Liquid metal processing management help enterprises

The quality of metalworking fluids can better power processing, how to pass effective chemicals management to extend the use of metalworking fluids cycle, so as to achieve the purpose of reducing enterprise cost,
Has attracted more and more attention from enterprises.Selection of suitable liquid metal processing metal processing liquid emulsion for moderate to heavy duty cutting and grinding, semi-synthetic cutting fluid suitable for most mild to moderate load all types Superfinishingof cutting and grinding, synthetic cutting fluid is only applicable to light cutting load and mild to moderate grinding.
1 from the processing methods for the analysis of higher cutting speed roughing (such as turning, milling and drilling) requirements of cutting fluid has good cooling performance, this should be using semi synthetic cutting fluid and a low concentration of emulsion.In some precision high strength processing (e.g., broaching, tapping, deep hole drilling and processing gear), need cutting fluid has good lubricating property, can choose high extreme pressure emulsion.
2 from the use of tool analysis (1) tool steel tool: This tool heat temperature at 200 ～ 300 ℃, bad thermal stability, high temperature will lose hardness, thus requiring the cooling properties of the cutting fluid, with a low concentration emulsion as appropriate.(2) high speed steel tool: high speed rough cutting, large amount of cutting heat is generated, in order to avoid the workpiece burn and affect the quality of the product, should be used in cooling of synthetic or semi-synthetic cutting fluid; the use of high-speed steel cutting tools in machining, low speed, in order to reduce the friction between the tool and the workpiece, suppressing cutting aneurysm formation, generally take a high concentration of emulsion.(3) cemented carbide cutting tools: such tool melting point and hardness is higher, in general can be used in the processing of emulsion.If heavy cutting, the cutting temperature is high, easy fast wearing of the cutting tool, should be used at this time flow sufficient cooling and lubricating liquid, with 3% ～ 5% emulsion is appropriate (using spray cooling, is better.).(4) ceramic cutting tooSuperfinishingls, diamond and cubic boron nitride cutting tools: these tools higher hardness and wear resistance, cutting generally do not use cutting fluid, sometimes also can use the synthetic cutting fluid.Liquid metal processing costs accounted for about 7% ～ 17% total manufacturing cost, reasonable selection of cost-effective liquid metal processing can be the first step for the enterprise to reduce manufacturing cost.Cutting fluid maintenance and liquid control through good maintenance to extend the life of the processing liquid to reduce cost.In a liquid dispensing before confirming the machine and water clean, and then in the water tank by adding a certain amount of water, and according to the requirements of cutting fluid concentration slowly adding and stirring, until the appearance of uniform.Note: must in the clean water tank blending; must add oil into the water but not vice versa; diluent to adjust the concentration of.In actual use the following parameters will change to control: 1 appearance: appearance changes mainly by external contamination, grey or black primarily involving bacteria and metal particles caused by the saponification, iron processing in common; Brown is and saponification iron; in the liquid surface with creamy material suggests working liquid stability.2 concentrations: control more stringent than better, because of the high concentration of 1% ～ 2% set out under the condition of low running cost.PH: 3 new liquid usually in 9.2 ～ 9.5 between, in the processing of fast will drop to 9 ~ 9.2, every detection helps to extend the working fluid life, because the pH drop is a marker of bacterial infection.PH below 8.7 should adopt add antiseptic measures.4 miscellaneous oil: mainly comes from the machine tool hydraulic and lubricating system, will promote the growth of bacteria, affect the tool life andSuperfinishing the working fluid, should be controlled within 2%, available oil skimmer and centrifugal method to remove.5 of the total hardness of water: depends on the total content of calcium and magnesium ions, too high will affect the working fluid stability and foam level, thus leading to fatty acid soap consumption, we can add water softening or reverse osmosis membrane method to reduce the hardness hardness control, usually at 5 ° dH to 30 ° dH.6: high chlorine content can lead to rust and damaged the working fluid stability, should be controlled within 150PPM, can be added to soften water and concentrated liquid solutions.7: high conductivity can lead to rust and damaged stability of working liquor, affecting tool life.Should be controlled within 5000 μ S/cm, can take part replacement and add softened water solution.Therefore, the metal working fluid life depends mainly on the outside pollution and biological control, practice has proved, good maintenance can make the liquid metal processing prolonging 1 times, produce benefit remarkable.
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Framework structure which classes? Housing construction structure which several types?

