Prepare to install the required tools

One、Prepare to install the required tools

Cleaning and spinning firmware requires a variety of specific tools，In addition，In addition。

The following equipment should be prepared before installation:

>Calibrated torque wrenches, hydraulic screwdrivers, or other tightening tools;

>Steel wire brush, brass brush better；

>helmet

>Eye protector eyes

>lubricant

>Other factories specify tools, etc

Two、Steps for mounting the gasket

1.Steps for mounting the gasket

>Remove all foreign impurities and debris from gaskets, fasteners, nuts and gaskets；

>Check fasteners, nuts and gaskets for burrs, cracks and other defects；

>Check Integral Flange for warping, radial scratches, deep tool bumps, or other tightening tools；

>Check Blind Flange for warping, radial scratches, deep tool bumps, or other defects that affect proper seating of gaskets；

>If the defective parts are found, they should be replaced in time. If you have any questions about whether to replace them, you can contact the sealing manufacturer in time；

2.To justify the flange

>Align flange face and bolt hole

>Reports should be submitted in a timely manner in cases where no positive information is available

3.Install the gasket

>Make sure the gasket conforms to the specified size and material;

>Check the gasket to make sure there is no defect

>Carefully insert sealing gasket between two flanges

>Make sure the gasket is centered between the flanges

>Do not use the adhesive or anti - adhesive unless it is required in the gasket installation instructions

>Align the flange surface to ensure that the gasket is not punctured or scratched.

4.Lubricated bearing surface

>Only specified or approved lubricants are allowed in the lubricating bearing area;

>Apply enough lubricant to all threaded, nut and gasket forces

>Ensure that lubricant does not contaminate flange or gasket surfaces

5.Install and tighten bolts

>Always use the right tools

Use a calibrated torque wrench or other tightening tool that controls the function;

>Consult the technical department of the sealing manufacturer about torque requirements and regulations;

>Tighten the nut in accordance with the cross - symmetry principle;

Tighten the nut in the following 5 steps:

The first step:The initial tightening of all nuts is done by hand, the larger nuts can be assisted by a small manual wrench;

The second step:Tighten each nut approximately 30% of the total torque required;

The third step:Tighten each nut roughly 60% of the total torque required;

  Note:Large diameter flanges can be used more times for the above steps;

Step 5:Tighten all the nuts clockwise at least once to achieve all the required torque.

6.Tighten the bolt again

>Pay attention to:Consult the technical department of the sealing manufacturer for guidance and advice on retightening bolts;

>Non-asbestos gaskets and gaskets with rubber composition that have been used at high temperature shall not be tightened again (except as otherwise provided)

>The fasteners receiving the corrosion heat cycle need to be tightened again;

>The re-tightening should be done at ambient temperature and atmospheric pressure

Research on pipeline antiseptic coating

Abstract：Pipeline corrosion prevention is the key factor that affects the reliability and service life of pipeline system，Choose and use reasonable antiseptic coatings，It is of great importance to the safe operation, service life and economic cost reduction of pipelines.

In this paper, the causes of pipeline corrosion, the action of anticorrosive coating and the performance requirements are described,The development of pipeline anticorrosion coating was reviewed,The new development of pipeline anticorrosion coating technology is introduced,The application of these coatings in pipeline corrosion prevention is presented,The development prospect of pipeline antiseptic coating was also prospected.

Keywords:The pipe、corrosion、Anti-corrosion coating、Three-layer polyethylene、Double epoxy

One、preface

  Corrosion is the main cause of material failure，Metal corrosion is a major economic problem，According to relevant data statistics，The annual loss caused by metal corrosion in China accounts for about 5% of the national economy，Among them, pipeline corrosion accounts for a large proportion。With the continuous and rapid development of China's economy，The demand for energy is increasing，Pipeline construction is also increasing，The various kinds of gas supply, water supply and heat supply pipelines to be built in various urban planning are even more numerous，This makes pipeline antiseptic protection more and more important，This is directly related to the pipeline antiseptic performance and operating life。So，It is of great significance to strengthen the research on pipeline corrosion protection coating for the whole pipeline corrosion control。

Two、Research status of pipeline antiseptic coating

2.1Causes of pipeline corrosion

  Corrosion refers to the occurrence of chemical and electrochemical effects on the surface and environmental media of metal materials，Cause material degradation and damage。Corrosion of tubing is mainly caused by dissolved CO2, H2S, c1-a small amount of dissolved oxygen and bacteria in crude oil，These substances act directly on metals，Chemical corrosion。

  Chemical corrosion is not harmful，As a result, the surface of the steel pipe is convex，The main cause of perforation is electrochemical corrosion。When metals undergo an electrochemical reaction，Where the electrode potential is low, it is easy to lose electrons，As the anode；Where the electrode has high potential,As the cathode。In the case of O2 and H2O，Fe (OH) 2 hydrated iron oxide，That's corrosion。

2.2、Function and performance requirements of antiseptic coatings

1、The function of antiseptic coating

The anti-corrosion principle of the anti-corrosion layer is mainly to prevent corrosive media such as H2O, CL- and SO2 from infiltrating the metal surface of antiseptic coating，So as to prevent metal corrosion。The main function of pipeline antiseptic coating is as follows：1）Shielding effect 2）Corrosion inhibition 3）Sacrificial anode protection 4）Performance improvement

2.3、Development and application of anticorrosive coatings

  In 1865，Buried steel pipe when first put into use，There is no solution to the pipeline corrosion problem，Pipeline leaks occur frequently。For leak-proof reasons，Coal tar leaching and modified coal tar enamel are used as antiseptic materials.This material is oxidized when the temperature of the pipe rises,Volatile fraction,Causes brittle and peeling,Increase the cathodic protection current.

  The middle of the 20th century was a period of competitive development of various antiseptic materials.Paraffin, petroleum, asphalt and tape have been developed successively,Among them, tape antiseptic layer once occupied the dominant position.But the material is often stripped in corrosive soil,Shielding the cathodic protection current,Results in stress corrosion cracking.

  The antiseptic layer of double polyethylene structure appeared in the 1960s,Gradually changed the leading position of coal tar pitch.But with the continuous change of pipeline operating conditions,This kind of antiseptic coating gradually exposed the defects of easy damage, peeling, shielding cathodic protection current and so on.

  The Alaska pipeline came into operation in the 1970s,It marked the beginning of the application of dissolved epoxy powder coatings.Through continuous improvement of components and construction procedures,Dissolved epoxy powder became the most successful antiseptic coating in the 1980s,But its mechanical strength is not ideal.

