Industry news_News center_Shenzhou Baicheng Pipe Industry Co., Ltd. | The company mainly produces malleable cast iron fluid pipeline connections

What should be paid attention to in the maintenance of stainless steel elbows

What should be paid attention to in the maintenance of stainless steel elbows? There are many things to pay attention to when using and maintaining stainless steel elbows. Users need to use them in a certain way, and use and maintain them in an accurate and fair way. Notes are as follows: 1. Stainless steel elbows stored for a long time should be inspected regularly, and the exposed processing surfaces should be kept clean, cleaned of dirt, and neatly stored in a ventilated and dry place indoors. It is strictly forbidden to store them in the open air. Always keep the stainless steel elbow dry and ventilated, keep the device clean and tidy, and store it according to the accurate storage method. 2. When installing, the stainless steel elbow can be directly installed on the pipeline according to the connection method, and installed according to the position of use. Under normal circumstances, it can be installed at any position of the pipeline, but it needs to be checked for easy operation. Note that the medium flow direction of the cut-off stainless steel elbow should be from the bottom of the vertical valve disc to the upper flow, and the stainless steel elbow can only be installed horizontally. When installing stainless steel elbows, pay attention to the tightness to prevent leakage and affect the normal operation of the pipeline. 3. When the ball valve, globe valve and gate valve of stainless steel elbow are used, they are only fully open or fully closed, and are not allowed to be used to adjust the flow, so as to avoid erosion of the sealing surface and accelerated wear. There are inverted sealing devices in the gate valve and the upper threaded globe valve. The handwheel is turned to the upper position and tightened to prevent the medium from leaking from the packing. 4. Handwheel should be used for stainless steel elbow, please do not use lever or other tools to avoid damage to valve parts. Turn the handwheel clockwise to close, and vice versa to open. Ziah should be fair when using it, and ensure accurate use methods and means. 5. The bolts of the stainless steel elbow valve packing gland should be tightened evenly, and should not be pressed into a crooked state, so as to avoid bumps that hinder the movement of the valve stem or cause leakage. 6. The stainless steel elbow should always be kept clean during use, and the transmission thread must be lubricated on schedule. When a fault is found, it should be stopped immediately, and the cause should be identified to clear the fault.

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What is the allowable error of the standard wall thickness of malleable steel pipe fittings?

 Time of issue: 2015-09--28

Malleable cast iron pipe fittings are produced according to GB/T3287-2011 "Malgeable cast iron pipe fittings". The GB/T 3287-2011 standard is the second Chinese national standard set in July 2009. When the standard was revised, the international standard ISO49: 1994 "Moldable Iron Pipe Fittings with ISO 7-1 Thread" and the European Standard EN 10242: 1994/A2: 2003 "Malgeable Iron Threaded Pipe Fittings" were adopted, which are equivalent to the above two advanced foreign standards. 1. The mechanical properties of the pipe fittings are tensile strength ≥330MPa; elongation ≥8%, which is better than the malleable cast iron of the KTH300-06 grade specified in GB/T9440-2010 "Moldable Iron Castings". 2. The structural dimensions of the pipe fittings conform to the provisions of Appendix A in the GB/T3287-2011 standard, and are consistent with the dimensions stipulated in the ISO49:1994 and EN 10242:1994/A2:2003 standards. 3. The thread of the pipe fitting adopts GB/T7306.1-2000 "55° Sealing Pipe Thread Part 1: Cylindrical Internal Thread and Conical External Thread" and GB/T7306.2-2000 "55° Sealing Pipe Thread Part 2: Conical Internal Threads and Tapered External Threads". It corresponds to the European Community pipe thread standards EN10226-1: 2004 (E) and EN10226-2: 2005 (E). It is the same as the pipe thread profile, size, tolerance and code specified in the international standard ISO7-1:1994. According to the national standards collected at present, all major industrial countries in the world except the United States, the European Community and most countries in the world have adopted the pipe thread standards stipulated by ISO7-1. Therefore, the threads specified in GB/T7306 are consistent with international standards, and can also be smoothly matched with the pipe threads of most countries in the world. 4. The hot-dip galvanized layer of the pipe fittings conforms to the requirements of GB/T3287-2011, ISO49:1994, EN10242:1994/A2:2003 and other standards. The quality of the surface zinc layer is not less than 500g/m2, the average thickness is 70μm, and the average thickness of individual samples is not less than 450g/m2, and the average thickness is 63μm.

What are grooved fittings

 Time of issue: 2016-03--02

Grooved pipe fittings: Pipe fittings used when pipes are connected by grooves, see the attached drawings for details. Grooved pipe connection technology, also known as clamp connection technology, has become the first technology for liquid and gas pipeline connections. Although this technology was developed later in China than abroad, due to its advanced technology, it was quickly adopted by accepted by the market. From the beginning of research and development in 1998 to the present, after just a few years of development and application, it has gradually replaced the two traditional pipeline connection methods of flange and welding. Not only is the technology more mature, but also widely recognized by the market, and it has been actively guided by national laws and regulations. The application of grooved pipe connection technology makes the complex pipe connection process simple, fast and convenient. A big step forward in plumbing technology.

