The inspection items, sampling quantity, sampling position and test of square tube shall be in accordance with the provisions of corresponding product standards. With the consent of the demander, hot-rolled square tubes can be sampled in batches according to the rolled root array.The pipeline is only subject to chemical pickling, which can remove oxide scale, 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.Phoenix,Square pipe, also known as square and rectangular cold-formed hollow section steel, is referred to as square pipe and rectangular pipe for short. The allowable deviation of wall thickness of square pipe is f and J qb respectively. When the wall thickness is no more than mm, it shall not exceed plus or minus % of the nominal wall thickness. Long term square pipe, seamless square pipe, galvanized pipe, old brand price advantage and quality guarantee! When the wall thickness is greater than mm, it is plus or minus % of the wall thickness, except for the wall thickness of corners and weld areas.Hot dip galvanized square pipe is widely used, mainly in curtain wall, solar power generation support, construction, machinery and steel structure engineering, especially in curtain wall, machinery and construction. The effect of cold galvanized square tube is far from that of hot galvanized square tube; How to distinguish hot galvanized square pipe from cold galvanized square pipe?Louis Trichardt,Viewing color: the color of the cold galvanized square tube is yellowish green, cyan white or slightly colored at a fixed angle with the sun. The color of hot-dip galvanized square pipe is silver white at a fixed angle with the sun.In this period, the technology of continuous rolling pipe was not mature.The second is to clean the surface of the opposite pipe. When cleaning the opposite pipe, the surface should be cleaned with solvent or emulsion. Square pipes of various specifications, square rectangular pipes, seamless square pipes, galvanized square pipes, galvanized pipes are supplied in time and cost-effective. They have become the preferred brand of many wire products. Welcome to buy! It is used to remove oil and dust. It is only suitable for removing grease and dust on the surface of square pipe, which can not remove rust and oxide scale. Therefore it can only be used as an auxiliary means in production.

With the progress of the times and the faster and faster economic development, the places where large-diameter seamless square tubes are used are becoming more and more popularAfter aluminum deoxidation in molten steel, & omega; When (ALS) is .% ~ .%, calcium treatment can achieve better effect on the denaturation of Al.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.Affordable price,The characteristics of square pipe are as follows: the production process of square pipe is simple, the production efficiency is high, the cost is low and the development is fast. The strength of spiral square pipe is generally higher than that of straight seam square pipe. It can produce square pipe with larger pipe diameter with narrow blank, and square pipe with different pipe diameter with blank of the same width. However, the weld length is increased by ~, which will be oriented to the whole country for a long time Individuals and enterprises provide all kinds of square tubes, square rectangular tubes seamless square tubes, galvanized square tubes, galvanized tubes, on-site settlement, honest operation, local offices, long-term cooperation, and low production speed. Therefore, most of the smaller square tubes adopt straight seam welding, and most of the large-diameter square tubes adopt spiral welding.In recent years, large-diameter seamless square tube plays a good role in economic development. Because there are many types of large-diameter seamless square tubes, the continuous casting process of large-diameter seamless square tubes is also different. What are the specific steps of the continuous casting process of large-diameter seamless square tube? As the name suggests, square tube is a kind of square tube type. Many materials can form square tube body. Its medium is used for what purpose and where it is used. Most square tubes are steel tubes, which are unpacked, leveled, crimped and welded to form round tubes, Then the round pipe is rolled into a square pipe, and then cut into the required length. Generally, square tubes per package are mostly in large specifications in terms of spot, and . - ~~ - square tubes are divided into structural square tubes, decorative square tubes, building square tubes, etc. according to their uses.When the vehicle is replaced with seamless square tube blank, the material is too soft to affect the requirements, so as to ensure the quality of parts and avoid wrinkles.

Section shape classification square tubes are classified according to section shape: simple section square tubes & mdash& mdash; Square tube, rectangular tube and complex section square tube & mdash& mdash; Surface treatment classification of flower shaped square pipe, open square pipe, corrugated square pipe and special-shaped square pipe square pipe is divided into hot-dip galvanized square pipe, electro galvanized square pipe, oil coated square pipe and pickling square pipe according to surface treatment. Square pipe is classified according to purpose & mdash& mdash; Square tubes for decoration, machine tools and equipment, machinery industry, chemical industry, steel structure, shipbuilding, automobile, steel beam and column and special purpose are classified by wall thickness & mdash& mdash; Super square tube, square tube and thin-walled square tube plasticity refers to the ability of metal materials to produce plastic deformation (deformation) without deformation under load.average method,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,PhoenixCold galvanized square pipe manufacturer, 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 it is not allowed to stack with acid, salt alkali 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, medium diameter steel pipe, 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, or thin-walled steel pipes, 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, and generally adopts ordinary closed warehouse, 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, so as to facilitate the implementation of the principle of first in, 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,Phoenix40 thickness of galvanized square pipe, it can be padded up by .M; If it is muddy ground, 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, 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 goodCold formed hollow section steel (American Standard) for cold pressed QB square tube (national standard) structure carbon steel cold-formed circular section and pressure welded QB square tube and seamless QB square tube (European standard) non alloy fine grain cold formed welded hollow structural profile (Japanese standard) angle steel QB square tube for general structure galvanized qb square tube for low pressure fluid transmission, Standard No.: gbt-. Representative materials: qqbqb, etc. it is mainly used to transport water gas, air, oil and water or steam. It is a special product manufacturing enterprise integrating R & D, and service. It has long been a professional square tube, square tube, seamless square tube, galvanized square tube and galvanized tube. Its purpose is only limited to general low-pressure fluid.Alloy steel: A. low alloy steel (total alloy element content & le; %); b. Medium alloy steel (total alloy element content > ~ %); c. High alloy steel (total alloy element content > %).Phoenix, 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.Hundreds of degrees Celsius, which can save energy.So flat, and the size and thickness are not standardized, it can reflect that this square tube is a poor product& rdquo;