Classified according to the structure of housing construction steel structure is the main component of the load-bearing steel material construction, including cable structures.Steel, reinforced concrete structure is the main component of the load-bearing steel, reinforced concrete construction. The reinforced concrete structure is the main component of the load-bearing is constructed of reinforced concrete. Including shell structure template situ structure and the use of sliding mode, up board construction of the reinforced concrete structure of the building. The hybrid structure is the main components of the load-bearing reinforced concrete and brick and wood construction. Such as a beam of the house is made of reinforced concrete, brick wall is load-bearing walls or beams are constructed of wood, the column is constructed of reinforced concrete. Brick and wood is the main component of the load-bearing brick, wood construction. Such as a housing frame wooden room, brick walls, wooden construction. Other structure who does not belong to the above structure houses shall such. Such as bamboo structure, brick arch structure, cave. The main difference is the superstructure, the frame structure, a shear wall, the vertical stiffness of the frame structure is not strong, senior or super high-rise building frame structure especially! To solve this problem it is to use shear walls you can go frame structure, frame structure, residential refers to the load-bearing beams and columns of reinforced concrete poured pounded with precast aerated concrete, expanded perlite, pumice, vermiculite, Tao bad light sheet wall splitting assembled whileResidential. Suitable for large-scale industrial construction, high efficiency, good quality of the project. The frame structure constituted by the beams and columns, smaller member section bearing capacity and stiffness of the frame structure are lower, it's the mechanical characteristics of similar vertical cantilever shear beam, the higher the floor, the horizontal displacement of the slower, high-level framework in aspect both directions under great horizontal force, In this case, cast floor also as a beam working together, the role of the prefabricated floor is not considered, the frame structure of the wall is filled wall, from envelope and separated the role of the characteristics of the framework structure is provided for the construction of the flexible use of space, but poor seismic performance. 1. Frame - shear wall structure, the called frame structure, it is the combination of the two systems of the frame structure and shear wall structure, drawing on their respective strengths, both for building layout provides a greater use of space, but also has good lateral force resisting performance. Wall structure in the shear wall can be set individually, can take advantage of the wall of the elevator shaft, stairwell, tube wells.Therefore, this structure has been widely used in various types of housing construction. 2.The deformation of the superstructure, scissors curved. As we all know, the deformation of the frame structure is relatively small deformation shear, upper layer, the lower layer relative deformation. Shear wall structure deformation for bending, large relative deformation in the upper layer, the lower layer is relatively small deformation. Wall structure, due to the deformation compatibility of the two structures work together to form a curved shear deformation, thereby reducing the pending cut the layer relative displacement ratio and vertex displacement ratio, the lateral stiffness of the structure has been improved. 3. Horizontal load shear walls to withstand. From the characteristics of the force, due to the lateral stiffness of shear wall in the wall structure is much larger than the lateral stiffness of the frame, the horizontal loads, under normal circumstances, about 80% more than in shear wall commitments. Therefore, the frame structure under lateral loads assigned story shears, than the kind of evenly distributed along the height closer to the moment of layers beamed beneficial to reduce the beam-column specifications, to facilitate construction. 