  By the late 1990s,Dissolved epoxy powder and three layers of polyethylene two antiseptic coating gradually become the mainstream,In recent years, double layer epoxy has also gradually begun to be applied on a large scale.Currently abroad,There are two distinct views on the choice of antiseptic coatings:North America generally favors the FBE,Europe favours PE.U.S. statistics show that,The present antiseptic layer is the situation of FBE, PE and coal tar,The number and range of other early coatings are increasing and decreasing.

Three、Introduction of three-layer PE and two-layer FBE technology

3.1Three-layer polyethylene

In the 1980s the German company mannesmann invented a three-layer polyethylene called the "perfect coating"。The manufacturing process is to spray a layer of epoxy primer on the surface of the steel tube，The steel pipe is then fed into the coating zone at a certain rotation speed，The first extruder extruded a film of adhesive according to a certain thickness and density and wound it around the surface of the steel tube，When the adhesive is still melting，The second extruder extrudes polyethylene film and wraps it around the adhesive to form the coating。

The structure of three layers PE antiseptic layer is：The bottom layer is FBE,About 50 to 127 microns，The intermediate layer is copolymer glue，About 200 microns，The outer layer is polyethylene，About 3 mm。This structure will FBE high cohesiveness, oxygen resistance, resistance to chemical corrosion and cathodic disbonding performance and high density polyethylene moisture resistance, electrical insulation and mechanical damage of the resistance combined into an organic whole，It has the advantages of strong adhesion to the pipe surface, good electrical insulation performance, shock resistance and long service life，And the cathodic protection current density is small，Only 1 ~ 3 mu m/m2。

The service life of three-layer PE is expected to reach more than 40 years，But it's more expensive，At present, it is widely used in Europe，It's less used in the United States。Our country has been introduced since 1995，The main steel pipe plants have set up three layers of PE anti-corrosion production lines。A total of about 2000km of shaanxi - jing gas pipeline and ku-shan pipeline use three-layer PE，The coating was also used in the west-east gas pipeline project。

3.2Double epoxy

  The double epoxy was invented by OBRIEN，It combines the anti-corrosion property of single-layer FBE with the anti-mechanical damage property of surface plastic FBE，It is characterized by strong bond performance, high operating temperature, soil stress resistance, impact resistance and cathodic stripping resistance.The two-layer FBE is composed of two epoxy powders with different properties which are sprayed into a film at one time during the spraying process，The bottom epoxy coating is the same as the single FBE，To provide corrosion protection，The outer FBE is a plasticized epoxy powder layer，Mainly used to resist mechanical damage。The thickness of two layers is usually 525~1000，Suitable for all kinds of caliber pipe，It is also applicable to the antiseptic needs of the joints, elbow and special-shaped components。It is also applicable to the antiseptic needs of the joints, elbow and special-shaped components，Choose a different two-layer FBE structure type。Its shock resistance and cathodic protection current density are similar to those of three-layer PE，It is the only anticorrosion system that can be used in cathodic protection system and is completely compatible without shielding，Failure safety，So much more。

  The price of a double FBE varies according to its structure and thickness，But it is generally cheaper than three-layer PE，As the technology matures its cost is still falling。

  In our country，Jinshan yiyangzi pipeline, ningbo city gas official website, sinopec material equipment department pipeline and other projects have adopted double-layer FBE。Due to the excellent comprehensive performance and improving economy of double layer FBE,It is bound to be more widely used。

Four、Pipeline anticorrosion coating new technology

4.1Liquid polyurethane anticorrosive paint

  Polyurethane asphalt is a pipeline corrosion resistant layer with excellent performance since 1990s，The coating is a two-component thermal spray solvent-free system composed of polyols and isocyanate solutions。This antiseptic coating has superior performance，Simple construction，The antiseptic layer is of good quality，Strong impact resistance and flexibility，Microbiological corrosion resistance，Good scratch resistance, wear resistance and drag resistance，Have some toughness，Good anti - cathode stripping performance，Good chemical stability，Uv radiation，Life is long，Life is long，Cost-effective and environmentally friendly，It has obvious technical and economic advantages，Especially suitable for repairing damage, repairing mouth and old antiseptic layer，At present, it has become the main material for the international pipeline anti-corrosion layer repair，It has a wide range of applications and prospects。

4.2Inorganic nonmetallic antiseptic layer

Compared with organic coatings, inorganic non-metallic coatings have better corrosion resistance, aging resistance, temperature resistance and cold resistance，The service life is greatly improved，There are mainly ceramic coating, enamel coating and glass coating。

Ceramic coatings have high chemical stability，Corrosion, oxidation and high temperature resistance，At present, a variety of ceramic coating methods have been developed, such as self-propagating high temperature synthesis, thermal spraying and chemical reaction。Enamel coating has excellent corrosion resistance and can resist various concentrations of organic and inorganic acids,Various bases and salts,Comprehensive anti-corrosion performance is excellent.The glass coating has good compactness, corrosion resistance and abrasion resistance,A smooth surface,It can reduce drag,Its outstanding characteristic is:Advanced generation technology,Never aging, safe to use, excellent corrosion performance, wear resistance, good mobility, strong weather resistance, non-toxic, harmless pollution, low cost,Construction specifications,Wide range of USES.

Due to the great development prospect of inorganic anticorrosion technology,All countries in the world have taken inorganic non - metal composite anticorrosion pipeline as a key problem,More breakthroughs are expected.

4.3Nano - modified material coating

  The research indicated:The organic coating was modified by nano - technology,The comprehensive performance can be improved,Especially increase the mechanical strength, hardness and adhesion of materials,Improve light resistance, aging resistance, weather resistance, etc.By adding some nanoparticles with small particles in the material, the sealing property of the material can be increased to achieve better waterproof and anti-corrosion effect.

  For example, nano TiO2 particles have a scattering effect on ultraviolet rays. The addition of such nanomaterials can effectively enhance the anti-ultraviolet ability of the materials and significantly improve the anti-aging property;SiO2 nanoparticles have face serious lack of coordination, large specific surface area and the surface oxygen etc, make its showed strong activity, join the coating can make the coating strength, toughness and ductility increased significantly.For inorganic coating materials, such as nanometer structure, can also improve its plasticity and toughness.

  At present, some technologies of modification of anti-corrosion materials by nano technology have been patented, and such anti-corrosion materials have also appeared in the market.In general, however, the technology is still in its infancy and has great prospects for development.

