China FAMOUS Steel Engineering Company Company News

The steel structure is a structure composed of steel materials and is one of the main types of building structures. The structure is mainly composed of steel beams, steel columns, steel trusses and other components made of steel and steel plates, and the joints, bolts or rivets are usually connected between the components or components. Beijing professional steel structure production and installation company is widely used in large factories, stadiums, super high-rises and other fields because of its light weight and simple construction. 1. Before the steel structure is installed, it is necessary to inspect various records and reports such as the factory certificate, the material test report, the non-destructive inspection report of the weld, and check whether the appearance of the component meets the design requirements, and the problem should be corrected immediately. 2. Drawing the steel structure installation flow chart and installing according to the flow chart. Before the installation, the accuracy of all anchor bolts should be checked, and the space position and design drawings should be corrected in time to ensure the anchor position. The accuracy. 3. The order of component installation should be carefully designed to form a rigid body as soon as possible so as to continue to maintain a stable state and to facilitate the elimination of errors in the installation of steel structures. 4. Component lifting should be carried out for necessary checking. For members with small lateral stiffness, measures should be taken to stop the distortion and damage. 5. During the installation of the column or steel structure, the beam and support should be installed in time, and if necessary, the cable rope should be temporarily fixed. 6. The installation of the steel column should pay attention to the influence of the temperature difference on the verticality of the component. The adjustment side quantity is based on the verticality of the standard column determined first, and the other columns are reviewed. 7. When the column is installed, the positioning axis of each column must be directly drawn from the control axis of the ground. The top axis of the next column should not be used as the positioning axis of the upper column. 8. Steel structure installation site welding environment, welding position, high-altitude operation, air temperature and humidity are unfavorable. Therefore, it is easy to produce weld defects, so measures must be taken to overcome the adverse effects. Unqualified weld rework No more than two times. 9. The torque wrench used for high-strength bolts must be calibrated before use. It should be calibrated after use. Once the calibration torque error is found to exceed the allowable range, the wrenches that are applied by the wrench are unqualified. The high-strength bolts shall be inspected after the final screwing, and the nuts may be tested one by one by a small hammer tapping method. The torque should also be tested 10. After the steel structure is installed and corrected, the gap between the column bottom plate and the top surface of the foundation should be grouted in time to make the bottom plate and the base surface tightly contact. 11. After the installation of the entire steel structure is completed, it shall be checked and accepted according to the requirements of “Code for Acceptance of Construction Quality of Steel Structure Engineering” (GB 50205-2001).

Due to the increase in steel production in China, more and more enterprises are beginning to use the steel structure design steel structure factory. The steel structure factory is divided into light steel structure workshop and heavy steel structure workshop. The main load-bearing components are composed of steel, including Steel pillars, steel beams, steel structure foundations, which are different from traditional brickwork buildings, have the following characteristics: 1. The steel used in the steel structure design workshop is plastically good. Under normal circumstances, the structure will not suddenly break due to accidental overload or partial overload. The toughness of the steel is good, so that the structure has strong adaptability to dynamic loads; 2. The steel used in the steel structure design workshop is uniform in material and high in structural reliability; 3. Steel structure design The steel used in the workshop has high strength, light weight structure and large span of manufacturing plant, which can be made into a structure with a large span; 4. The steel of the steel structure workshop has weldability, which greatly simplifies the connection of the steel structure and is suitable for manufacturing various complicated shapes; 5. High degree of industrialization in the manufacture and installation of steel structures The production of steel structures is mainly carried out in specialized metal structure factories, so the production is simple and the precision is high. The manufactured components are transported to the site for installation, with high assembly degree, fast installation speed and short construction period. Of course, the steel structure design factory also has other special features, such as heat resistance, non-refractory, and poor corrosion resistance, and should avoid the humid environment as much as possible. However, in general, the steel structure plant has high strength, large span, short construction period of steel structure construction, and correspondingly reduced investment cost, which is more and more welcomed by enterprise manufacturers.