The perfect performance of the of quality cutting fluids in metal processing

A small drop of cutting fluid, related to the processing of the results. Both high-speed processing efficiency, accurate processing effects, or environmental process, the quality of the cutting fluid can bring a good performance. Metal cutting fluid market in recent years, with the metal processing industry is changing and the rapid progress of the metal processing technology, as well as the end user of the continuous improvement of the product quality requirements, along with the rapid expansion of the customers of the metal processing industry, metal cutting fluid The performance also been put forward new demands, mainly including the following aspects: the processing industry continues to expand the scope of metal cutting fluid market is mainly concentrated in the automobile manufacturing, aerospace manufacturing, medical equipment and medical equipment manufacturing. In recent years, the steel industry, home appliance manufacturing and mining equipment manufacturing industries have sprung up everywhere, more detailed requirements for metal cutting fluid, harsh and specialization. Processing materials and processing technology diversified now, endless kinds of new materials, innovative processing technology. The diversification of the materials, means that the material processing difficulty varies, the need to adapt to the difficulty of the range is increased, and nonferrous metals and alloys are increasingly being used to enhance the protective properties of the material surface, also called metal cutting fluids. Meanwhile, the processing technology is no longer a single, more and more combinations, disposable shaping craft growing tendency to put forward higher requirements, and adaptability of metalworking fluids. The increasingly high machining accuracy, surface quality requirements for the accuracy and surface finish of the workpiece, with more and more demanding requirements, the service life of the tool, the rejection rate of the products of the metal cutting fluid new challenges. Reduce overall operating and maintenance costs in the metal processing industry, customers for the cost of the metal cutting fluid control are becoming increasingly strict. Customer requires metal cutting fluid performance, stability, reduce downtime, workpiece rework, to extend the use of oil and tool life, thereby reducing their overall operating costs. Green, environmental protection, energy saving ideas intensifying as China's economic development, resource issues become increasingly prominent, and constantly enhance people's awareness of environmental protection, green concept is gaining in popularity. More and more customers require metal cutting fluid manufacturers to provide products to meet health and environmental requirements. Selected according to the characteristics of a number of different processing materials, different processes, different processing conditions ...... all of which affect the choice of cutting fluid. How to select the most suitable cutting fluid processing is a problem that must be given attention in the metal processing. Cutting fluid can generally be divided into water-based cutting fluids and oil-based cutting fluids. Oil-based cutting fluid is relatively higher prices, the overall performance is superior. For expensive machine or the workpiece surface quality requirements, generally used in oil-based cutting fluid. While the main processing requirements of efficiency and cost, you can choose to use a water-based cutting fluids. Secondly, the characteristics of the machine itself, also affect the choice of cutting fluid. Typically, the machine tool manufacturers in the design of the machine, taking into account the use of cutting fluids, so they recommend some brands of cutting fluid for their own equipment, such as some of the open machine oil cutting fluid can not be used to prevent large number of cutting oil evaporation and dissipation. In addition, a different tool and the workpiece material, because of their respective heat resistance, hardness, cutting different index, for the selection of the cutting fluid also of the same. Different processing methods, such as turning, milling, drilling, broaching, grinding, cutting fluid requirements. Solution times the performance of Flowserve Flowserve Corporation has long been a number of high-tech products to China, for example ECOCUTMIKROPLUS20 PLANTOCUTSERIES, ECOCOOLS71B ECOCOOL2506S, ECOCOOLSYN7045, ECOCUT7520LE-S, etc.. Dry machining emerging, due to its inherent heat generated in the process is difficult to be taken away, and the chip is more difficult to discharge, a greater impact on the life of the tool and other shortcomings, MQL will become metalworking trend. MQL Flowserve China will launch a special ECOCUTMIKROPLUS20 this product, the product with the equipment, minimal dosage. To achieve the same processing results and processing the number of cases, compared to the traditionally used oily cutting oil, the amount of the product is only 4 to 8%, the processing efficiency is high, can significantly reduce the processing time after processing tool, workpiece, chips are kept dry, the chip does not need treatment can be recycled, greatly reducing the cost of waste disposal, and the product has excellent extreme pressure be applied to almost any harsh processing, such as the crankshaft deep hole drilling (5 ~~ 7mm in diameter, depth of 80 to 107mm), another example reaming of the cylinder head, its excellent lubricating properties to ensure the machining accuracy of the workpiece, while reducing tool wear and extend tool life, has a number of well-known enterprises in the automotive industry With the success case. Flowserve particularly developed a series of maintenance-free products, such as ECOCOOL600NBFC, ECOCOOL700NBFC, ECOCOOL3015GSWNC, ECOCOOL2030S and so on. In most cases, metalworking fluids recycling, product stability and routine maintenance of the quality of its processing performance, strong the Flowserve biological stability, and therefore can do no rust sterile, thus long service life of the product, without late additives, and no downtime maintenance, to improve production efficiency, reduce maintenance costs, and help reduce production costs. The previously described ECOCUTMIKROPLUS20 is one of the outstanding representatives. In environmental protection, Flowserve more positive action everywhere rushed to take practical actions to reflect the importance of environmental protection. Back in 1976 developed the first patented low-pollution lubricants; 1979, Fox has begun a total ban on use of nitrite and ammonium nitrite products