Five.Conclusion

For a long time, the multi-layer composite coatings, such as three-layer PE and double-layer FBE, will occupy the mainstream position of pipeline anti-corrosion coatings.Improving the structure and process of three-layer PE and two-layer FBE, improving performance and reducing cost will also be an important research direction in the future.The liquid polyurethane anticorrosion coating will play an important role in the repair of the pipeline antiseptic coating such as repairing the damage, repairing the mouth and repairing the old antiseptic coating.But as the new material, new craft, new technology application and development of inorganic non-metallic anti-corrosion technology and nanometer technology will have great development and application prospect of pipeline anticorrosion technology will be perfected, pipeline construction will make greater achievement.

We produce Galvanized Threaded Elbow and Galvanized Socket Elbow,if you want to buy, please contact us!

Types of Welded Fittings

There are many different types of welded fittings. We offer all of the most varieties, including the following:

45°Welded Elbow

Reducing Elbow

Welded Flange Tee

Reducing Tee

Barred Tees

90 Elbow LR & SR

Cushion & Target

Coupling

Concentric Reducer

Eccentric Reducer

Stub End

Cap

180 Return Bend

3R & 5R Bends

Cross

Lateral

Reducing Lateral

Swage Nipple

Applications

Though they are very effective, welded pipe fittings can be costly because of the skilled labor they require. Therefore, they are usually only used in applications that require high performance. These applications include chemical and nuclear reactors, as well as shipbuilding.

Common knowledge of flanged pipe fittings: how to control the folding and cracking of aluminium flanges?

Aluminum alloy flange forgings are widely used for medium and high strength parts with certain requirements due to their advantages of small proportion, good thermal conductivity, high electrical conductivity and corrosion resistance. The process features of aluminium alloy forging heating is poor liquidity, low plasticity, good thermal conductivity, narrow forging temperature range, strict beginning, finish forging temperature, heating the performance characteristics of die forging is aluminum alloy does not produce with heterogeneous change, mainly rely on the correct control forging mechanical parameters to improve metal organization, uniform metal flow continuously along the forging shape distribution in order to improve the mechanical properties; The quality characteristics of hot die forging are that aluminum alloy is easy to produce two major quality defects of fold and crack.

Among them, folding can reduce the bearing area of parts, and it is easy to generate stress concentration during service and become a fatigue failure source, which is very harmful. The crack damage is greater, and the crack waste accounts for 5% ~ 10% of the total forging waste.

The reasons for the folding are the large cross-section size of the blank, unreasonable shape of the blank, the forming of local pressing type, the small radius of the circular Angle at the transition point of mold and bore, and the large amount of pressing at one time during operation.

Cracks are mainly caused by the obvious anisotropy of extruded aluminum bars, in which the longitudinal mechanical properties are significantly higher than the transverse mechanical properties (the longitudinal toughness is the largest while the transverse toughness is the smallest). At the beginning of finish forging ranging from three to stress or under the condition of the three-way under the action of compressive stress and maximum shear stress, easy contact between billet grain damage, is not conducive to the development of the slip deformation, deformation ability is poor and oblique crack generation.

At the same time caused by uneven deformation of additional stress and thermal stress produced by the uneven temperature, deformation of large parts and small deformation of interaction, tensile stress cracking occurs beyond the part strength.

Aluminium alloy forging in the actual production of folding and crack defects in quality control, should be prevention first, technology and production management, the combination of specific should do the following several aspects:

(1) the necessary analysis should be made on the technical conditions of the forging equipment, technological equipment and blank, so as to make the forging process in line with the production reality and achieve advanced, reasonable, complete and accurate results.

(2) in the forging die design, should consider forging the forming force and equipment tonnage required, reasonable distribution of blocking or intermediate billet size, choose the right way of packing, increasing the die mould chamber transition radius or draft Angle, the lower mold chamber (including flash bridge) of the surface roughness value.

(3) the aluminum alloy used shall be ensured free from defects such as folding, cracking and coarse crystal rings. For the heating of billets, the amount of charging should be strictly controlled, and the billets should be turned over within half of heating time, so as to minimize the time from discharging to forging.

(4) in the forging operation, should be based on the principles of the operation of the first light after heavy, properly control the deformation degree of blank or hammer force, reasonable use of extruding the anisotropy of raw materials, preheating forging die and operating tools correctly, and reasonable lubrication forging die (especially the upper die die chamber).

(5) in forging production, the production monitor unified command, first article inspection shall be competent technical personnel to cooperate, work instruction of shift production when necessary, at the same time, the first production of the first article, should be as much as possible to arrange in day shift production, to detect the quality of forgings defects, after confirmation no folding and defects such as cracks, but within the prescribed time interval with rhythm, the uniform and balanced production.

(6) forging test, you must do first article inspection, strictly implement the "three inspection system", but should also do process inspection tour, intermediate inspection, inspection and final inspection, prevent systemic defects into the next process.

Analyze plastic coated pipeline and 3PE anti-corrosion pipeline

Plastic coated pipe with 3 PE anticorrosion pipeline looks very similar, at first glance like the same kind, even in the industry also has a lot of silly points not clear, there are often customers call advisory, since these two pipes are inspecting &controlling, so, what is the difference between them? It's time to find out.

Description of coated pipe

Plastic coated pipe, also known as plastic coated steel pipe, steel plastic composite pipe, plastic coated composite pipe, is based on steel pipe, PE(modified polyethylene) for hot dip plastic or EP(epoxy resin) as the main anti-corrosion materials. PE antiseptic layer is fused on the inner surface of steel tube (bottom tube) or EP antiseptic layer is fused on the inner surface of steel tube (bottom tube) by spray, roll, dip and suction process. The coated steel pipe has excellent corrosion resistance. At the same time, the coating itself also has good electrical insulation, will not produce electrical corrosion. Low water absorption, high mechanical strength, low friction coefficient, can achieve long-term use. It can also effectively prevent the damage of plant root system and soil environmental stress.

Plastic coated pipe advantages

1. Adapt to buried ground and moist environment, and can withstand high temperature and extremely low temperature.

2. Strong anti-interference ability. If the coated steel pipe serves as the cable sleeve, it can effectively shield the external signal interference.

3. Good pressure strength and maximum pressure up to 6Mpa.

4. Good insulation performance, as the protection pipe of the wire will never leak electricity.

5. No burrs, smooth pipe wall, suitable for wire or cable during construction.

Application field of plastic coating pipeline

1. Various forms of circulating water system (civil circulating water, industrial circulating water), with excellent performance and anti-corrosion life up to 50 years.

