Control procedure of steel bar construction process?
① The factory certificate is provided by the quality inspection department of the steel mill or copied by the supply and marketing department: factory name, heat number (or batch number), steel number, strength, grade, specification, weight, number of pieces, production date and factory batch number; Test data and conclusions of mechanical properties; Chemical composition test data and conclusions; And has the seal and standard number of the quality inspection department of the steel mill. Factory certificate (or its copy, copy) remarks column should be filled in by the construction unit project name and use parts.
(2) The inspection report shall be provided by the legal inspection unit, and the contents of the inspection report include: the entrusting unit, project name, application site, steel grade, appearance mark, factory certificate number, representative number, sample delivery date, original record number, report number, inspection date, inspection items and data, and conclusion (the elongation index shall indicate the standard distance, and the cold bending index shall indicate the bending center radius, bending angle and bending result).
Composition of steel bar
Reinforcement batching is to draw and number a single reinforcement diagram of various shapes and specifications according to the component reinforcement diagram in the design drawing, and then calculate the blanking length and quantity of reinforcement respectively, and fill in the batching list. After the inspection is correct, the reinforcement can be cut. Therefore, the correct ingredient list is not only the guarantee of accurate processing and molding of steel bars, but also the problems such as inadequate extension of steel bar ends and insufficient anchorage length will not occur during the installation of steel bars, thus ensuring the quality of steel bar engineering. Therefore, the reinforcement batching work must be carefully reviewed and strictly controlled.
Cutting and processing of steel bars
In this project, all steel bars are cut and processed on site, so that the length and length are matched, the cutting is reasonable, and the finished product rate of steel bars is improved.
(1) Derusting of steel bars: The surface of steel bars should be clean, so before cutting steel bars, derusting must be carried out to remove oil stains, paint stains, floating skin, rust that can be peeled off by hammering, etc. The rust removal of steel bars in Yuan Pan is completed in the process of cold drawing and straightening; Self-made electric rust remover is used to treat the surface of rebar, and a dust hood is installed to avoid damaging workers' health and polluting the environment.
(2) Steel bar straightening: according to the requirements of construction specifications, steel bars are cold-drawn and straightened with a winch with a traction of 3 tons and ground anchors at both ends; The cold-drawn rate of grade I steel bars should not be greater than 4%; The cold-drawn rate of Grade II reinforcement shall not be greater than 65438 0%. Straightened steel bars should be straight without local twists and turns.
(3) Steel bar cutting: Steel bar cutting equipment mainly includes steel bar cutting machine and toothless saw. , which will be selected according to the size and specific circumstances of the steel bar diameter.
Cutting technology: Match the length of steel bars of the same specification according to the length and make overall arrangement. Generally, the long material is broken first, and then the short material is broken to reduce the short head and loss. When cutting materials, it is necessary to avoid measuring long materials with a short ruler to prevent the accumulation of measuring errors. Therefore, it is advisable to mark the scale line on the workbench and set a baffle to control the size of the cutting material. In the process of cutting, if the steel bar is found to be split, the shrinking head or severely bent head must be removed.
Bending forming
(1) Bending equipment: The bending forming of steel bars is mainly completed by the cooperation of steel bar bending machine and manual bending tools.
(2) Bending forming process: Before the steel bar is bent, for the steel bar with complex shape, the positions of each bending point are marked with a pencil according to the size indicated on the ingredient list. The marking work should be carried out from the center line of the steel bar to both sides; If it is a steel bar with asymmetric sides, it can also pass through one end of the steel bar. If it is different from the other end, it should be readjusted. After checking the size of the cross reinforcement, it can be processed and formed.
Reinforced joint
The steel bar joint is an important link in the whole steel bar project, and the quality of the joint is the key to ensure the normal stress. Therefore, the form of steel joint should be carefully selected, and the principle of selection is reliable, convenient and economical. This project will be selected according to the specific situation.
(1) joint mode The convenient and quick flash butt welding and electroslag pressure welding are preferred for the joint mode of this project. Frame column diameter ≥φ 18 is connected by electroslag pressure welding,