If the re inspection results are unqualified (including the items whose preliminary inspection results are unqualified and re inspection is not allowed), the supplier can submit them for acceptance one by one; Or re conduct heat treatment (the number of RE heat treatment shall not exceed times), and propose acceptance with a new batch.Cold drawn or cold rolled precision square tube (gb-) is a cold drawn or cold rolled precision square tube with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision square mechanical structure or hydraulic equipment can greatly save machining hours improve material rate and improve product quality.Holy rose,× × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × ～ × × Standard treatment of steps for preventing oxidation of ~ square tube square tube is a kind of metallic maintenance. The main components are iron and zinc. It is easy to have redox reaction in the air. Once the reaction occurs, and the original characteristics have changed. However, in order to maintain the original relevant characteristics, anti-oxidation treatment is required. The direct reason is to prevent the square tube from reacting with the oxygen in the air which is the way to isolate the oxygen in the air. Today, this article makes a relatively standardized treatment on the relevant steps to prevent oxidation of square tubes: the key depends on what kind of antirust paint you use. . If you use epoxy zinc rich or iron rich antirust paint,Holy roseHot dip galvanized square pipe welding, you can directly spray fluorocarbon paint on it; if alkyd antirust or red lead is used, it shall be cleaned with paint remover and sprayed with epoxy zinc rich or iron rich antirust paint again before fluorocarbon paint can be sprayed.Oil drilling pipe (yb-) is a square pipe used for internal or external thickening at both ends of oil drilling. Steel pipes are divided into turning wire and non turning wire. Turning wire pipe is connected with joint and non turning wire pipe is connected with tool joint by butt welding.Louisville,Hot dip galvanized square tube is a kind of square tube which is welded after using steel plate or steel strip to curl and form, and on the basis of this square tube, the square tube is placed in the hot dip galvanized pool and formed through a series of chemical reactions; The production process of hot-dip galvanized square pipe is relatively simple, but the production efficiency is very high and there are many specifications and varieties, but this kind of square pipe needs little equipment and capital, which is more suitable for the production of small galvanized square pipe manufacturers.The pipeline is only subject to chemical pickling, rust and old coating. Sometimes it can be used as the reprocessing after sand blasting. Although chemical cleaning can make the surface reach a certain cleanliness and roughness, its anchor lines are shallow and easy to pollute the surrounding environment. The square tube shall be submitted for acceptance in batches, and the batch rules shall comply with the provisions of corresponding product standards.Strength QB square strength refers to the performance of metal materials under static load (excessive plastic deformation or fracture). Since the action modes of load include tension, compression, bending and shear, the strength is also divided into tensile strength, compressive strength, flexural strength and shear strength. There is often a certain between various strengths. Generally, tensile strength is used as the basic strength indicator. Precision pipe is a seamless pipe with high dimensional accuracy and good surface finish for mechanical structure and hydraulic equipment. The selection of precision seamless mechanical structure or hydraulic equipment can greatly save machining hours, improve material rate and improve product quality. Seamless pipe is rolled in the annular pass composed of variable cross-section circular hole groove and fixed conical plug. Cold drawing is usually carried out on single chain or double chain cold drawing machine. This method is to put the heated pipe blank in a closed cylinder and the perforated rod and rod move to extrude the part from the smaller die hole. This method can produce steel pipe with smaller diameter.