2. Fire water supply system.

3. Water supply and drainage transportation of all buildings (especially for cold and hot water systems in hotels, hotels and high-end residential areas).

4. Various chemical fluid transportation (the product is acid, alkali and salt resistant).

5. Buried pipes and crossing pipes of electric wires and cables.

6. Ventilation pipes, supply pipes and drainage pipes of mines and mines.

7. Municipal sewage pipeline.

3PE anti-corrosion pipeline

3 PE anticorrosive coating steel pipe refers to the three layer structure of polyolefin (MAPEC) anti-corrosion steel pipe, parent metal include seamless steel pipe, spiral steel pipe and straight seam steel pipe, its good corrosion resistance, resistance to moisture permeability and mechanical properties, etc., has been widely used in industrial pipeline. It is a kind of antiseptic pipeline commonly used in China. There are also IPN8710, FBE epoxy powder, epoxy coal tar asphalt and other anti-corrosion methods. Generally refers to the steel pipe outside the wall corrosion. An anti-corrosion layer of 3PE anti-corrosion steel pipe is of vital importance to the life of buried pipelines. Some pipes of the same material are buried in the ground for decades without corrosion, and some of them will leak out in a few years. It's because they use different outer coatings.

Advantages of 3PE anti-corrosion pipeline

For 3 PE anticorrosion pipe USES a lot of people are just a man who knows one second, ordinary steel in the conditions of use cases, can appear serious corrosion, which will reduce the lifespan of the steel tube, 3 PE anticorrosive steel pipe service life is long, generally is 30 to 50 years or so may be used. Long running or can save more resources, significantly lower energy costs, and also has the stronger ability of water resistant and corrosion resistant, and also do not need to attached pipe trench, can be directly buried underground or in the water, on the construction is simple rapid, comprehensive cost is low, under the condition of low temperature and has good corrosion resistance and impact resistance, and in a certain environment can directly buried permafrost.

Use of 3PE antiseptic pipeline

The function of 3PE anti-corrosion pipeline is really extensive, which is applicable to underground coal mine supply and drainage, downhole grouting, positive and negative pressure ventilation, gas drainage, fire sprinkler and other pipe networks. Waste residue and return water transportation pipeline of process water in thermal power plant. It has excellent applicability to water supply pipeline of spray - proof and sprinkler system. Power, communication, highway and other cable protection sleeve. Suitable for high - rise building water supply, heat network heating, tap water engineering, gas transmission, underground water transmission and other pipelines. Petroleum transport pipeline, chemical pharmaceutical, printing and dyeing industries such as the transmission of corrosive media of the process pipeline. Sewage disposal pipe, sewage pipe and biological tank anti-corrosion engineering. Agricultural irrigation pipe, deep well pipe, drainage pipe network and so on use, say 3 PE anticorrosive steel pipe in the current construction is indispensable, and believe that through the extension of science and technology, it still has more brilliant achievements in the future.

Finally, small make up teach you a simple identification method, plastic coated pipe that look very smooth, and the method of 3 PE pipe due to steel tube outer wrapping a layer of anti-corrosion polyethylene tape, appearance looks like a line of interface.

We produce all kind of pipe fitting, including Galvanized Threaded Elbow,Stainless Steel Stub End.

Superior alloy steel bend Services Helping Technologies Advance

While we marvel at the incredible achievements that digital technologies have generated, we can not ignore these accomplishments would not have been possible without the finest processes generating them. Using tubes and sticks in complicated assemblies enables Pipe Fitting Manufacturer to execute chip manufacturing which will be put in a selection of everyday products and electronic equipment we all rely on.

Superior tube manufacturing processes permit you to procure the tubing and alloy steel bend flex to specifications which fit into your current equipment. There are a selection of tube bending procedures to pick from based on which you need in materials and design configurations. It is possible to choose from ram-type bending, roll bending, compression bending, and rotary draw bending.

Hardness testing

Hardness is the ability of a material to resist being pressed into its surface by harder objects. According to different test method and the range, the hardness can be divided into brinell and vickers hardness, rockwell hardness, micro vickers hardness and so on many kinds, different units have different test methods, suitable for different characteristics of materials or occasion.

Characteristics of the test：

Hardness testing is one of the important indexes for testing material properties and one of the fastest and most economical testing methods. The hardness test can reflect the differences in chemical composition, structure and processing technology of materials. It is often used as a means of supervision in all walks of life. In steel material, for example, when martensite formation, due to the integration of the supersaturated carbon atoms increases the lattice distortion, and increases the dislocation density, which significantly reduces the plastic deformation ability, this is why martensite with high hardness. Obviously the greater the higher the degree of distortion, the carbon content is also the higher hardness, different carbon content of steel after quenching, hardness value and martensite dimension and its carbon content in a wide range of good corresponding relationship between, hardened steel after tempering hardness depends on the tempering temperature and holding time. The higher the tempering temperature, the longer the insulation time, the lower the hardness. Therefore, hardness test can be used to study the steel phase change and as a means to detect the heat treatment effect of steel.

The test method：Plastic rockwell

The test principle of：

During the specified loading time, a constant initial load was applied to the steel ball above the tested material, followed by the main load, which was then restored to the same initial load. The measurement results are the total depth of the steel ball into the material, minus the elastic recovery within the specified time after unloading the main load and the pressure depth caused by the initial load.Terms and definitionsEach minute of the rockwell hardness scale indicates that the head moves vertically by 0.002mm. Rockwell hardness value is calculated from the following equation:HR = 130-0.002 - / - eHR - rockwell hardness numberE - pressure depth after main load removal

Metallic Brinell

The test principle of

Test force is applied to the hard alloy ball of a certain diameter to press into the surface of the sample. After the specified holding time, the test force is removed and the diameter of the indentation on the surface of the sample is measured. Brinell hardness is proportional to the test force divided by the quotient of indentation surface area. Indentation is regarded as a sphere with a certain radius which is one half of the diameter of the head ball.

Metal Vickers

The test principle of

Test force is applied to the diamond pressing head of normal tetrahedron with specified angles on the top two opposite surfacesIn addition to the test force, measurement of the surface indentation diagonal line length. Vickers hardness number is the quotient of the test force divided by the surface area of indentation, indentation is consideredIs an ideal shape with a square base surface and the same Angle as the head.