Public financial construction of super lightweight foam concrete characteristics

1, saving energy source environmental protection foam concrete raw materials for cement, unlike polystyrene plastic extrusion plate, such as energy as raw material, and can use large amount of industrial waste residue.Cement production, although there are energy, but compared to the polystyrene foam and other organic insulation material production has been reduced a lot.In addition, foam concrete using inorganic materials as the main body, production without harmful substances produced, the production site without peculiar smell.In the application process will not produce decomposition, green environmental protection.The raw material of foaming agent for neutral, benzene, formaldehyde and other harmful substances, avoiding environmental pollution and fire hazard.From the perspective of green architecture, also should be the best choice for building insulation.2, lightweight foam concrete density, density grade is 300-1800kg/m3, commonly used in the foam concrete density rating of 300-1200kg/m3, in recent years, density of 160kg/m3 ultra light foam concrete in construction engineering was applied.As the foam concrete density, in both inside and outside the building, floor, wall, column dimensions in building structures such as the materials, the general can make the structure weight is reduced by about 25%, some up to structure weight 30%-40%.The foam concrete wall and roof materials in reducing the self weight of buildings at the same time, to increase the floor height, realize the construction of high-rise, thereby saving building area.At the same time, it can reduce the pressure on the ground buildings, reducing the building foundation, beam, column structure, can save building materials and engineering cost, greatly reduce the engineering amount, shorten time limit for a project, have remarkable economic benefits.3, good insulation properties as the foam concrete containing large closed small pores, so it has good thermal performance, namely, good insulation performance, which is not possessed by common concrete.Usually dry bulk density is 400 ～ 700kg/m3 foam concrete its thermal conductivity is usually 0.09 ～ 0.17W/ (m · K),

insulation for clay brick for 7 times, 10 times that of ordinary concrete.Practice has proved, in the northern regions of China 20cm thick foam concrete wall, the insulation effect and 49cm clay brick wall quite.Under the same heating condition, foam concrete building indoor temperature than the traditional clay brick houses can be increased by 5 ℃.In hot regions, and can greatly reduce the summer air conditioning starting frequency, to reduce electricity consumption, can effectively reduce the cost of living.Foamed concrete is our country at present all kinds of wall materials, without adding other insulating material or air layer, can achieve energy saving 65% preferred the new energy-saving wall materials.Table 1-1 foam concrete and several commonly used building material heat conductivity comparison.4, good fireproof performance of foam concrete cement as main material, inorganic material, in order to fully burning material.Fire resistance limit greater than 2h, can reach a standard.So it has good fire resistance,

 in buildings, can improve the fireproof performance.Another advantage is, we have R & D cast-in-place concrete foam insulation wall of steel structure, can be completely coated in the foam concrete, the steel structure protection, even fire, steel structure deformation is not easy to collapse, this also to a certain extent, solve the problems of steel structure fire protection, can play a double the role of fire.5, seismic performance foundation load is small, the seismic force is more powerful.Foundation load and wall materials wall materials directly related to density, density is small, the foundation of the building load is smaller, because, wall material weight to account for building 70% weight.

