sampling quantity

The inspection items, 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 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 bending can also bend the inner corner of r.t without breaking the tube wall.Villa altagrasia,The purpose of heat is to prevent the generation of cold cracks. Cold crack is directly related to carbon equivalent. Therefore, it is necessary to distinguish the carbon equivalent of the qb square tube,Villa altagrasiaGalvanized square pipe manufacturing, and the carbon equivalent of the qb square tube is the same. If the carbon equivalent of Q is less than .%, it can be said that the weldability is OK. Generally speaking, the cold crack increases when the carbon equivalent is .%. special shaped square pipe is the general name of square pipes with other cross-section shapes except circular pipe. According to the different cross-section shape and size of steel pipe, it can be divided into special-shaped square pipe with equal wall thickness (code D), special-shaped square pipe with unequal wall thickness (code BD) and special-shaped seamless steel pipe with variable diameter (code D) These special-shaped large-diameter qb square tubes are widely used in various structural parts, tools and mechanical parts. Compared with circular tubes,Villa altagrasiaHot dip galvanized steel pipe for inner and outer wall, special-shaped tubes generally have large moment of inertia and section modulus, and have large bending and torsion resistance, which can greatly reduce the structural weight and save steel. Square tubes are an indispensable part of construction workBojnurd,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, compared with straight seam pipe of the same length, 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,Villa altagrasiaGalvanized steel square pipe, galvanized square 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.Main uses of square tube: square tube is mainly used in tap water engineering, petrochemical industry, chemical industry, pig iron, ferroalloy cast iron, etc. Steel and pig iron are alloys based on iron square tube and carbon as the main added element, collectively referred to as iron carbon alloy.

If there is only a single plane weld, the step-by-step back welding shall be adopted from the middle, that is the arc of the section weld shall be terminated at the section arc.All seamless qb square tubes shall be tested for mechanical properties. Mechanical property tests are mainly divided into two categories: tensile test and hardness test.For improper stamping direction, simulation software shall be used in the initial stage of design to ensure that the direction of stamping parts is analyzed, and when the high-quality requirements of components require the re development of molds, the direction shall be adjusted to seamless square tubes. The square tube manufacturer introduces the forming, bending and bending of square tubes. As the name suggests, the bending is compacted, and the inner and outer rollers are double with the inner and outer walls of tube billets during actual bending Compact towards the.how,Square tube heating process square tube calculates the chip thickness of workpiece. After each regrinding, the main drive AC motor spindle rotates stepless speed change AC motor feed capacity stepless speed change feed fast return to a constant value center system brush device hydraulic saw cutting system system system represents the quality RA flatness, large burr height cutting Chip length tolerance dimension: width and length . ~ .mm ~ m ~ ~ min kW ~ rpm ( kw ~ mmmin mmmin .kw .kw & times; kW S & mu; m . mm & plusmn; mm about mm about mm about mm high. The total weight of each billet square tube is seconds (including, pipe blank cutting, saw blade return, opening device, pipe blank discharge, head and tail cutting time, but excluding pipe blank transportation time). The large production capacity of the three saws is T / A. the pipe blank saw has a special reversing device (hydraulic servo device) to reduce vibration and improve the service life of the saw (only during feeding). The sawing machine has two devices distributed at the inlet and outlet (the input area is supported by roller table to ensure the bending of billet) The inlet end after sawing. Open it to ensure that the saw blade does not contact the blank when it returns. & mdash; feed saw gear & mdash; saw gear vibration reduction, which is composed of a fixed gear vibration reduction, as a movable vibration reduction to avoid the axial of the saw blade. & mdash; brush and sweep device & mdash; a driving brush and sweep device is installed at the bottom of the saw blade to clean the iron filings on the teeth and will not affect the service life of the saw blade. &Mdash; saw blade. In order to improve the service life of the saw blade, there is a feeding bench for single size billets that need to be cut, and after weighing, there is a feeding bench for returned billets). The buffer transfer chain transports the billets to the lower roller table of the loader. The billets are turned over from the chain to the roller table by the turnover hook. The weighed qualified billets are loaded into the annular furnace by the loader, and the weighed unqualified billets are transported from the roller table to the removal bench for removal.The disadvantage of empty bending is that during synchronous empty bending at the upper and side due to the pressure generated by the upper roll and the lower roll at the same time, the forming force is easy to exceed the critical point. All kinds of square tubes, square rectangular tubes, seamless square tubes, galvanized square tubes and galvanized tubes have formal qualifications. Welcome to telephone inquiry and sincerely invite cooperation! It will cause edge instability and concave, and will also affect the stable operation of the unit and forming quality. This is also the different characteristics of qb square tube and round tube empty bending.High density may not be obtained by simple pressurization, and insulation shall be carried out at the same time.

According to metallographic classification, the annealed state of square tube: A. hypoeutectoid steel (ferrite + pearlite); b. Eutectoid steel (pearlite); c. Steel precipitation through a common square tube (pearlite + cementite); d. Ledeburite steel (pearlite + cementite).technological innovation,Square pipe welding is suitable for surface treatment of materials. Square pipe welding can be used for ceramic ceramic, metal ceramic and metal metal welding.Large diameter welded square pipe for low pressure fluid transmission, Standard No.: gbt-. Representative material: grade qab. It is mainly used to transport low-pressure fluids such as water, sewage, gas, air and heating steam.Normalized: A. pearlite steel; b. Bainitic steel; c. Martensitic steel; d. Austenitic steel.Villa altagrasia,Square tube plays an important role in the rapid economic development. The functions of square tube are different, and its characteristics are also different. Square tube has strict standards. There are many welding processes and advantages of square tube. Let me show you the welding process and advantages of lower tube.Functional index analysis of qb square tube - angular plasticity refers to the power of plastic deformation (permanent deformation) without destruction of qb square tube data under load.Steel used & mdash& mdash; Such as bridge steel, ship steel, boiler steel, pressure vessel steel, agricultural machinery steel, etc.