Roughness

Influence of roughness and solutionsAs we know, brinell hardness is measured with a desktop super constant temperature water bath, the pressure head is the steel ball head, in a certain amount of pressure into the surface to be tested by a circular indentation, with a reading microscope to measure the diameter of the circular indentation, then find the appropriate in the brinell hardness scale of hardness value, namely the hardness value of tested samples, and the roughness of the surface being measured directly affect the accuracy of hardness measurements. When the measured surface roughness value is greater than the Ra = 0.8 mu m, with the increase of roughness, the smaller the measured surface resistance of pressure head, the plastic deformation is large, circular indentation is large, the corresponding hardness value is small, the measurement value is lower than its true value. The test shows that the measurement deviation is above 10HB

Solution: when measuring the hardness of samples, we must pay attention to the test conditions for whether the surface roughness under test is consistent. Under the condition of normal use, must ensure that the sample of the measured surface roughness values less than or equal to the Ra = 0.8 mu m, if the sample of the measured surface roughness values greater than Ra = 0.8 mu m, can be by mechanical method (grinding) or manual method, cutting down the surface to be measured, the sample of the measured surface roughness to test conditions. The effect of roughness is minimized so that we can obtain the accurate measurement value. 

Common Applications and Uses for Long Radius Elbows

Additionally, these kinds of 90° long radius elbow are utilized dependent on the fluid or material that is passing through the uterus, gases and a few fluids demand less immunity, which is offered by a very long elbow. Other benefits include:

The pressure fall within the tube is not as striking when long distance elbows are utilized. This is great for gas pipelines, in addition to food and drink piping.

Ever since less immunity is made, long elbows decrease the danger of copies or clogs.

Still, there are a number of cases in which 180° short radius elbow are favored. For example, in regions that have space constraints, short elbows may be utilized to modify the management of a pipeline. Furthermore, short radius elbows are typically less expensive than long radius elbows, and that, sometimes, may be a determining factor.

Elbows are Made from all sizes, plus they are used in Many Different pipeline systems, such as chemical and industrial facilities, oil and gas, pipes and water, and food and drink applications.

32 questions to be clear about NDT!（二）

10. How many kinds of near display methods can ultrasonic flaw detector be divided into?

(1) the horizontal coordinates of type A display wave display screen represent the time (or distance) of ultrasonic transmission and broadcast, and the vertical coordinates represent the height of reflected echo.

(2) the horizontal coordinates of the type B display oscillograph screen represent the time (or distance) of ultrasonic transmission and broadcasting, and such display results in the section diagram of the probe scanning to check the depth direction;

(3) the waveform display screen of type C display instrument represents the projection surface of the workpiece under inspection, which can draw the horizontal projection position of the defect, but cannot give the buried depth of the defect.

11. What is the main function of ultrasonic probe?

1. The probe is an electro-acoustic transducer that converts the returned sound waves into electrical pulses.

2, control the transmission of ultrasonic wave direction and energy concentration degree, when change the spread of the ultrasonic probe Angle or Angle, can make the sound waves of the main internal energy according to different Angle into the medium or change the sound directivity, improve resolution;

3. Realize wave-type conversion;

4. Control working frequency; Applicable to different working conditions.

12. Why do we need to strengthen the recording and reporting of ultrasonic testing?

Any workpiece after ultrasonic testing, must be out according to the surveyor's report as the work quality of certificate, a correct inspection report, in addition to establish a reliable detection methods and results, to a large extent depends on the original record and finally according to the inspection report is very important, if we check the artifacts do not make record nor the report, so there's no point inspection to check.

13. What are the applications of NDT?

Application time: design stage; Manufacturing process; Inspection of finished products; In-service inspection.Application: all kinds of materials (metal, non-metal, etc.); Various workpieces (welding, forging, casting, etc.); Various projects (road construction, dam construction, bridge construction, airport construction, etc.).

14. What are the types of defects in the weld in ultrasonic testing? How are they classified?

In the ultrasonic inspection of welding seam, the defects in welding seam are generally divided into three categories: spot defect, line defect and surface defect.A defect less than 10mm in length is called a point defect in the classification. Generally unmeasured length, the defects less than 10mm shall be counted as 5mm. A defect longer than 10mm is called a linear defect. A defect greater than 10mm in length and greater than 3mm in height is called a surface defect

15. The function of superdetector and its main application industry

Super finder is a portable industrial non-destructive testing instrument, it can be quick and easy, no damage, accurately artifact within a variety of defects (weld, crack, inclusion, folding, porosity, sand holes, etc.) in the detection, location, evaluation and diagnosis. It can be used in both laboratory and engineering field. The instrument can be widely used in the manufacturing, iron and steel metallurgy, metal processing industry, chemical industry and so on need to defect detection, and quality control, is widely used in aerospace, railway transportation, boiler, pressure vessel, etc in service in the field of safety inspection and evaluation of the life. It is a necessary instrument for nondestructive testing industry

16. National and industrial standards for ultrasonic testing

National and industry standards for ultrasonic testing include:

1. QB/T 12604.1-90 nondestructive testing terms ultrasonic testing

2. General technical conditions of JB/T 10061-1999 type A pulse reflection ultrasonic detector

3. JJG 746-91 ultrasonic flaw detector national metrological verification regulation of the People's Republic of China

Welded Pipe Manufacturing Process

Welded Pipes are made from Plate or proceeds Coil or strips. To produce welded pipe, initial coil or plate is wrapped in the circular part with the assistance of plate bending equipment or from a roller in the instance of lasts procedure. When the round section is wrapped from the plate, the tube could be welded or without filler material. Welded pipe could be fabricated in large size with no upper limit. Welded pipe using filler material may be utilized in the production of 180° long radius elbow and Welded Elbow. Welded pipes are more economical compared to seamless pipe and Weak as a Result of weld

There are various welding techniques used to weld the pipe.

HFW- High-frequency welding

SAW- Submerged Arc Welding (Extended seam & Spiral Seam)

32 questions to be clear about NDT!

1.What is NDT/NDT?

(1) non-destructive testing is a test method to check the surface and internal quality of the inspected parts without damaging the workpiece or raw materials.

(2) NondestructiveTesting: NondestructiveTesting (NDT)

2.What are the commonly used methods of detection?