Steel production and installation of anti-corrosion fire prevention knowledge

Structure of the production process flow


(1) the mechanical index: steel structure indexes including the yield point, tensile strength, elongation, impact toughness.These indicators should be consistent with the "code for design of steel structure" requirement, but the low temperature impact toughness of structure may be in only in low temperature environment to test work.The mechanical indexes determination shall be in accordance with the "steel mechanical and technical performance test sampling rules" (GB2975-82)


(2): steel steel composition and processability, toughness, durability and other relevant.Which is the main content of carbon, alloy element content and sulfur, phosphorus and other trace elements content restrictions shall meet the specification requirements (GB222-84).


(3): process performance process performance include solderability and processing properties.Weldability and carbon content and carbon equivalent (low alloy steel), available solderability test identification.Processing performance through cold bending test to determine.According to (GB232-88) as the standard.


(4): deviation of the geometric size of steel (steel, steel, round steel, steel) dimensions and theoretical size deviation must be within the allowable range.Allowable deviation value may refer to national standard GB709-88, GB706-88, GB787-88, GB978-88, GB707-88, GB816-87 etc..


(5) steel shape blemish: steel surface shall be bubble, crack, crack, wrinkle, scar, mixed and pressed into the iron oxide.These defects must be removed, after the removal of the dent depth shall not be greater than the thickness of steel negative deviation.In addition, when the steel surface rust, pitting or scratches and other defects, its depth shall not be greater than the thickness of the steel negative deviation of 1/2 value.


(6) mechanical cutting: the use of mechanical force (shear, sawing, cutting, grinding) corresponding mechanical cutting plate machine, sawing machine, grinding wheel machine, is suitable for thickness of 12 ~ 16mm plate or profile of the linear cutting.


(7) cutting: the use of oxygen - acetylene, propane, liquefied petroleum gas flame heating to melt the metal, which uses compressed air to blow away erosion of metal liquid, so that the metal cut off, suitable for curve cutting and cutting.)


(8) plasma cutting: using plasma arc cutting flow, applied to stainless steel and other materials with high melting point cutting.


(9) hot forming processing: refers to the steel is heated to a certain temperature after further processing.This method is suitable for forming, bending and correction in room temperature can not do the workpiece.Thermal processing end temperature shall not be lower than 700 ℃.Heating temperature 200 ～ 300 ℃ steel have a blue brittleness, prohibited the hammering and bending.Carbon content beyond the low carbon steel's steel not general thermal processing.


(10): cold forming processing is performed at room temperature.Due to external force exceeds the yield strength of the material and the material to produce the required permanent deformation, or due to external force exceeds the ultimate strength of the material and portions of the materials according to the requirements and materials from the.Cold processing of all the materials hard and brittle tendency, which can make the steel through heat treatment in normal state or gouging out more serious edge portion of hardening.The ambient temperature is lower than -16 ℃ not cold working steel.Is lower than -12 ℃, and shall not process of low alloy steel.


(11) bending processing: according to the design requirements, the use of processing equipment and tooling plate or steel bent into a certain shape of the process.Cold bending for sheet, small steel; hot bending for thick plate and complex components, steel, hot bending temperature at 950 ～ 1100 ℃.


(12) coil processing: under the action of external force so that the flat plate of the outer fiber elongation, the inner layer of fiber shortening and deformation method.Coil coiling machine is completed by.According to the materials of different temperature, is divided into cold rolled and hot rolled.Coil for welding tube column, pipeline, air bag.


(13): the steel structure components of the hem edge bending at a certain angle or certain shape process called folding.Hems are generally used for thin plate.Edge folding machine used, with appropriate mould.


(14) molded: molded in pressure equipment using molds to make the steel molding method.Specific practice of blanking and forming, cutting, bending, roll round, drawing, rolling and other.


(15): shovel shovel edge edge is through to the shovel head hammer action and eradication of metal edge spare part and forming groove.Shovel edge there are manual and pneumatic parts, pneumatic tool with.Shovel edge precision is low, generally used for less demanding, a small groove processing.(


16) planing edge: edge planing workpiece is pressed, along the edge planer processing for reciprocating motion, planed groove.Edge planing planing straight edge or edges.(17): milling milling and planing edge similar, just the edge planer tool box tool and cutter of disk milling cutter for milling cutter in which replaced, along the edge of a straight line and also to make the rotary motion, the processing efficiency is high.


