The Brief Introduction of Forged Flange

Forged Flanges, also known as flanges, include flanges or forged flanges. As a disc-shaped component, flanges are extremely common in boiler and pipeline engineering, mainly used for connecting pipe ends. The usual practice is to install a flange at each pipeline interface that needs to be connected, and some people also place it on the inlet and outlet of the equipment to connect the two devices. So, any connecting part that uses bolts to connect two planes around the periphery and seal them together is generally called a "flange".

The flange materials include cast iron, carbon steel, alloy steel, stainless steel, etc., specifically including WCB (carbon steel), LC3 (3.5% nickel steel), WC9 (2.25% chromium), CA6NM (4 (12% chromium steel), CF8M (316 stainless steel), CN7M (alloy steel), M35-1 (Monel), N7M (Hastelloy B), CY40 (Inconel), etc.

Classification of flanges: According to their overall properties, they can be divided into integral flanges, loose flanges, and arbitrary flanges, among which integral flanges can be further subdivided into flat welding flanges and butt welding flanges; According to their shape, they can be divided into circular flanges, square flanges, and elliptical flanges.

The production process of flanges mainly includes four types: forging, casting, cutting, and rolling. Generally speaking, forged flanges have better quality and are produced through die forging. They have a fine crystal structure, high strength, and are more expensive than flanges made by other methods.

Flange connection: Flanges are divided into threaded connections (threaded connections) and welded flanges. Low pressure small diameter threaded flanges are used, while high pressure and low pressure large diameter flanges are welded. The thickness of flange plates and the diameter and quantity of connecting bolts vary for different pressures.

The main factors affecting flange sealing are: bolt pre tightening force, sealing surface type, gasket performance, flange stiffness, and operating conditions.

The standards and usage of flanges: There are two types of flange standards used in petroleum and chemical industries, one is pressure vessel flange standards, and the other is pipe flange standards. The pressure vessel flanges here are divided into flat welding flanges and butt welding flanges, with flat welding flanges including Type A and Type B. Both flat welding and butt welding flanges come in two types: those with lining rings and those without lining rings. The pipe flange is based on the long neck as the standard, and the long neck butt welded flange has a thicker neck with greater rigidity.

The flange size is determined by the flange standard based on the nominal diameter and nominal pressure. The nominal diameter of the flange of the pressure vessel is the same as that of the pressure vessel; The nominal pressure of the flange is related to the operating pressure, operating temperature, and material. The dimensions of container flanges and pipe flanges with the same nominal diameter are different and cannot be used interchangeably.