Steel Pipe Plant Construction Process Control

1. The arch foot mounting arch of steel pipe factory is the basis of linear control of arch ribs. Positioning of arch leg section should pay attention to its geometric position, axis dimension of arch rib pipe, vertical elevation angle and horizontal verticality to ensure the accuracy of arch rib installation..2. Since the arch foot is constructed together with the concrete of the beam, the steel pipe of the arch rib is positioned before the concrete is poured, and the arch skeleton is fixed by the installed steel skeleton to prevent displacement during the concrete construction. ; Arch feet positioning frame installed linear control range ± 10mm.3. Arch rib installation bracket The steel pipe arch installation adopts the bracket method for installation. It is proposed to use a steel pipe and a steel section to form a bracket. The bottom of the bracket is welded to the embedded part of the concrete box girder, and the top of the bracket is installed with rib adjustment facilities. The operating platform is set on the top of the bracket to facilitate the installation of the ribs.4. The steel ribs installed in the plant ribs are transported to the construction site after being inspected, assembled by trial assembly and passed through the linear adjustment, and assembled and welded into the hoisting segments at the site; welding and damage inspections are conducted using ultrasonic and ray detection methods.. The phenomenon of defects exceeding the standard was found in the welds. According to the exact positioning of the flaw detection personnel, the re-inspection and re-inspection were conducted after the rework processing, until the quality requirements were met. The rib segment lifting shall be performed in sequence from left to right and from both ends from the arch to the vault; during the assembly process, the pre-camber shall be set and the cross bracing shall be installed; the dimension and line shape of each part shall be checked correctly and shall be carried out within the temperature range required by the design. Welding, check weld quality with work.Steel Pipe Arch Installation Notes: 1 erection of the installation of measurement points marked in the factory should be set up, the measurement point is placed in the non-high point of the sub-node pipe (both ends of each lifting section are set), as a mark.2 During the erection of arch ribs, each arch rib will have an impact on the arch ribs that were erected in front of it. Therefore, each arch rib should be retested before the arched rib interface is erected. If the error is found to exceed the limit, It should be corrected in time.3 In order to reduce the influence of temperature on the arch ribs, the measurement time of the staking and acceptance of the arch rib control is usually arranged as early as possible during the time period of 7 to 9 o'clock in the morning and 16 to 18 o'clock in the afternoon; other construction acceptance and construction observations follow the schedule. get on.4 The construction of the closed section is the final link of the arch rib assembly and is the key to the linear control of arch ribs. For the steel pipe arch closed section arch rib section in the processing should be reserved for a certain amount of machining allowance, cutting in the installation. The length of the closing mouth should be accurately measured before the installation of the rib closure section for accurate closing. The measurement of the distance between the closed sections, and the three processes of cutting and installation should be performed at the same air temperature to reduce the influence of temperature on the arch ribs and facilitate smooth closure.5. It is a key process to infuse ribs and ribs with perfusion of arch ribs. It is a key link to ensure the quality of arch rib concrete to ensure the safety of arch ribs. The arch rib concrete is pumped by the pumping jacking method, and it must be ensured that the single arch ribs are filled once. In order to make the concrete filled with steel pipe compact and compensated after shrinkage, the strength of the concrete meets the design requirements, and must be carefully organized and scientifically tested in concrete preparation, production, filling of concrete filled steel tubes, selection of transfer pumps, etc. construction. According to the principles of symmetry and equilibrium loading, the construction of arch rib concrete with arched dome as the symmetric centerline is carried out. In order to ensure the compactness of arch rib concrete, pumping top pouring and pouring method is used to pump and cast steel rib arch concrete at both ends of the arch ribs. During pouring, the concrete is continuously pressed into the steel pipe from bottom to top by the transfer pump. In the arch, there is no need for vibration; until concrete emerges from the top of the pipe to make the concrete in the pipe compact. The lifting order of concrete-filled steel tube is as follows: Each side of the rib is symmetrically poured, and from the bottom up, the pouring sequence is divided into three stages: pumping the lower chord tube, pumping the upper chord tube, and pumping the abdominal cavity.6. The hangers for finished construction of the boom shall be handled by the factory and transported to the site. After the arrival at the site, the site shall be organized to install tension and adjust the cable.

A worker from a steel pipe company, which is located in China.