According to the research and analysis of NASA, nondestructive testing methods can be divided into six categories and about 70 types. However, in practical application, the following kinds are common:

Conventional nondestructive testing methods include:

- Ultrasonic Testing (UT);

- Radiographic Testing (RT);

- Magnetic particle Testing (MT);

- Penetrant Testing (PT);

- Eddy current Testing (ET);

Unconventional nondestructive testing techniques include:

- Acoustic Emission (AE);

- Leak Testing (UT);

- Optical Holography Holography;

- Infrared Thermography of thermal imaging;

- Microwave detection Testing

3.What is the basic principle of ultrasonic inspection?

There are many kinds of ultrasonic testing equipment, but in the actual testing process, pulse reflection ultrasonic testing equipment is the most widely used. Generally in homogeneous material, the existence of defects will cause material discontinuity, the discontinuous and acoustic impedance caused by inconsistencies, often by reflection theorem, we know that ultrasonic wave in two different acoustic impedance of the medium of the boundary surface reflection will occur with the size of the reflected energy and acoustic impedance difference on both sides of the interface between media and the size of the interface orientation,. The pulse reflection ultrasonic flaw detector is designed according to this principle.

At present most of the portable pulse reflection type ultrasonic flaw detector are A scanning mode, namely so-called A scan display mode display is the abscissa of the ultrasonic propagation time in tested materials or propagation distance, ordinate is ultrasonic reflection wave amplitude. , for example, there is a defect in a steel workpiece, as a result of the existence of the defect, the defect and steel materials formed between a different medium, the interface between the interface between the acoustic impedance is different, after the launch of ultrasonic wave in the interface, the reflection occurs (see figure 1), and was accepted by the probe to the reflected energy, abscissa in the display screen of a certain position will be displayed a reflected wave waveform, the abscissa of depth in this position is the defects in the tested materials. The height and shape of the reflected wave vary from defect to defect, reflecting the nature of defect.

4.What are the advantages of ultrasonic testing compared with X-ray testing?

Ultrasonic testing has the advantages of high sensitivity, short period, low cost, flexibility, high efficiency and no harm to human body. The disadvantage is that the work surface needs to be smooth, requiring experienced inspectors to identify the types of defects, and there is no direct perception of defects. Ultrasonic testing is suitable for testing thick parts.

5.What are the main features of ultrasonic testing?

(1) when the ultrasonic wave propagation in a medium, has the character of reflection on the different quality, and the interface, such as defects, defect is equal to or greater than the size of the ultrasonic wave length, the ultrasonic reflected on defects, flaw detector reflection wave can be displayed; If the size of the defect is even smaller than the wavelength, sound waves will bypass the radiation and cannot be reflected.

(2) the wave sound has good directionality, the higher the frequency, the better the directionality. It radiates to the medium with a narrow beam, which is easy to determine the location of defects.

(3) the transmission energy of ultrasonic wave is large, for example, the energy transmitted by the ultrasonic wave with a frequency of 1MHZ (100hz) is equivalent to one million times of the sound wave with the same amplitude and a frequency of 1000HZ (Hertz).

6.What may be the cause of the disappearance of the bottom wave when the ultrasonic inspection is carried out?

(1) major defects in the near watch;

(2) absorption defect; 

(3) major tilt defects;

(4) the oxide coating is not well combined with the steel plate.

7.What are the three principles for selecting K value of ultrasonic testing probe?

(1) sound beam scan the entire weld section;

(2) the sound beam should be perpendicular to the main defect as far as possible;

(3) sufficient sensitivity.

8.What are the three cases of defects identified in the jb1150-73 standard?

(1) multiple reflected waves with no bottom waves but defects.

(2) there are only a number of disordered defect waves without bottom waves.

(3) both defect waves and bottom waves exist simultaneously.

9.The distance specified in jb1150-73 - what is the purpose of the amplitude curve?

Distance -- amplitude curve is mainly used to determine the size of defects, which provides a basis for acceptance criteria.

Scrap line -- the maximum allowable equivalent of defect determination;

Quantitative line -- the control line that determines the size and length of defects;Testing line - detection starting sensitivity control line.

Stainless steel pipe and stainless steel elbow use different

Stainless Steel Pipe Fitting China comprise flange elbows, but in addition, there are specific sales flanges, in addition, there are specific sales elbow. In reality, the ideal method is to blend these. Is the selling of this Street. Specializing in the creation of large scale flange factories, but additionally elbows, tees, and pipes. Pipe fittings are components that link pipes to plumbing. Made of the identical material as the tube.

Stainless Steel elbows are utilized where pipelines are switched; flanges are utilized to connect pipes into plumbing; they're attached to pipe finishes; tee pipes are utilized where three pipes have been constructed; and four pipes are utilized where four pipes are constructed; Reducers are used where two pipes of different diameters are attached.

Stainless Steel elbow setup on site is very handy. The elbow is controlled and utilized based on a specific way and principle throughout use and connection, and contains great installation attributes and worth, and it has to be utilised in a specific way constantly.

Stainless Steel Elbow China are utilized and promoted in various areas and industries to guarantee the security and pollution-free water quality. They're employed in various areas and play a significant part. Outstanding mechanical and physical attributes.

How well do you know your flanges?

Bear in mind that flanges come in many different sizes and shapes to suit unique applications. 

Threaded Flange: Much like the slip-on, this flange slips across the pipe but is famous since it can be attached with no welding because it's made with tapered threads to operate with pipes which have outside threads. Also low price, it is good for smaller pipes and extremely combustible places where welding is hazardous. They are widely utilized in programs where the juncture doesn't come in contact with the gas or fluid making them and they're also valuable in software keeping down costs when exotic metals are utilized.

Welding Neck Flange: Frequently used for high-pressure software to decrease the concentration of anxiety, this kind of flange includes a neck that's welded to the bottom of pipes.

Blind Flange: This flange can be used to seal the conclusion of pipes methods and protect against flow, which makes it effortless to run pressure tests. They're not hard to work around because they permit easy access to plumbing.

Stainless steel elbows enhance bending performance

The elbow of stainless steel relates to the field of architectural decoration. The main technical points are: including the elbow body, the elbow body of the product includes curved curved sections and straight sections respectively connected at both ends of the curved section, and also includes curved bending resistance. The two ends of the curved section of the product are connected through anti-bending sections, and the two are hollowed out. Through the arrangement of the anti-bending portion, the bending resistance of the elbow body is enhanced, thereby increasing the service life of the elbow body.

Stainless steel pipe fittings are a kind of pipe fittings. It is made of stainless steel material so it is called stainless steel pipe fittings. It contains: stainless steel elbow, stainless steel tee, stainless steel four-pass, stainless steel reducer, stainless steel cap and so on.