According to the data of the General Administration of Customs on May 8, the export of steel products in China was 6.326 million tons in April 2019, a decrease of 0.1 million tons from the previous month, down 2.3% year-on-year. In the first four months, China exported 23.351 million tons of steel, an increase of 8.3%. . In April, China imported 1.0 million tons of steel, an increase of 101,000 tons from the previous month, down 4.3% year-on-year; in January-April, China's cumulative imports of steel was 3.896 million tons, down 13.4% year-on-year. In April, China imported 80.772 million tons of iron ore and its concentrates, a decrease of 5.752 million tons from the previous month, down 2.6% year-on-year; from January to April, China imported a total of 34.208 million tons of iron ore and concentrates, down 3.7% year-on-year. . In April, China exported 582,000 tons of coke, down 18,000 tons from the previous month, down 28.4% year-on-year. From January to April, China exported 2.585 million tons of coke, down 13.8% year-on-year.

Prestressed concrete box girder bridge with corrugated steel web, also known as corrugated steel web PC bridge, refers to box girder with corrugated steel plate instead of concrete web of prestressed concrete box girder as web. Its remarkable feature is 10~ A 20 mm thick steel plate replaces a concrete web having a thickness of 30 to 80 cm.   Origin In the 1980s, France first designed and built a new composite bridge-cognac bridge with corrugated steel webs instead of ordinary concrete box girder webs. Later, several Maupre viaducts, Asterix bridges and Dole corrugated steel were built. Web bridge.   Development Since the 1990s, Japan has also studied this type of bridge. Based on the similar bridges in France, it has built a series of bridges such as the New Bridge, the Bengu Bridge [1], and the Pine No. 7 Bridge. There are continuous beam bridges and continuous rigid frame bridges, which widen the scope of use of such bridges and develop design and construction techniques.   Domestic There are no real bridges for corrugated steel web prestressed concrete composite box girder. At the same time, several bridges of this type have been built in France/Germany, especially in Japan. Design and construction techniques are increasingly mature. Prestressed concrete composite box girder with corrugated steel web is especially suitable for continuous box girder with medium and large span. With the development and deepening of the analysis and research of this structure in China, as well as the reference to foreign engineering practice experience, the prestressed concrete composite box girder with corrugated steel web will be applied in the construction of bridges in China.

Bailey Bridge is a fast-assembled bridge designed by the Highway Planning and Design Institute of the Ministry of Communications on the basis of the original British-made Bailey Steel Truss Bridge. It is a decomposable and fast-erecting standard bridge. High-strength steel is fully welded. The main beam is a decomposable light truss. The truss is connected by a single pin. The components are interchangeable and light in weight. It is easy to transport and disassemble. It can also be assembled according to the requirements of span and load. The type of assembled steel bridge is a well-prepared and comprehensive emergency transportation support assembled steel bridge. Applicable to 5 kinds of loads such as automobile-10, automobile-15, automobile-20, crawler-50, and trailer-80.

1. 321 type steel bridge Bailey net lane width is 3.7 meters; 200 steel bridge net lane width has two kinds: standard width is 4.2 meters (convenient for special vehicles); 2. The staggered arrangement of the joint between the chord and the truss is strengthened to reduce the inelastic deformation caused by the pin hole clearance, and the pre-arching method is adopted to greatly reduce the vertical deflection of the bridge span. The 321 type steel bridge cannot be arranged in this way, and the deflection of the whole bridge is larger than that of the HD200 steel bridge. 3. The bolt connection member adopts the method of positioning and fixing of the guide sleeve to increase the connection precision of the product, the guide sleeve is sheared, the bolt is pulled, the service life of the bolt is improved, and the safety of the steel bridge is ensured. 4. HD200 wind-resistant rod is made into a single type, and connected with the beam to improve the overall stability of the steel bridge. 5. The horizontal support frame of the HD200 steel bridge is fixed between the horizontal support frame and the truss piece. This ensures that the whole bridge has no side bends and the whole bridge is well equipped with pre-camber. 6. Steel bridge components are less convenient for assembly, disassembly, transportation and storage. 7. In the case of large span, the 321 type steel bridge obviously exceeds the HD200 steel bridge in the amount of steel used. The 321 type steel bridge combination form is: three rows of single-layer reinforced type, and its weight is: 57.2 tons. The HD200 steel bridge combination form is: double-row single-layer reinforced type, its weight is: 54.8 tons, which saves 2.4 tons of steel than the 321 type steel bridge, and its steel bridge Bailei sales net lane also increases to 4.2 meters, which is convenient for vehicles. by. 8. When the special load is required, the 321 type cannot bear, and the HD200 steel bridge can pass the maximum load of 60 tons

