A234 WP5 Alloy Steel Pipe Fittings 90 Deg LR Elbow Seamless Carbon Steel Elbow/Alloy Steel Elbow

The main alloying elements of alloy steel are silicon, manganese, chromium, nickel, molybdenum, tungsten, vanadium, titanium, niobium, zirconium, cobalt, aluminum, copper, boron, rare earth, etc. Among them, vanadium, titanium, niobium, zirconium, etc. are strong carbide forming elements in steel. As long as there is enough carbon, under appropriate conditions, their respective carbides can be formed. When carbon is lacking or under high temperature conditions, atomic The state enters the solid solution; manganese, chromium, tungsten, and molybdenum are carbide forming elements, some of which enter the solid solution in an atomic state, and the other part forms a substitutional alloy cementite; aluminum, copper, nickel, cobalt, silicon, etc. are not formed. Carbide elements generally exist in solid solution in an atomic state.

There are many types of alloy steel, usually divided into low alloy steel (content <5%), medium alloy steel (content 5% ~ 10%), high alloy steel (content > 10%) according to the content of alloying elements; according to quality, it is divided into high-quality steel Alloy steel, special alloy steel; according to characteristics and uses, it is divided into alloy structural steel, stainless steel, acid-resistant steel, wear-resistant steel, heat-resistant steel, alloy tool steel, rolling bearing steel, alloy spring steel and special performance steel (such as soft magnetic steel). , permanent magnet steel, non-magnetic steel) and so on.

In piping systems, elbows are pipe fittings that change the direction of piping. According to the angle, there are three most commonly used ones: 45° and 90° and 180°. In addition, according to the needs of the project, other abnormal angle elbows such as 60° are also included. The materials of elbows are cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, non-ferrous metals and plastics.

The ways to connect with the pipe are: direct welding (the most common way) flange connection, hot melt connection, electrofusion connection, threaded connection and socket connection, etc. According to the production process, it can be divided into: welding elbow, stamping elbow, push elbow, casting elbow, butt welding elbow, etc. Other names: 90 degree elbow, right angle bend, etc.

Seamless Elbow: Elbow is a type of pipe fitting used in pipe bends. Among all the pipe fittings used in the pipeline system, the proportion is the largest, about 80%. Usually, different forming processes are selected for elbows of different materials or wall thicknesses. Commonly used seamless elbow forming processes in manufacturers include hot pushing, stamping, extrusion, etc.

Stamping and forming elbow is the earliest forming process applied to mass production of seamless elbows. It has been replaced by hot push method or other forming processes in the production of elbows of common specifications. Less, the wall thickness is too thick or too thin.

The product is still in use when there are special requirements. The stamping forming of the elbow adopts the tube blank equal to the outer diameter of the elbow, which is directly pressed in the mold using a press.

Before stamping, the tube blank is placed on the lower die, the inner core and end die are loaded into the tube blank, the upper die moves downward to start pressing, and the elbow is formed by the restraint of the outer die and the support of the inner die.

Compared with the hot push process, the appearance quality of stamping forming is not as good as the former; the outer arc of the stamping elbow is in a stretched state during forming, and there is no excess metal in other parts to compensate, so the wall thickness at the outer arc is about 10% thinner. . However, due to the characteristics of being suitable for single-piece production and low cost, the stamping elbow process is mostly used for the manufacture of small batches and thick-walled elbows.

Stamping elbows are divided into cold stamping and hot stamping. Usually, cold stamping or hot stamping is selected according to material properties and equipment capabilities.

The forming process of the cold extrusion elbow is to use a special elbow forming machine to put the tube blank into the outer die. Clearance movement to complete the forming process.

The elbow manufactured by the internal and external die cold extrusion process has beautiful appearance, uniform wall thickness and small size deviation. Therefore, this process is mostly used for the forming of stainless steel elbows, especially thin-walled stainless steel elbows. The inner and outer molds used in this process have high precision requirements; the requirements for the wall thickness deviation of the tube blank are also relatively strict.

Welding of medium plate

Use a medium plate to make half of the elbow section with a press, then weld the two sections together. This process is generally used for elbows above DN700.