Classification of surface treatment square pipe is divided into hot-dip galvanized square pipe， electro galvanized square pipe， many new substances have taken place， 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，Large diameter square tube which is the way to isolate the oxygen in the air. Today，Galvanized pipe square pipeMarketing channel layout Market 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， 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.
mWhen sand blasting or manual mechanical derusting is used due to the falling off of the oxide scale of the galvanized square pipe， the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time， the surface of the galvanized square pipe is easy to rust again， square rectangular tubes， seamless square tubes， galvanized square tubes， galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material，Large diameter square tube the overstock of inventory is easy to expire. Therefore， the main indexes of the paint must be rechecked before use， and the paint can be used only when the results meet the standards.
The function index analysis of the square tube - the strength acts with great progress. The load on the parts is called the charge and trap load. The damage power of the square tube under the charge and trap load is called the charge and trap toughness.
EColweziStrength refers to the function that the square tube data is destroyed under static load (appropriate amount of plastic deformation or fracture)， because the action form of load includes tension， compression， meandering shear and so on， because the strength is also divided into tensile strength， compressive strength， flexural strength， shear strength and so on. There is often a definite connection between various strengths. In normal use，Large diameter square tube tensile strength is often used as the fundamental strength gauge.
XfHDPE plastic square pipe made according to the properties of square pipe has the advantages of light texture high strength， good resistance，Galvanized pipe square pipeMarketing channel layout Market 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.
D. do not cut your hands boring， especially for girls. Holding or fingers will bind themselves.
After isothermal quenching， qqb square tube will have excellent rolling fatigue characteristics and corrosion resistance. Wear resistance， fracture toughness， impact toughness and bending strength. Therefore， in the subsequent production and application，Galvanized pipe_ Galvanized square pipe_ Seamless steel pipe_ Square tube - Wuxi Jiahang qqb square tube will be used as the material of rolling mill flap ball screw. The qqb square tube of case hardening steel also has the surface compressive stress characteristics obtained by heat treatment， and its application range is expected to be improved and expanded.
wPulling square tube: it is the process of pulling the die hole of the rolled metal blank (shape， tube， product， etc.) into a section to reduce the length and increase. It is mostly used for cold processing.
BIt is learned from that when degreasing the square pipe， if there is dirt on the outer surface of the steel pipe， it can be washed with purified water and dried naturally， then soaked with degreasing agent with a dry cloth to remove the oil， and then dried in the open air. When degreasing the inner surface of the opposite pipe， the end of the pipe can be tightly blocked with a wooden plug or closed with other. The degreasing solvent with the volume of % - % of the pipe from the other end shall be sealed with a wooden plug， placed in a flat and clean place or on a workbench with sleepers for -min， and the pipe shall be rotated every min. If degreasing is required for stainless steel elbow， degreasing solvent shall be appropriately added to make it fully soaked. After degreasing， pour out the solvent in the pipe， dry the pipe with exhaust fan or dry it with oil-free compressed air or nitrogen， or dry it with natural air. Large diameter pipes can be manually scrubbed with cotton cloth dipped in solvent; The square tube can also be soaked in a long tank containing solvent for to minutes. The concentrated pipeline and equipment of the concentrated unit can be directly pumped and circulated with % concentrated for pickling after all installation. Pipes that cannot circulate or are not resistant to concentrated corrosion must be degreased separately.
TThe cheapestSample length L & asymp; D (D is the outer diameter of the pipe). When the outer diameter is large， the length l shall not exceed mm. When the outer diameter is less than mm， l = mm.
xRFunctional index analysis of square tube - commonly used are square tube Brinell angle (HB)， because the cast state of forged metal can be broken when forging qb square tube. Therefore， there are forging workshops in some qb square tube factories.
Now stainless steel is gradually replacing pure iron products in our life， the focus is on the analytical process of qb square tube sizing rolling.
originalnThe square tube represents the large capacity of the metal material under the action of tension the above small series are not the focus. Today， and the calculation formula is: where: FB -- the strong force borne by the sample when it is broken， n (Newton); So -- original cross-sectional area of sample， mm. Yield point (& sigma; s) the stress of metal material with yield phenomenon when the specimen can continue to elongate without increasing (keeping constant) the force during the tensile process， metal ceramic and metal metal welding.
The covering shall be strong and durable to prevent decay and leakage caused by long-term sun and rain.
oThe welding sequence is to reduce deformation. The welding sequence of rectangular butt welding shall adopt layered and symmetrical skip welding from the middle to both sides according to the following principles. The welding deformation is smaller than that of straight through welding， which is conducive to the dispersion and release of stress and avoid complex stress in weldments. During straight through welding， the narrow plastic deformation zone formed at the beginning of welding only occurs once. Moreover， due to continuous welding， the heat input is large， the heating area is large， and the plastic deformation area caused by compression is large， so the shrinkage deformation after welding is very large. In case of layered and segmented skip welding， the section of each layer is very small， and the heat required is small， and each layer is divided into several sections for skip welding. Each welding section basically re establishes the secondary temperature field on the cold steel plate， and a narrow plastic deformation zone appears each time. Therefore， the average width of the plastic deformation zone (i.e. the size of transverse shrinkage) is smaller than that of the corresponding layered straight through welding， and the longitudinal shrinkage is also smaller， The welding deformation is smaller than that of continuous filling.
vXStainless steel qb square pipe for mechanical structure， Standard No.: gbt-. Representative materials Cr cr crni CrNi crninb， etc. are mainly used for mechanical parts and structural parts such as machinery， automobile， bicycle， furniture， hotel and restaurant decoration.
The performance advantage of square tube after calcium treatment requires not only high strength， but also good machining performance. For sulfur-containing square tube sulfur can improve the machinability of steel， so the sulfide inclusion in square tube is the key to determine the quality of steel. Sulfur mainly exists in the form of MNs in the steel. The single MNS inclusion is light black strip. The inclusion with this morphology cuts off the continuity of the steel matrix and makes great differences in the anisotropic properties of the steel. Calcium treatment of molten steel can form MNS inclusions and combine MNS with al CAS to form composite spindle inclusions. Such inclusions can improve the machinability of steel and avoid the adverse impact of MNS inclusions on the properties of steel.