Two-phase stainless steel elbow pipe is provided with a lining. The inner lining is partially inside the nozzle, and is fixedly connected with the inner wall of the wide mouth. The other part of the lining is outside the nozzle, and the product is outside the nozzle. Cutaway cuts are provided. When the stainless steel elbow is connected with the stainless steel pipe, it is easy to be installed by butt joints to eliminate the tension generated by the pipe connection and has strong anti-deformation ability. After welding, no deformation occurs at the joint after installation, and the installation effect is very good.

WH-STEEL CO.,LTD. Against welding elbow advantage

Big butt is big butt welding elbow: welded elbow is steel hot-pressing molding or bend forging forming, its connection form is directly to the elbow and the steel pipe butt welding, butt welding elbow generally main manufacturing standards GB/T12459, GB/T13401, ASME B16.9, SH3408, SH3409, HG/T21635, HG/T21631, SY/T0510. The butt welding elbow usually has a 45 degree bend, 90 degree bend, 180 degree bend etc., the material has carbon steel, alloy steel and stainless steel.

Its main use is: large caliber butt welding elbow is mainly used to connect two different end radius of the pipe, or for pipe diameter modification. This type of elbow typically need according to the specific project requirements or detailed drawings for production, in addition to meet the requirements of the pipe size must also consider the pipe, such as pipeline pressure, fluid viscosity, abrasion resistance, corrosion resistance, fluid conveying a variety of factors such as temperature. The welding elbow is usually welded at the pipeline construction site, which is due to the different welding standards of various kinds of pipelines, which requires on-site welding according to the pipeline weld grade.

Large diameter welded elbow according to bend Angle, has 45 ° butt welding elbow, elbow and 180 ° 90 ° butt weld ends butt welding elbow, elbow other special Angle, can generally figure processing customized according to customer. General materials of large-caliber butt welded pipe fittings include: carbon steel, alloy steel and stainless steel elbow. The elbow can be divided into long radius butt welding elbow and short radius butt welding elbow according to its radius of curvature. The radius of curvature of the long radius to the welded elbow is 1.5 times the outer diameter of the pipe, that is, R= 1.5d. The radius of curvature of the short radius to the welded elbow is equal to the outside diameter of the pipe, which is R=1D. Where D is the diameter of butt welding elbow and R is the radius of curvature. According to the pressure level, there are about 17 kinds of pipes, which are the same as the American pipe standard, including: Sch5s, Sch10s, Sch10, Sch20, Sch30, Sch40s, STD, Sch40, Sch60, Sch80s and XS. Sch80, Sch100, Sch120, Sch140, Sch160, XXS, the two most commonly used are STD and XS

Our factory is specialized in welding elbow. Wh-steel CO.,LTD. Historically, no matter what industry, is all there is more, words shop around, and compared under the condition of increasingly fierce, if butt welding elbow company want to occupy the domestic market and the rapid development of a place, must be through the function of universal commodity itself to competitiveness. So why is WH-STEEL CO.,LTD (large-caliber welding elbow) the leading position in the industry?Welding elbow to ensure long - term effective and safe operation of equipment and product quality. More and more production equipment, especially chemical production equipment, are made of stainless steel of different materials. Production of all kinds of stainless steel grades in China more and more, but because of improper material selection, improper welding technology, component assembly is not reasonable, also can lead to shorten the operation time, even failure and safety accidents. In order to ensure the safety of the operators, it is necessary to analyze the causes of stainless steel elbow leakage failure. It is necessary for researchers to analyze and study the leakage accident of stainless steel elbow in chemical production equipment. Macroscopic examination based on the failure parts, parts material determination of chemical composition, metallographic microscopic inspection, corrosion area detecting data based on the analysis of system, find out the cause of the failure accident.

WH - STEEL CO., LTD in the first half of the review exhibition information

In order to expand the market, WH-STEEL CO.,LTD participated in four exhibitions in the first half of the year , respectively, 8th NORTH AFRICA PETROLEUM EXHIBITION & CONFERENCE; The 18th China International Petroleum & Petrochemical Technology and Equipment Exhibition; Tube & Wire Dusseldorf 2018; 23rd INTERNATIONAL OIL & GAS and Petrochemical Exhibition, Iran, Tehran.

The exhibitions in the first half of this year involved Algeria, Germany, Iran and other relevant countries. Not only improved the WH - STEEL CO., LTD in pipe fittings industry reputation and professional degrees, but also promote the communication between countries, such as Algeria's international oil and gas show, not only during the exhibition, bustling, but also attracted the attention in Algeria - department of local government long, detailed ask WH - STEEL CO., LTD production process and testing products, and on the local news home page.

Many important clients have also been gained in these exhibitions, for example：French WIT SAL INC, Algeria's Oil & Gas company, the Gates of the United States, Wyman-Gordon， Wison Offshore & Marine Limited, WONILT & ICO.,LTD, STOCK SERVICES，S.S.E PIPEFITTINGS LTD，ALLIED INTERNATIONAL UK LTD，NERO PIPELINE CONNECTIONS，LONDON FITTINGS & FLANGES LTD，etc.

Looking forward to the second half of the year, WH-STEEL CO.,LTD has decided to participate 2018 the 26th kazakh international oil and gas exhibition and2018 the 8th China international pipe material exhibition（Tube China）

We are Carbon steel Cap Exporter and Carbon Steel Reducer Exporter,if you are Interested in our product,please contact us!

Knowledge of forgings is extensive

Made of round steel or steel ingot die forging forming after machined pipe fittings, it is the connection form of Socket weld (Socket Welding - SW), within the insert pipe Socket Socket Welding, therefore, is known as the "pipe", mainly for ANSI/ASME B16.11, manufacturing standard, GB/T 14383-2008.

1.Threaded elbow of socket elbow

The socket elbow is a kind of high pressure elbow pipe connection fitting which is mainly formed by forging blank of round steel or ingot mould and then shaped by lathe machine. Is forged socket series fitting to a common standard for socket bend are standard GB/T14383, GB/T14383, American standard ASME B16.11, standard SH3410 petrochemical, chemical standard HG/T21634 according to the pattern is divided into 90 ° and 45 ° elbow socket socket bend, in accordance with relevant provisions of the common standard, socket of the specifications of the elbow has DN6, DN8, DN10, DN15, 3/4 ", DN25, DN32, DN40, (, DN65, DN80, DN100. The commonly used order specification is DN15~DN50. By pressure grade: 3000LB, 6000LB, 9000LB or SCH80, SCH160, XXS.