(18) carbon arc air gouging: carbon as electrode, and the planing metal arc heating a metal to a molten state, and then use compressed air to blow off of melted metal.High efficiency.


(19) the ground sampling method: in the assembly platform placed according to 1:1 component samples, then according to the position of the parts in the samples, were assembled into components.

Embodied in the steel production process

1, Steel plant units with no installation process, install components without order. If a hall, a building area of ​​6,000 square meters, a total of 4 layers. The members have all been installed to the ceiling, but the main steel columns are still not fixed welding small steel columns of the edge of the auxiliary have all welding finished. In another example, the steel columns installed as soon as possible the steel columns at the bottom of the pad pad flat weld it, then dense with fine stone. But some site color plate has begun to install the column foot has not closed.
Mishandling installation of the steel columns, like a candle, a root single plug up the day they can not form a solid framework unit, windy way, resulting in the collapse. Such security incidents occur several times, and should definitely be avoided.
3 anchor bolts uneven, the column feet plane without the prior measurement, embedded dislodged a column deviation, should be measured buried.
4 field welds generally not in place. Rigid connection pad welding gap is too small, not penetration results pad hand to pull it off; liner plate specifications do not meet the requirements, or even replaced with steel; the bad weld forming, rugged, and varies in width spatter, weld flash is not clear, bite the meat more stomata; the arc head arc tail without lead arc quenching board dishing and so on.
Steel company to install high-strength bolts, some more: Luya, even lower than the nut; bolts not tightened SHEAR Plum head not wring, the large hexagon no early wring final screw marked ; install the friction surface of the protective paper is not torn; high-strength bolts for temporary fixing, not lacquer sealed 48 hours after installation; without making torque and axial force re-examination, the tightening torque is calculated according to the specified; the friction coefficient trial is not in place, Some do, some do only one group. Rod bolts are not tightened, Rod is not straight, waist round hole is not big washers, caused by the nut base metal contact surface is too small, easily perforated.
 6 drawings reviewing carefully, resulting in the installation of quality defects. Such as design drawings did not indicate that drilling in the crane beam wing board, the construction unit has not argued, results welded mounting rails, causing the crane beam deflection. Violation of the mandatory provisions relating to crane beam does not allow flexible provisions.
7 the envelope color plate patchwork of tight close adverse side the nostrils "not plugging the impact against leakage of rainwater and beautiful. This article comes from the steel structure engineering network

Arc spraying anticorrosion technique in steel structure application

In today's society, as a systems engineering, is directly related to the safe operation and the service life of the steel structure of the anticorrosion engineering under engineering using method, design method and construction method and other aspects of attention.Practice has proved: strengthening steel structure fabrication and maintenance of anti-corrosion construction management and supervision for engineering use, side, the construction side and supervision side, it is quite important; in the steel structure design and production process, must have the professional anti-corrosion engineering and technical staff and experts involved or guidance.In recent years, arc spraying long-acting compound anticorrosion technology is gradually in steel production in the promotion and application of.

One, overview

Because the steel structure has good mechanical properties, bearing capacity of strong, easy manufacture, easy use in industrial production, construction and installation cycle is short, good sealing performance advantages, in the development of national economy, has been widely used in large span structures (bridges, for example, stadium house), light steel structure (large and medium-sized workshops), top building (New York World Trade Center and the Shanghai trade building etc.), shell (pressure vessel and pipeline).However, the steel structure in the service period, and it is the environment medium between prone to chemical, electrochemical and physical action, cause material modification and steel structure failure, it is often referred to as the corrosion of steel structures.