How to distinguish the authenticity of malleable steel pipe fittings

 Time of issue: 2013-11--15

Quick Identification Method of "One Knock, Two Look, Three Pounds" for Fake and Shoddy Pipe Fittings With the rapid development of my country's economy, the demand for malleable iron pipe fittings (commonly known as malleable steel pipe fittings) for water, gas and oil circuits is increasing day by day, and the quality requirements will also be higher and higher. The first thing to judge the quality of a malleable pipe fitting is to see whether it meets the corresponding national standards (GB/T3287-2000). However, some technical management, procurement and construction personnel suffer from little understanding of the national standards of malleable steel pipe fittings, and it is difficult to judge the quality of malleable steel pipe fittings for a while. They urgently need a more intuitive and portable atlas to help them identify. I believe that the publication of this atlas will help everyone to improve their ability to identify the quality of malleable steel pipe fittings and prevent them from being deceived. One knock: malleable iron pipe fittings are tough casting products. If knocked by external force, if the surface is dented or deformed a little, it will not crack, which means that its material performance is acceptable. Second look: When you look at the length of the thread, the thread length of general fake products always appears to be particularly short. Second, look at galvanizing. The galvanizing specified in GB/T3287-2000 refers to hot-dip galvanizing with better corrosion resistance. Zinc layer. The counterfeit and inferior products are treated with electro-galvanizing or other coatings after processing the thread. The surface of the thread has a zinc layer (coating), which is much lower in cost and has poor corrosion resistance. After being installed on the pipeline, yellow water (rust water) ) appears. Three: The malleable steel pipe fittings that cut corners will definitely reduce the outer diameter, reduce the wall thickness, and shorten the medium and long dimensions. It is generally more than 10% lighter than the pipe fittings that meet the national standard. We can judge fake and inferior by weighing the weight with our hands.

National standard of malleable steel pipe fittings

 Time of issue: 2013-12--03

Masteel is a common name for malleable cast iron. Current Standard: GB/T 3287-2000 Malleable Iron Pipe Connections Supersedes the following standards: GB/T 3287-1982|Technical conditions for malleable cast iron pipeline connections GB/T 3288-1982|Rules for acceptance of malleable cast iron pipeline connections GB/T 3289.1-191982 Malleable cast iron pipeline connection type and size pipe fittings structure dimension table GB/T 3289.2-191982 Malleable cast iron pipeline connection type and size elbow, inner and outer wire elbow GB/T 3289.3-1982 Malleable cast iron pipeline connection type and size 45° elbow 45° inner and outer wire elbow GB/T 3289.4-1982 Malleable cast iron pipeline connection type and size reducing elbow GB/T 3289.5-1982 Malleable cast iron pipeline connection type and size Reducing inner and outer wire elbows GB/T 3289.6-1982 Malleable cast iron pipeline connection type and size side hole elbow GB/T 3289.7-1982 Type and size of malleable cast iron pipeline connections, crescent bend, inner and outer wire crescent, outer wire crescent GB/T 3289.8-1982 Malleable cast iron pipeline connection type and size 45° crescent 45° inner and outer wire crescent 45° outer wire crescent GB/T 3289.9-1982 Malleable cast iron pipeline connection type and size U-shaped elbow GB/T 3289.10-1982 Malleable cast iron pipeline connection type and size tee, inner and outer wire tee GB/T 3289.11-1982 Malleable cast iron pipeline connection type and size Reducing inner and outer wire tee GB/T 3289.12-1982 Malleable cast iron pipeline connection type and size medium and large reducing tee GB/T 3289.13-1982 Malleable cast iron pipeline connection type and size side large reducing tee GB/T 3289.14-1982 Malleable cast iron pipeline connection type and size Small and medium reducing tee GB/T 3289.15-1982 Malleable cast iron pipeline connection type and size side small reducing tee GB/T 3289.16-1982 Malleable cast iron pipeline connection type and size Small and medium eccentric reducing tee GB/T 3289.17-1982 Malleable cast iron pipeline connection type and size 45° tee Y-type tee GB/T 3289.18-1982 Malleable cast iron pipeline connection type and size Y-type reducing tee GB/T 3289.19-1982 Malleable cast iron pipeline connection type and size side hole tee GB/T 3289.20-1982 Malleable cast iron pipeline connection type and size four-way GB/T 3289.21-1982 Malleable cast iron pipeline connection type and size reducing cross GB/T 3289.22-1982 Malleable cast iron pipeline connection type and size External joint Internal and external wire joint GB/T 3289.23-1982 Malleable cast iron pipeline connection type and size without square inner joint GB/T 3289.24-1982 Malleable cast iron pipeline connection type and size Reducer outer joint GB/T 3289.25-1982 Malleable cast iron pipeline connection type and size Eccentric reducer outer joint GB/T 3289.26-1982 Malleable cast iron pipeline connection type and size inner joint GB/T 3289.27-1982 Malleable cast iron pipeline connection type and size reducing inner joint GB/T 3289.28-1982 Malleable cast iron pipeline connection type and size internal and external screws GB/T 3289.29-1982 Malleable cast iron pipeline connection type and size through wire outer joint GB/T 3289.30-1982 Malleable cast iron pipeline connection type and size lock nut GB/T 3289.31-1982 Malleable cast iron pipeline connection type and size External square pipe plug GB/T 3289.32-1982 Type and dimension of malleable cast iron pipeline connections with side outside square pipe plug GB/T 3289.33-1982 Malleable cast iron pipeline connection type and size Inner square pipe plug GB/T 3289.34-1982 Malleable cast iron pipe connection type and size pipe cap GB/T 3289.35-1982 Malleable cast iron pipeline connection type and size Union elbow, inner and outer wire union elbow GB/T 3289.36-1982 Malleable cast iron pipeline connection type and size Union tee GB/T 3289.37-1982 Malleable iron pipeline connection type and size flat union GB/T 3289.38-1982 Malleable cast iron pipeline connection type and size tapered union GB/T 3289.39-1982 Malleable cast iron pipeline connection type and size flat union gasket