Our company recently exported a number of container houses to Christchurch, New Zealand. The price of this flat packing container house is between $2,000 and $6,000 for a 20-foot container. We can do interior decoration according to customer's needs, including floor, wall panel, roof panel, furniture, bathroom and kitchen. Doors and windows can also be customized. This kind of container house can be used as an office, a living room, a bedroom, an exhibition room, etc., and other requirements can be met. Because it is easy to manufacture and easy to install, whether it is a company or an individual, I believe there is always something that suits your needs.

On April 9, 2019, the construction workers of the Pingtan Strait Rail-Road Bridge used the rare good weather to speed up the construction progress. The Pingtan Strait Rail-Road Bridge is 16.34 kilometers long. The upper level is a six-lane highway and the lower level is a two-lane railway. It is China's first truly dual-use cross-sea bridge for roads and railways. It is also the most difficult in the world. The public-rail dual-use cross-sea bridge, the project is expected to be fully open to traffic in 2020. The Pingtan Strait in Fujian has a complex climate and was once known as the “bridge-free zone”.

Due to its own advantages, steel structures are widely used in modern buildings such as bridges, industrial plants, and high-rise buildings. In a large number of engineering construction processes, steel structure engineering has also exposed many quality problems. This paper mainly focuses on Liaoning's recent problems in the main experience of steel structure acceptance and completion acceptance and rectification measures. 1. Production problems of components The plate used for the portal steel frame is very thin and can be used up to 4 mm. The cutting of multiple sheets should be preferred for cutting and avoiding flame cutting. Because cutting with flame will cause great wave deformation at the edge of the board. At present, most manufacturers of H-beam welding use submerged arc welding or semi-automatic welding. If the control is not good, the welding deformation should occur, causing the member to bend or twist. 2. Column foot installation problem (1) Pre-embedded parts (anchor bolts) Problem phenomenon: overall or layout offset; the elevation is incorrect; the threaded fasteners are not protected. Directly causing the bolt holes in the steel column bottom plate to be misaligned, resulting in insufficient thread length. Measures: The steel structure construction unit cooperates with the civil construction unit to complete the work of the embedded parts before the concrete is poured. The relevant dimensions must be reviewed and secured. (2) The anchor bolt is not vertical: the horizontalness of the bottom of the frame column is not the same, the anchor bolt is not vertical, and the horizontal error of the pre-embedded anchor is too large after the foundation construction. After the column is installed, it is not in a straight line, and it is difficult to see the appearance of the house. It brings errors to the installation of the steel column, and the structural stress is affected, which does not meet the requirements of the construction acceptance specification. Measures: The installation of anchor bolts should be carried out by first leveling the bottom plate with the lower adjusting bolts, and then filling it with secondary grouting without shrinking mortar. Therefore, when anchor bolt construction, fixed anchor bolts such as steel bars or angle steel can be used. Welding into cages, perfecting the support, or taking other effective measures to avoid moving the anchor bolt one bit when pouring the foundation concrete. (3) Anchor bolt connection problem: the column foot anchor bolt is not tightened, the pad plate is not welded to the bottom plate; some anchor bolts that do not expose 2 to 3 thread buttons. Measures: Welding bolts and nuts should be adopted; outside the chemical anchors, fireproof coatings and heat insulation should be thickened to prevent anchoring performance during fire; the foundation settlement observation data should be supplemented. 3. Connection problems (1) High-strength bolt connection 1) The bolt equipment surface does not meet the requirements, resulting in poor bolt installation, or the degree of bolt fastening does not meet the design requirements. Cause Analysis: 1. There are impurities such as floating rust and oil on the surface, and there are burrs and welds in the bolt holes. 2. The bolt mounting surface is still defective after being processed. Solution: 1. The surface of high-strength bolts, such as floating rust, oil stains and bolt holes, should be cleaned one by one. It must be rust-proofed before use, so that the bolts for assembly should not be used in the formal assembly. Bolts should be kept and distributed by a special person. 2. Handling the assembly surface should take into account the construction and installation sequence, prevent repeated, and try to handle it before lifting. 2) The bolt thread is damaged, and the screw cannot be screwed into the nut freely, which affects the assembly of the bolt. Analysis of the cause: The thread is severely rusted. Solution: 1. Before use, the bolts should be selected, cleaned and rusted for pre-matching. 2. The bolts damaged by the thread cannot be used as temporary bolts. It is strictly forbidden to force the screw holes. 