Steel Threaded Flange

The Applications Of Steel Threaded Flange

It is mainly used for the connection of galvanized water and gas steel pipes, and its sealing surface is smooth. The commonly used nominal pressures are 0.6MPa, 1.0 MPa, and 1.6 MPa.It should not be used where crevice corrosion or severe corrosion may occur.

Both coarse thread and fine thread screws are used for fastening.

Fine-thread screws are generally used to lock thin-walled parts and parts that require higher anti-vibration requirements. Fine threads have good self-locking performance, so they have strong resistance to vibration and loosening. However, due to the shallow depth of the threads, their ability to withstand greater pulling force is worse than that of coarse threads.

When no anti-loosening measures are taken, the anti-loosening effect of fine-thread threads is better than that of coarse-thread threads. They are generally used for thin-walled parts and parts with relatively high anti-vibration requirements.

When used for adjustment, fine threads have more advantages. Disadvantages of fine thread: It is not suitable for use on materials with too thick structure and poor strength. When the tightening force is too high, it is easy to slip.

Sealing Principle Of Steel Threaded Flange Connection

The leakage of steel threaded flange is mainly interface leakage and penetration leakage.

Interface leakage refers to the leakage of media along the gap between the flange and the gasket. The amount of leakage is mainly related to the gap size at the interface. It is the main form of leakage in flange connections.

Penetration leakage refers to the leakage of the medium through the capillary tube of the gasket body, which is mainly related to the structure and material of the gasket. The basic method to prevent fluid leakage is to increase the resistance to fluid flow at the sealing port.

When the pressure drop of the fluid medium passing through the sealing port is greater than the pressure difference on both sides of the sealing port (inside and outside the container), the fluid medium is sealed. This increase in pressure drop (positive force of medium flow) is achieved by increasing the sealing specific pressure on the sealing surface.

The sealing of the flange connection means that under the action of the bolt compression force, the gasket is deformed to fill the uneven gaps on the flange sealing surface, preventing fluid from leaking along the interface to achieve the purpose of sealing.

Factors Affecting Steel Threaded Flange Connection Sealing

The bolt preload must act evenly on the gasket. Therefore, when the pretightening force required for sealing is certain, reducing the bolt diameter and increasing the number of bolts is beneficial to sealing. Operating conditions refer to the pressure, temperature and physical and chemical properties of the medium connected to the system. The impact of simple pressure or medium factors on sealing is not critical. Only the combined effect of temperature, especially under fluctuating high temperatures, will seriously affect sealing performance.

Threaded Flange Valves And Flange Valves Mainly Have Different Connection Methods

Threaded flange valve refers to threaded connection flange.Flange valves are welded.

Usage

Threaded valves are generally used on small diameter pipes.

Flange valves are generally used on large diameter pipes, or depending on the design requirements.

Threaded Valve

Threaded valve is a kind of valve accessory, which mainly refers to the valve body with internal or external threads and threaded connection with the pipe. Threaded valves are usually used in normal and low pressure projects.

Flange Valve

The opening and closing part of Flange Gate Valve is a gate plate. The gate plate moves perpendicular to the fluid direction. The gate valve can only be fully opened or closed and cannot be adjusted or throttled.

After installing and tightening the steel threaded flange, make sure that at least two threads are exposed outside the nut. Before use, lubricate the bolts and nuts to ensure a low friction coefficient when tightening and to prevent slipping and corrosion.

 Stud threads, nut threads and contact surfaces must be degreased and dried before use and lubricated.Uniform lubricants should be properly used for bolt threads, nut threads, nut bearing surfaces, washers, and nut bearing surfaces on flanges; use high-temperature anti-seize agents as needed.