and CC equipment with superior performance, stability and reliability, and the tower working conditions of the two cranes meet the needs of large-scale lifting." Please. " Zhang Yongliang, deputy general manager and chief engineer of Tianjin blue nest, said
it is reported that the radio telescope system is a major cooperation project between the Chinese Academy of Sciences and the Shanghai municipal government, and is operated by the Shanghai Observatory. The telescope has a diameter of 65 meters, a height of 70 meters, and a weight of more than 2600 tons. The area of the main reflecting surface is equivalent to the size of eight basketball courts. In 2013, the radio telescope system will join the VLBI orbit measurement mission of "escort" for the second phase of the lunar exploration project.
"in 2005, Tianjin blue nest successfully hoisted a 50 meter rotating antenna for Beijing Miyun Observatory, one of the five data collection points of China's annual" lunar exploration plan ". When asked why Tianjin blue nest was selected for the hoisting of this significant project, president Zhang told us that his pride was beyond words. "The evaluation of all parties on the hoisting project of Miyun Observatory under extreme weather conditions is that it is perfect, including the organization and implementation of the hoisting project and close cooperation with other related parties. It is also based on the 2005 project that Tianjin blue nest was selected for this hoisting", "On the other hand, all kinds of Trex cranes and equipment provide a strong guarantee for the Miyun Observatory project, this project and various large-scale classic hoisting projects implemented by Tianjin blue nest. At that time, the Miyun Observatory project adopted the Trex CC Single hoisting scheme, while this project adopted the Trex cc5800 and CC hoisting scheme"
as for the main challenges and solutions faced in this hoisting process, president Zhang summarized them into three aspects: first, the cooperation between the two cranes; The second is the docking of the back frame and the pitch gear; Third, the stability of hoisting. Due to the large area and heavy weight of the back frame, the scheme adopts two crawler cranes to operate at the same time, so how to ensure the "synchronization" of the two equipment is very critical. Therefore, Tianjin lanchao has designed a "shoulder pole beam" for the two cranes to walk synchronously in a straight line, and the load of the two cranes is distributed by 3:2; Secondly, this hoisting requires high accuracy. 12 lifting points need to be arranged on the 65m diameter back frame to accurately hoist it in place, so as to ensure the successful and accurate docking between the back frame and the pitching mechanism; Ensuring the stability and balance of the back frame is also the key to ensure the smooth installation. To this end, Tianjin lanchao has done a lot of work and careful planning from the aspects of scheme design and on-site organization, including tamping the ground, marking the crane driving line and walking scale, installing a level meter and outputting the signal to the display screen of Terex equipment, and the operator monitors the balance state at any time, etc. "The difference is a thousand miles away. The two devices are slightly out of sync, and the balance can't be guaranteed. Such a large back frame with a diameter of 40 meters may have a large dislocation in the air, which can't guarantee the accurate docking in place". "With personnel, equipment, plan and careful organization, we have successfully completed the hoisting", said President Zhang of Tianjin lanchao, who answered our concerns. For this hoisting, "it is still perfect", general manager Zhang commented that "all parties are very satisfied"
"Terex equipment is good", knowing that we pay attention to the use of equipment. President Zhang commented on Terex's equipment, "the large lifting equipment of Tianjin lanchao is Terex's product, and our large representative lifting projects all use Terex's product, starting from the earliest cc1400"
it is reported that the third largest crane in the plan - the lifting of the auxiliary reflector adopts the single crane scheme, with a split weight of 20 tons, a height of 62 meters, and the opening angle caliber of four support legs of nearly 50 meters. It will be completed by Tianjin blue nest company in the near future, and the planned equipment is Terex CC
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