Casting flange, blank shape and size accurate, small processing, low cost, but there are casting defects (pores, cracks, inclusions);Less streamlined internal structure of the casting (less streamlined if it is a cutting piece);Forging flanges generally contain less carbon than casting flanges and are not easy to rust. Forging parts are streamlined, compact and have better mechanical properties than casting flanges.Improper forging process will also appear large or uneven grain, hardening crack phenomenon, forging cost is higher than the casting flange.
Forgings can withstand higher shear and tensile forces than castings.The advantages of castings are that they can be manufactured with more complex shapes and lower costs.And the internal structure is uniform, no casting pores, inclusions and other harmful defects;From the production process, the difference between casting flange and forging flange, such as centrifugal flange is a kind of casting flange.
Centrifugal flange belongs to precision casting method, this kind of casting is finer than ordinary sand casting structure, quality improves a lot, it is not easy to appear the structure loose, stomata, trachoma and other problems.
Forging flange production process
Select high quality billet blanking, heating, forming, cooling after forging.The forging process includes free forging, die forging and die forging.During production, different forging methods are selected according to the quality and size of forgings and the number of production batches.
Basic process of free forging: in free forging, the shape of the forging is gradually forged into the blank through some basic deformation process.The basic processes of free forging include upsetting, drawing, punching, bending and cutting.
Upsetting is the process of forging the blank along the axis to reduce its height and increase its cross section.This process is often used to forge gear billets and other disc-shaped forgings.Upsetting can be divided into two categories: overall upsetting and local upsetting.
Drawing is a forging process that increases the length of the blank and reduces the section. It is usually used to produce the blanks of shaft parts, such as lathe spindle and connecting rod.
A forging process in which a punch is punched through or through a hole in the blank.
A forging process in which a blank is bent to an Angle or shape.
A forging process in which one part of the billet is rotated at an Angle to another.
The forging process of cutting and dividing the billet or cutting off the head.
Die forging is called model forging, in which the heated blank is placed in the forging die fixed on the die forging equipment.Basic procedures: blanking, heating, pre-forging, final forging, blanking and blanking, trimming, tempering and tempering, shot peening.Common processes are upsetting, drawing, bending, punching, forming.Common die forging equipment commonly used die forging equipment including die forging hammer, hot die forging press, flat forging machine and friction press.Tell popularly, forging flange quality is better, it is to pass die forging production commonly, crystal structure is close, intensity is high, of course the price also is a few more expensive.
Cutting system of the flange
In the middle plate directly cut out the flange left with the amount of inner and outer diameter and thickness of the disc, and then the bolt hole and waterline processing.The flanges produced in this way are called cut flanges. The maximum diameter of such flanges is limited to the width of the plate.
The process of cutting strips with a medium plate and then rolling them into a circle is called coiling and is often used in the production of some large flanges.After the successful rolling of welding, then flattening, and then the waterline and bolt hole processing process.