Classification and characteristics of grooved pipe fittings

 Time of issue: 2013-02--27

Reducing elbows have the best pressure resistance. However, due to various factors, the actual wall thickness of the floor heating pipe is usually 100%, and under this wall thickness, all kinds of pipes can meet the requirements of floor heating, and the pressure resistance advantage of the reducing elbow pipe cannot be reflected; thermal conductivity: use The pipes used for floor heating need to have good thermal conductivity, low temperature thermal shock resistance and low temperature shock resistance. First, the production standard of reducing elbow The current international standard for elbows is the American national standard ANSIB16.9 and 16.28. The standard outer diameter size range is 1/2 〃~ 80 〃, generally, seamless steel pipes are used as raw materials within 24 〃, and those from 26 〃 to 80 〃 are stamped with steel plates and then welded. The maximum wall thickness is 60mm and the minimum is 1.24mm. The most used steel grades are carbon steel (20#), alloy steel and stainless steel, with a total of 24 steel grades. The CrMo steel used in the boiler is like 15Cr, and the amount is relatively large. Tee, OD range from 2.5″-60″, from 26″-60″ for welding tee. Wall thickness 28-60mm. The size range of large and small heads, conventionally, we first talk about the big head size, then the small head size, the minimum size of the large head is 0.75 〃, the minimum size of the small head is 0.5 〃, the maximum size of the large head is 60 〃, the maximum size of the small head is 48 〃, 20-60 〃 is welded, and the wall thickness is 2.8 -4.5mm. 2. Processing technology of reducing elbow With the continuous development of the world economy and the continuous improvement of income levels, we aim to face the international advanced construction industry and shipbuilding industry and other related industries. Stamping elbows are mainly connected to pipe fittings. They can play an important role in the development of this product and set sail with world-class technology. The processing technology of stamping elbow pipe fittings has a certain process. In production, the production of reducing elbow can only be made of small diameter according to certain process technology. If the pipe size is too large, it is difficult to buy the finished reducing elbow. Use welded elbows. Because the welded elbow has more welds, the performance of all the elbows is not as good as that of the reducing elbow, and it is easy to be corroded and leaked. And because reducing elbows are produced in batches, the price is cheaper than welding elbows. Now there are precision casting elbows, which can be made of 316L, with better corrosion resistance. Since most of the pipe fittings are used for welding, in order to improve the welding quality, the ends are beveled, leaving a certain angle and with a certain edge. This requirement is also relatively strict, how thick the edge is, the angle and the deviation range. There are regulations. The surface quality and mechanical properties are basically the same as the tube. For the convenience of welding, the steel grade of the pipe fitting and the pipe to be connected is the same. The reducing elbow is made of malleable cast iron and is used for the connection of water supply pipes, water vapor pipes, gas pipes and oil pipelines. Specifications are 1/2-10 inches, and the products are widely used in pipeline installation, installation, and supporting services in petroleum, chemical, metallurgy, electric power and other industries. The test results of the reducing elbow and the push-pull elbow were used to detect the wall thickness of the outer arc, side arc and inner arc with a thickness gauge. The pushing speed is increased by 15mm per minute, and the curvature radius is increased by 50mm, that is, the pushing speed is accelerated, and the curvature radius is increased. The wear and tear of reducing elbows has always been a factor affecting safe and civilized production. With the continuous development of science and technology, materials have also continued to innovate, and materials such as cast stone, cast steel, alloy, and centrifugally cast composite ceramics have appeared one after another. Reducing elbows have corresponding development plans in the development of science, and are used in accordance with corresponding technical development and performance. Among them, the pipeline is lined with alumina ceramics with its high wear resistance, high hardness, good oxidation resistance, good corrosion resistance and extremely high performance. High resistance to high and low temperature strength, has become one of the most widely used wear-resistant materials, accounting for about 80% of the world's special ceramics market share (wear-resistant materials). 3. Advantages of the manufacturing process of reducing elbows 1. Reducing elbows are suitable for pipeline systems in petroleum, natural gas, chemical, hydropower, construction and boiler industries. 2. No tube blanks are needed as raw materials,