The advantage of empty bending is that it can bend the side length when the real bending cannot be carried out, such as synchronous bending and finishing of the upper side and side of qb square tube. Empty bend can also bend R & amp; amp; lt; .T without fracture of pipe wall.Due to the increase of square tube production, there are more and more fake and shoddy square tubes in the market. How to distinguish the fake and shoddy square tubes? Let me teach you some points to distinguish the fake and shoddy square tubes.Dordrecht,The difference between qb square tube and QA is that there are fewer impurities s and P and better low-temperature impact performance. From the welding point of view, when the impurity elements in the base metal are less, it is good for welding hot crack.At this time, if the welding wire of the same material is used for spot welding where the thickness is insufficient, it shall be welded to the fixed thickness, ground and sandblasted, and repair welding shall be adopted where there are cracks, even if the steel pipe with another large opening can be made up at one time.El-Coco, so that the steel sand, steel shot, iron wire section, minerals and other abrasives can be sprayed (thrown) on the surface of the square tube under the action of centrifugal force, which can not only completely remove rust,DordrechtHot dip galvanizing of square pipe,DordrechtDN65 galvanized round pipe, oxides and dirt, but also the square tube under the violent impact and force of abrasives, It can also achieve the required uniform roughness.The surface of galvanized square pipe treated by sand blasting, shot blasting or pickling process is relatively clean, and the oxide scale and rust are removed, which improves the adhesion of the coating. When the installation site unconditionally adopts sand blasting and shot blasting,DordrechtGalvanized pipe manufacturer, manual and mechanical derusting can be adopted, but the derusting quality level must be reached.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.

So flat, and the size and thickness are not standardized, high strength, good resistance, easy laying, low water resistance, low cost and corrosion resistance. Its service performance and economic benefits far exceed reinforced concrete pipe and general specification iron pipe. It is an updated product of engineering pipe.The difference between hot-dip galvanized square pipe and cold-dip galvanized square pipe is mainly from the following aspects: the appearance of hot-dip galvanized square pipe is slightly rough compared with cold-dip galvanized square pipe; The appearance of cold galvanized square pipe is smooth and bright.reform,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.C. electric furnace steel: (a) electric arc furnace steel; (b) Electroslag furnace steel; (c) Induction furnace steel; (d) Vacuum consumable furnace steel; (e) Electron beam furnace steel.The general delivery length of qb square pipe is mm-mm, mostly mm and mm. Qb square tube is allowed to deliver short length and non fixed length products not less than mm, or in the form of interface tube

Generally, chemical and electrolytic pickling are used for pickling treatment. Only chemical pickling is used for pipelines, which can remove oxide scale, rust and old coatings. Professional square tubes, rectangular tubes, galvanized square tubes and galvanized tubes are safe, environmentally friendly and economical! The products are exported to foreign countries and are deeply trusted. Sometimes they can be used as reprocessing after sand blasting and rust removal. Although chemical cleaning can make the surface reach a certain cleanliness and roughness its anchor lines are shallow and easy to pollute the environment.Inspection environment,Zinc layer thickness: there is a great difference between cold galvanized square pipe and hot galvanized square pipe in galvanizing process; Cold galvanized square pipes are prone to & ldquo; Electric burning & rdquo; The color of this part is gray and the zinc layer is thick. It is easy to form a current dead angle at the corner, resulting in an under current area. The zinc layer at this part is thin, and there is no zinc layer attached to the cold galvanized square pipe. The cold galvanized square pipe has no zinc lump and caking as a whole, but the overall zinc layer is thin and the thickness of the outer wall zinc layer is μ m-μ m. The and outer walls of the hot-dip galvanized square tube are attached with zinc layer, but the overall zinc layer is thick and there will be water marks and a few zinc tumors, and the thickness of the zinc layer on the inner and outer walls of the square tube is -mu; M above. The nature of QB square tube!However there is a large rate of end in the application of steel pipe, which is mainly due to the trouble of internal and external treatment. The primary external question is very crucial, and its external quality directly affects its application. fake and inferior square tubes are easy to fold. Folding is a variety of broken lines formed on the surface of square tubes, and this defect often runs through the longitudinal direction of the whole product. The reason for the folding is that the fake and shoddy manufacturers pursue the rate, the reduction is too large, resulting in ears, folding occurs during the next rolling, the folded products will crack after bending, and the strength of the square tube will be greatly reduced.Dordrecht,The strength, plasticity and angle discussed later are the machine function indicators of metal under static load. In practice, many mechanical machines are under repeated load, and the whole opportunity is tired in this environment.Precision inner diameter square tubes for hydraulic and pneumatic cylinders (gb-) are cold drawn or cold-rolled precision square tubes with precision inner diameter for hydraulic and pneumatic cylinders.According to metallographic classification