It has been recognized, the human use of steel structure is rarely due to the simple mechanical factors (such as tension, pressure, impact, fatigue, fracture and wear) or other physical factors (such as heat energy, light energy etc.) cause damage, most of the metal structure is destroyed and the surrounding environment factors.Therefore, the corrosion and corrosion protection of steel structures has become today's materials science, industrial and engineering fields can not be ignored important task, by the government and application in steel structures related to the attention of industries.

In two, long-term anti-corrosion steel structure engineering application necessity

So far, the steel structure corrosion problems are to world economy to bring huge loss.According to the developed country of a few industry statistics, each year as a result of steel structure corrosion caused economic loss accounted for about 2% of GDP in 4%.The United States in 1975 because of the economy loss caused by corrosion of approximately US $70000000000, accounting for about 4.2% of GDP in 1982, $126000000000; 1969 UK corrosion loss of 1365000000 pounds, accounted for 3.5% of GDP in 1976 in Japan; corrosion loss of $9200000000, accounting for 1.8% of GDP; according to our statistics in 1995, corrosion losses as high as 150000000000 yuan, accounting for about 4% of the gross national product.At present, around the world each year due to steel structure corrosion caused by the economic losses of hundreds of billions of dollars have been.

Moreover, the steel structure caused by corrosion accident endangering the safe operation of the structure.Corrosion cause of catastrophic accidents it is often seen., extremely serious consequences, especially for welding steel structure and under great stress of steel structure, because under the action of stress, corrosion will be greatly accelerated, namely so-called stress corrosion problems in steel structural damage, is very common.For example, the bridge structure or high roof truss structure because of the serious corrosion problems, must be reconstructed, otherwise, will cause serious consequences, of course, economic investment is quite large, now, the domestic construction of a large steel structure bridge, will cost to a few billion yuan.Japan 1970 to underground pipeline due to corrosion fracture, caused by gas explosion, 75 people were killed.In 1979 our country city of liquefied petroleum gas tank explosion casualties due to corrosion, dozens of people, the direct economic losses of 6300000 yuan.And, due to accidents caused by the shutdown, shutdown of indirect economic losses caused by, may exceed the direct economic loss of the number of times.

Because of this, the anticorrosive techniques of steel structures, especially long-term preservation new technologies using becomes and important.If a steel structure in 15 ～ 50 years of free maintenance, user can save a great amount of maintenance funds, and greatly improve the safety of steel structure and service life.

So far, from the steel structure project using method, design method and construction method and other aspects are still on the steel structure of the long-term preservation of the importance of the lack of sufficient attention, in the sense that still stays in the traditional anti-corrosion technology, the maintenance of later period may not follow.And, even if is the traditional anti-corrosion coating, because in the process of construction anti-corrosion construction technology is not good, often resulting in premature corrosion or damage of steel structure.For example, in 1965 March, the United States a gas pipeline for stress corrosion cracking on fire, causing the death of 17 people.Another example of a swimming pool early during the construction paint engineering construction technology of anticorrosion of steel structure, causing local premature corrosion, as shown in Figure 1, plus early roof system design of anticorrosion technology limitations of the times, makes the use of Party must be spent millions on the replacement or maintenance.

In addition, some projects also exist a larger problem, namely the implementation of the project before the special anti-corrosion engineering experts on steel structure anticorrosion technology assessment; engineering transfer, not to appoint a professional anti-corrosion construction engineer or specialist for the entire steel structure anticorrosion of strict quality testing; anticorrosive construction after the late sleep without any anxiety, periodic inspection and maintenance have no or reduced; regardless of the actual situation of anti-corrosion engineering costs, and construction units are combined with each other, thereby producing unqualified "bean curd dregs".

Various aspects of the problem, concentrated in the together time, the entire steel structure life is certainly doubtful, to date, there have been several accidents of steel structure, its direct consequences are disastrous, direct proof of the above analysis.

The steel structure anticorrosion project known as project of a system, it is because it relates to the steel structure engineering, engineering design, use, construction method and construction supervision and other aspects of the comprehensive factors.Only the aspects of reasonable combination and much attention, steel structure safety and the service life can be a reliable guarantee.