Blind plate flange is also called blind plate, and the correct name is called flange cover. It is a flange without a hole in the middle, which is used to seal the pipe plug. There are many types of sealing surfaces, including flat, convex, concave-convex, tongue and groove, and ring connection surfaces.
The production process is mainly divided into forging, casting and cutting.
Cast flange and forged flange
The cast flange has accurate rough shape and size, small processing volume and low cost, but it has casting defects (pores, cracks, inclusions); the internal structure of the casting is poorly streamlined (if it is a cutting part, the streamline is worse);
Forged flanges generally have lower carbon content than cast flanges and are not easy to rust. Forgings have better streamlined shape, denser structure, and better mechanical properties than cast flanges;
Improper forging process will also cause large or uneven crystal grains, hardening cracks, and forging costs higher than cast flanges.
Forgings can withstand higher shear and tensile forces than castings.
The advantage of castings is that they can produce more complex shapes and lower costs;
The advantage of forgings is that the internal structure is uniform, and there are no harmful defects such as pores and inclusions in the casting;
From the production process, the difference between cast flange and forged flange is different. For example, centrifugal flange is a kind of cast flange.
Centrifugal flanges belong to the precision casting method to produce flanges. Compared with ordinary sand casting, the structure of this type of casting is much finer, and the quality is improved a lot. It is not easy to have problems such as loose structure, pores, and trachoma.
First of all, we need to understand how the centrifugal flange is produced, the process method and product of the centrifugal casting to make the flat welded flange, which is characterized in that the product is processed through the following process steps:
①Put the selected raw material steel into an intermediate frequency electric furnace for smelting, so that the molten steel temperature reaches 1600-1700℃;
②Preheat the metal mold to 800-900℃ to maintain a constant temperature;
③Start the centrifuge, inject the molten steel in step ① into the metal mold after preheating in step ②;
④The casting is naturally cooled to 800-900℃ and kept for 1-10 minutes;
⑤Cool it with water to near normal temperature, demould and take out the casting.