3. Pre-opted bolt assemblies shall be stored in sets and shall not be interchangeable during use. (2) On-site weld phenomenon: the quality is difficult to guarantee; the design requires full penetration of the first and second welds without ultrasonic flaw detection; the main beam and column of the floor are not welded; the arc runner is not used for welding. Solution: Before welding the steel structure, check the welding certificate. Select the welding strip according to the design requirements. Use the welding rod according to the instructions and operating procedures. There must be no cracks or welds on the surface of the weld. First and second welds. There shall be no stomata, slag inclusions or crater cracks. The first-order weld shall not have any defects such as undercut and under-welding. The first and second welds shall be non-destructively tested as required. The welder's steel shall be inspected at the specified welds and parts. . Unqualified welds shall not be disposed of without authorization. After the modification process is determined, the number of weld repairs in the same part shall not exceed two times. 4. Component deformation problem (1) The component is deformed during transportation, and there is a dead bend or a slow bend, which makes the component unable to be installed. Cause Analysis: 1) The deformation caused by welding during the production of the component generally exhibits a gentle bend. 2) When the component is to be transported, the support point is unreasonable, such as the underlay is not vertical, or the stacking site is sunken, causing the component to produce a dead bend or a slow deformation. 3) The deformation of the component during transportation due to collision, generally showing a dead bend. Precaution: 1) When manufacturing components, measures to reduce welding distortion are used. 2) In assembly welding, measures such as deformation in the opposite direction are adopted. The assembly sequence should be in accordance with the welding sequence. The assembled tires should be used to set up enough brackets to prevent deformation. 3) Pay attention to the reasonable arrangement of the pads during transportation and transportation. Solution: 1) The deformation of the member is usually bent by mechanical correction. Use a jack or other tool to correct or supplement with oxyacetylene flame after grilling. 2) When the structure is subjected to slow bending deformation, it is corrected by oxyacetylene flame heating. (2) The full-length distortion of the steel beam members after assembly is more than the allowable value, resulting in poor installation quality of the steel beams. Cause Analysis: 1) The splicing process is unreasonable. 2) The size of the assembled node does not meet the design requirements. Solution: 1) Assemble the components to be assembled, and the bottom surface of the components should be leveled to prevent warpage. The assembly workbench shall be at the level of each fulcrum, and welding deformation shall be prevented during the welding. In particular, the final assembly of the beam section or the stairway should be adjusted after the positioning welding. Note that the size of the joint should conform to the design, otherwise the component may be distorted. 2) The components with poor rigidity should be reinforced before turning over the welding. After the components are turned over, they should be leveled, otherwise the components cannot be corrected after welding. (3) The member is arched, the value is large or less than the design value. When the value of the arching of the component is small, the beam is bent downward after installation; when the value of the arching is large, the elevation of the extruded surface is likely to exceed the standard. Cause Analysis: 1) The component size does not meet the design requirements. 2) During the erection process, it is not corrected based on the measured value and the calculated value. 3) Bridges with small spans have a small degree of arching and are ignored during assembly. Solution: 1) Perform each step of inspection strictly according to the allowable deviation of steel structural members. 2) During the erection process, the rods are installed and the construction of the joints at the site is completed, and the upper crown is measured, and other adjustments are made during the construction. 3) In the small assembly process, the cumulative deviation should be strictly controlled, and measures should be taken to eliminate the influence of the welding shrinkage. 5. Steel structure installation problem (1) Pre-control measures for the foot of the steel column Before the steel column is hoisted, the basic elevation should be strictly controlled, the measurement should be accurate, and the basic surface should be carefully leveled according to the measured value; if the secondary grouting method is used, the bottom of the column foot should be watered. Hole (also used as vent hole), use steel pad to flatten the bottom of the steel column, and pre-position the steel plate of the column foot according to the design elevation, and then take the secondary grout. (2) Pre-control measures for steel column displacement Before pouring the concrete foundation, the pre-embedded bolts are clamped according to the design position by the shaping chuck to prevent displacement when the concrete is poured; the reserved holes of the lower steel plate should be enlarged to determine the hole position. Make a reserved hole. (3) The vertical deviation of the column is too large. The pre-control measures shall be hoisted in accordance with the calculated hanging point, and the lifting method of two points or more shall be adopted. Temporary fixing shall be carried out during lifting to prevent hoisting deformation; after the column is in place Temporary support should be added in time; vertical deviation should be corrected before fixing. Conclusion: Only in the process of construction management, strengthen the training and training of technical personnel and workers on the standardization and operation procedures, effectively prepare for the start of construction, strengthen the quality control and supervision and inspection during the construction process, and actively exert various aspects such as construction and supervision. The role of the sub-projects in the process of acceptance, in order to ensure the overall quality of steel structure engineering.