Square tube nonferrous metals, also known as non-ferrous metals, refer to metals and alloys other than ferrous metals, such as copper, lead, zinc, aluminum, brass, bronze, chromium,Holy roseCold galvanized square pipe factory, nickel, manganese, molybdenum, cobalt square tube, vanadium, tungsten,Holy rose400X400 square tube, titanium, etc. are also used in industry. These metals are mainly used as alloy additives to improve the performance of metals. Tungsten, square tube titanium, molybdenum, etc. are mostly used to produce cemented carbide for tools. The above non-ferrous metals are called industrial metals. In addition, there are precious metals: platinum, gold, silver and rare metals, including radioactive square tubes.Whether the bottom is galvanized or painted; For paint, according to the standard of iso, you can protect the indoor and outdoor environment for years, which is not a big problem.Structural stainless steel square pipe (gbt-) is a hot-rolled (extruded, expanded) and cold drawn (rolled) square pipe made of stainless steel for corrosion-resistant pipes, structural parts and parts widely used in chemical, petroleum, light textile, food, machinery and other industries.Job description,Strength refers to the performance of metal materials under static load (excessive plastic deformation or fracture). Since the action modes of load include tension, compression, bending and shear, the strength is also divided into tensile strength, compressive strength, flexural strength and shear strength. There is often a certain between various strengths. Generally, tensile strength is used as the basic strength indicator. Appropriate sites and warehouses shall be selected. The sites or warehouses for storing steel pipes shall be in clean and unobstructed places, away from factories and mines that produce harmful gas or dust. Weeds and sundries shall be removed on the site to keep the steel pipe clean; In the warehouse, alkali, salt, cement and other materials that are corrosive to the steel pipe. Different types of steel pipes shall be stacked separately to prevent confusion and corrosion; Large section steel rail, steel plate, large-diameter steel pipe, forging, etc. can be stacked in the open air; Small and medium-sized section steel, wire rod, reinforcement, steel wire and steel wire rope can be stored in a well ventilated shed, but they must be covered and padded; Some small steel pipes, steel sheets, steel strips, silicon steel sheets, that is and generally adopts ordinary closed warehouse all kinds of cold-rolled and cold drawn steel pipes and high and corrosive metal products can be stored in the warehouse; The warehouse shall be selected according to geographical conditions, the warehouse with roof, enclosure, tight doors and windows and ventilation devices; The warehouse is required to pay attention to ventilation in sunny days, close and damp proof in rainy days, and often maintain a suitable storage environment. The principle of reasonable stacking and first in first stacking is to stack according to varieties and specifications under the condition of stable stacking and ensuring safety. Materials of different varieties shall be stacked separately to prevent confusion and mutual corrosion; It is forbidden to store articles that have corrosive effect on steel pipes near the stacking position; The bottom of the stack shall be padded high, firm and flat to prevent the material from moisture or deformation; The same kind of materials shall be stacked according to the warehousing order, first out; The section steel stacked in the open air must be provided with wooden mats or strip stones. The stacking surface is slightly inclined to facilitate drainage. Pay attention to the straightness of the material placement to prevent bending and deformation; The stacking height shall not exceed m for manual operation, m for mechanical operation, and m for stacking width; A fixed channel shall be reserved between stacks, generally .m, and the access channel is generally ~ om depending on the size of materials and transportation machinery; The bottom of the stack shall be padded up. If the warehouse is cement floor, it can be padded up by .M; If it is muddy ground, it must be padded . ~ .m high. If it is an open site, the cement ground shall be padded with O & middot; ～O· m, . ~ . m higher than the sand and mud surface, the angle steel and channel steel shall be stacked in the open air, i.e. the mouth shall face down, and the I-beam shall be placed vertically. The i-groove surface of the steel pipe shall not face up to avoid ponding and rust. The packaging and protective layer of the protective materials shall be coated with agent or other plating and packaging before leaving the factory, which is an important measure to prevent material corrosion. Attention shall be paid to protection during transportation, loading and unloading and shall not be damaged The storage period of materials can be extended, the warehouse shall be kept clean and the maintenance of materials shall be strengthened. Before warehousing, materials shall be prevented from being drenched or mixed with impurities. Materials that have been drenched or contaminated shall be wiped according to their properties, such as steel wire brush for high hardness and cloth, cotton and other materials for low hardness; The materials shall be regularly after warehousing. If there is corrosion, the corrosion layer shall be removed; Generally, the steel pipe surface