WHAT AFFECT THE QUALITY OF FLANGES？

The flange is a kind of connecting part, which can be connected to the container, and can also be connected to the valve and pipeline. The connection method used for different containers is different. The flange has good strength and sealing effect. It is widely used in containers and pipes. Do you know how to distinguish the quality of the flange?

 

 

The type of flange

 

1.According to the chemical industry (HG) industry standard: flange can be divided into integral flange (IF), threaded flange (Th), plate type flat welding flange (PL), neck butt welding flange (WN), neck with flat welding flange (SO), socket Welding flange (SW), Butt welding ring loose sleeve flange (PJ / SE), Flat welding ring loose sleeve flange (PJ / RJ), Liner flange cover (BL (S)), Flange cover (BL) .

 

2.According to the petrochemical (SH) industry standard: flange can be divided into threaded flanges (PT), butt welding flanges (WN), flat welding flanges (SO), socket welding flanges (SW), loose sleeves Flange (LJ), flange cover.

 

3. According to the mechanical (JB) industry standard: flange can be divided into integral flange, butt welding flange, plate type flat welding flange, butt welding ring plate loose sleeve flange, flat welding ring plate loose sleeve flange and Side ring plate loose sleeve flange, flange cover.

 

4. According to national (GB) standards: flanges can be divided into integral flanges, threaded flanges, butt welding flanges, flat welding flanges with necks, socket welding flanges with necks, butt collars with neck loose sleeves Flange, plate type flat welding flange, butt welding ring plate loose sleeve flange, flat welding ring plate loose sleeve flange, flange ring plate loose sleeve flange, flange cover.

 

 

How to identify the quality of the flange

 

Type

The appearance can easily identify the type of flange. First, determine the top by determining if the flange has a flat surface, threaded holes, lap joints, weld neck, socket weld or tongue and groove. The next step is to identify the bottom by determining if the bottom has a flat or raised surface.

 

Size

The dimensions of the flange consist of the following factors, including the standard used (ANSI / DIN / JIS), the required pressure rating, and the actual dimensions of the flange. These factors include outer diameter, inner diameter, number of bolt holes, bolt hole diameter, and bolt circumference.

 

Thickness

Thickness plays a crucial role in determining the pressure that the flange can withstand, because thicker flanges can withstand higher pressures in applications.

 

Valve resistance

After the medium flows through the valve, there will be a pressure loss (the pressure difference between the front and rear of the valve), that is, the valve has a certain resistance to the flow of the medium, and the medium will consume a certain amount of energy in order to overcome the resistance of the valve;

 

Sealing performance

The sealing performance of a valve refers to the ability of each sealing part of the valve to prevent medium leakage, and it is the most important technical performance index of the valve.

Since different industries have different requirements for flanges, reasonable inspections must be carried out to ensure the quality requirements of flanges, pay attention to relevant precautions, and meet people's needs in production.