On March 30th, 2019 (10th) China Steel Development Forum was held in Beijing. The theme of the forum was “Quality, Brand, Management and Innovation of Steel Enterprises”. Liu Zhenjiang, secretary of the Party Committee and Secretary General of China Iron and Steel Association, attended the forum and pointed out in his speech that "the situation in 2019 is more complicated than that in 2018. From the first quarter of the steel industry, downward pressure has emerged, not optimistic, there must be urgency. Consciousness, there is no need to be pessimistic. The downward pressure on corporate efficiency is increasing, and the pressure on the operation of the industry is naturally increasing. We are not expecting such a high efficiency this year, and we are not willing to be in trouble again. Stable operation has become a top priority. We must control the pace of production, strengthen industry self-discipline, pay attention to market changes, strengthen market monitoring and pre-judgment, and attach importance to benefit analysis." Yin Ruiyu, former deputy director of the Ministry of Metallurgy and academician of the Chinese Academy of Engineering, talked about the high-quality strategic thinking of the steel industry from the perspective of brand. He believes that the strategic orientation of China's steel industry transformation and upgrading is to become an irreplaceable basic raw material industry for the development of the times; to become an indispensable supporting industry for China's economic and social development; to become a low-carbon coexistence with society, cities and ecological environment. Green industry. Yin Ruiqi pointed out that branding is an important strategic fulcrum for instigating the transformation and upgrading of the steel industry. It is recommended to promote branding by managing “management” technology. Gao Xiangming, president of China Iron and Steel Association, secretary of the party committee and chairman of Taigang Group, shared the practice of Taigang to build high-quality stainless steel products at the meeting: adhere to the strategy to lead development, deep focus and implement stainless steel development strategy, and build a global stainless steel industry leader Enterprises; adhere to innovation-driven development, promote the transformation of science and technology innovation from chasing, running to leading, to create a leading edge in stainless steel technology; adhere to high standards to establish enterprises, leading the industry's technological development and upgrading of stainless steel standards, to create high-quality stainless steel products Play a market-oriented role, closely track downstream demand, deepen technical services, and build a core base for high-end specialty stainless steel production. Li Xin, vice president of China Iron and Steel Association and president of the Metallurgical Industry Planning and Research Institute, made a concluding speech. About 500 people from all levels of government departments, research institutes, steel companies, and related upstream and downstream enterprises attended the conference.