does not need to be coated with oil after being cleaned, but for high-quality steel, alloy steel sheet, thin-walled pipe, alloy steel pipe, etc., the internal and external surfaces need to be coated with anti rust oil before storage; Steel pipes with serious corrosion shall not be kept for a long time after rust removal and shall be used as soon as possible. With the development of economy, all kinds of square tubes, rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes have been recognized by the majority of customers for a long time. There are more and more counterfeit products on the market. In order to prevent being deceived when you are in square tubes, you need to know some knowledge about how to judge the authenticity of square tubes: & ldquo; We can judge by observing the surface and flatness of the square tube. If the surface of the square tube is relatively flat, it can reflect that the square tube is good. On the contrary, if the surface is not goodB. converter steel: (a) acid converter steel; (b) Basic converter steel. Or (a) bottom blown converter steel; (b) Side blown converter steel; (c) Top blown converter steel.Stage ( & mdash; )

Because the green billet can be pressed into any shape, it is easy to weld the square tube into difficult products.Administration,Main uses of square tube: square tube is mainly used in tap water engineering, petrochemical industry, chemical industry, electric power industry, agricultural irrigation and urban construction. It is one of the key products developed.After the process of polishing, the surface effect of the square tube is quite good. The quality of the polishing process directly affects the external image of the square tube. Therefore, we must choose the appropriate polishing according to the above, and pay more attention to the polishing process of the square tube.Square pipe for conveying flammable and non flammable fluids, Standard No.: gbt (gbt - ). The representative material is l-l pipeline steel. It is mainly used to transport flammable and non flammable fluids. Low pressure or high pressure square pipes have high requirements. The purpose of large-diameter qb square pipe is qb square pipe, C-shaped steel and H-shaped steel. It is mainly used in the construction of simple plant, steel structure and other infrastructure. Qb square pipe is generally used as the frame and purlin of the plant. C-shaped steel Steel is an important support for the plant, and H-section steel is used as load-bearing. Especially in recent years, the time is slow, the work progress is affected, and the investment is large. For some small and medium-sized enterprises, if the investment in the plant is too high, the capital will be produced after operation Serious impact. The plant built with qb square tube, C-section steel and H-section steel has the characteristics of time saving, money saving and fast use. Therefore, the sales of qb square tube, C-section steel and H-section steel have increased significantly in recent years and become the first choice for plant construction. Qb square tube, C-section steel and H-section steel are mainly used in the construction of simple plant, steel structure and other infrastructure The qb square tube is used as the frame and purlin of the plant. The C-shaped steel is used as the important support of the plant, and the H-shaped steel is used as the load-bearing. Especially in recent years, a large number of small and medium-sized enterprises around the country have started to build spacious and bright plants. If the traditional buildings are built, the time is slow, the work progress is affected and the investment is large. For some small and medium-sized enterprises Said that if the investment in the plant is too high, it will have a serious impact on the capital after operation. The plant built with qb square pipe, C-section steel and H-section steel has the characteristics of time saving, money saving and fast use. Therefore, the sales of qb square pipe, C-section steel and H-section steel have increased significantly in recent years, becoming the first choice for plant construction. Large diameter qb square pipe plant is introduced Shao measures for effective wrinkle of seamless square pipe: check the wrinkle state, even when the wrinkle around the part is determined to be less than the clamping force, and the gradual increase of the roll gap force can be. When drawing the cone and hemispherical components, it should be increased to increase the inner diameter of the inner plate and the tensile stress of the wrinkle drawbead. Adopt the principle of loosening after tightening to loosen after tightening and ask Question.Holy rose,Principle of cold drawing strengthening: the lattice defects of steel increase during plastic deformation, and the serious distortion of defect lattice will hinder the progress and slip of lattice, so the yield point of steel increases and the plasticity and toughness decrease. Due to the internal stress in plastic deformation, the modulus of steel decreases. The cold drawn reinforcement is stored at room temperature for ~ d or heated to ~ ℃ and maintained for a fixed time. This process is called aging treatment.Welding is a synthetic gradient material, which can be used as solder to weld special-shaped materials in order to overcome the mismatch of chemical, mechanical and physical properties between base metals.Brinell hardness (HB), Rockwell hardness (HRC) and Vickers hardness (HV) are commonly used.