 Mainly applied to petrochemical industry, medicine and health care, electric power, spaceflight, war industry, fire protection, metallurgy, shipbuilding, gas, nuclear power, and the environmental protection requirements under pressure is high, the size precision and other departments and fields.

2.Socket tee threaded tee tee

The socket tee is a kind of high pressure pipe connection fitting which is mainly formed by forging blank of round steel or ingot and then shaped by lathe machine. Is one of the forged socket series fitting socket tee standards commonly used standard GB/T14383, GB/T14383, American standard ASME B16.11, standard SH3410 petrochemical, chemical standard HG/T21634 according to pattern is divided into 90 ° and 45 ° elbow socket socket bend, in accordance with relevant provisions of the common standard, socket of the specifications of the elbow has DN6, DN8, DN10, DN15, 3/4 ", DN25, DN32, DN40, (, DN65, DN80, DN100. By pressure grade: 3000LB, 6000LB, 9000LB or SCH80, SCH160, XXS.

Mainly applied to petrochemical industry, medicine and health care, electric power, spaceflight, war industry, fire protection, metallurgy, shipbuilding, gas, nuclear power, and the environmental protection requirements under pressure is high, the size precision and other departments and fields.               

3.Y type tee

Type Y three-way four-way, mainly by round steel or ingot mould forging blank forming, and then by the lathe machine processing the forming of a high pressure elbow pipe connection accessories. Is forging a standard socket series pipe fittings have standard GB/T14383, GB/T14383, American standard ASME B16.11, standard SH3410 petrochemical, chemical standard HG/T21634 according to the pattern is divided into 90 ° and 45 ° elbow socket socket bend, in accordance with relevant provisions of the common standard, socket of the specifications of the elbow has DN6, DN8, DN10, DN15, 3/4 ", DN25, DN32, DN40, (, DN65, DN80, DN100. By pressure grade: 3000LB, 6000LB, 9000LB or SCH80, SCH160, XXS.

4.Socket collar screw collar

Hoop - pinyin guan gu, coupling, is a commonly used accessory in industrial pipe connections. A pipe hoop is a short tube used to connect two pipes. Also called the external joint. Because of its convenient use, pipe hoop is widely used in civil construction, industry, agriculture and other fields. The main manufacturing standards of hoops are GB/T14383, ASME B16.11 and BS 3799.Socket pipe band made of round steel or steel ingot die forging forming after machining of the pipes, it is the connection form of Socket weld (Socket Welding - SW), within the insert pipe Socket Socket Welding, therefore, referred to as "Socket pipe hoop", mainly for making standard ANSI/ASME B16.11, GB/T 14383.The types of socket collar include double socket head and single socket head. Among them, the double socket pipe hoop can be divided into equal diameter and different diameter, and the double socket pipe hoop with different diameter can be divided into concentric and eccentricity.The socket collar consists of a socket, socket, socket slot, etc. Its features lie in that there is a socket slot on the socket, and the socket,The socket is located at both ends of the bending part. Compared with the existing technology, the design is reasonable, the operation is simple, the practicability is strong, enhances the operation quality and the convenience.Socket collar can be widely used in pipes of different caliber, including single pass, three pass, four pass, water meter and valve. Due to the use of socket structure, the pipe joint reduces the cost, installation, use and maintenance very convenient, and has a high leak-proof capacity.

5．Pipe cap

Other names of pipe cap include head closure, head closure, cover head, pipe cover and head closure. Pipecap connection can be divided into socket and screw threads. The socket cap is welded to the end of the pipe, or the pipe fitting is installed on the outside thread of the pipe end to cover the pipe fitting. Both are used to close the pipe line and function as a plug. The production standard is GB/T14383 ASME B16.11

Congratulations to wh-steel CO.,LTD for adding new bending equipment and 50% off of bending products

In order to promote the development of productivity, improve product quality and better serve consumers, WH STEEL CO.,LTD added large-scale pipe bending equipment in May 2018.

The addition of new equipment is of great significance to WH-STEEL CO.,LTD. Secondly, the new pipe bending equipment improves the original production standard of the bending pipe in the factory, making the product more green and environment-friendly. Third, make the data more accurate, reduce the errors in the production process, and improve the quality of products; Fourth, the production process was accelerated and the production cycle was shortened.

In the suitable operation period, in order to give back to the vast number of customers, any bending products can enjoy a 50% discount, welcome new and old customers to purchase.

The bending pipe of our company can be produced from small to large. Including all kinds of pipe bending: 12 cr1mov bend, a 180 - degree bend, 12 crmo bend, 12 crmov high bending tube, 15 crmo bend, 16 MNR bend, 12 15 crmog crmog bend, bend, Q345A bend, Q345B bend, 12 cr1mov alloy bend, 12 12 cr2mog cr2mov bend, bend, A335P1 bend, 30 crmoa A420WPL6 bend, bend, 10 crmo910 bend, A335P1 bend, A335P11 bend, A3 35P12 bend pipe, A335P22 bend pipe, A335P5 bend pipe, A335P9 bend pipe, 20MnMo bend pipe, 0Cr13 bend pipe, P9 bend pipe, WP5 bend pipe, WP11 bend pipe and WPL6 bend pipe can be divided into: WCB (carbon steel), LCB (low temperature carbon steel), LC3 (3.5% nickel steel), WC5 (1.25% 0.5% chrome molybdenum steel), WC9 chromium (2.25%), C5 (% 5% chromium molybdenum), C12 molybdenum chromium (9% 1%), CA6NM (4 (12% chromium steel), CA15 (4) (12% chromium), CF8M stainless steel (316), CF8C stainless steel (347), CF8 stainless steel (304), CF3 (304 l stainless steel), CF3M (316 l stainless steel), CN7M (alloy), (monel), N7M M35-1 (Hastings nickel alloy B), CW6M(Hastings nickel alloy C).

The add new equipment, believe that will be WH - STEEL CO., LTD in 2018, with new breakthroughs in the production, improve product efficiency and improve product quality, bring clients more and more high quality pipe fitting products. , WH - STEEL CO., LTD are Forge Fitting Manufacturer and Pipe Fitting Manufacturer, said an official with the new equipment put into production, increase the confidence of factory production, focus on the high-end product development research, for the factory improve the quality of products provides a good condition, strengthens the production line of informationization, intellectualized, believes that the application of new equipment, will brings to the factory, the company's customers more long-term interests.