Metal Bellows Sealed Globe Valve (PN16)

Catalog Code: T-0175

Metal Bellows Sealed Globe Valve (PN16)

Metal Bellows Sealed Globe Valves are valves in the globe valves group, working with metal to metal sealing. Thanks to the high temperature resistant parts used in its design, it can be used in steam lines, hot oil systems, hot and cold water systems with the highest efficiency. 

The difference of these valves, which are generally used in steam lines, from globe valves is the bellows system in them. The bellows is mounted between the cover and the body and acts as an extra sealing element between the fluid and the cover. Apart from this, it also provides a more controlled opening and closing of the valve. Since the bellows are welded to the stem and not to the flapper, the vibration from the flapper is reflected to the bellows and no disturbing sound is heard. Thanks to the bellows, a smoother opening can be achieved. In case of shaft breakage or deformation due to use or production, the bellows system prevents the fluid from coming out as safety.

Bellows are manufactured in stainless materials with high corrosion resistance. AISI 316 and 316Ti quality stainless steel are the most preferred bellows materials.

According to the design of the sealing element, the way the valve is opened varies. While flat surfaces open directly and quickly, conical designs open more slowly and in a controlled manner. This minimises the possibility of ram impact that may occur in the installations.

Apart from this, conical valves also have different advantages. At the beginning of these, since there is a taper (angular) in the site and the valve, there is less chance of unwanted particles remaining. Since there is linear contact, sealing is provided at lower torque values. Since the contact surface is less, the amount of deformation in both the valve and the seat is minimised.

In order to prevent leakage of the fluid to the atmosphere, sealing elements should be selected as resistant to high temperatures. Graphite based materials are generally used in metal bellows valves.

One of the most important differences from globe valves is that it has a level indicator that moves with the shaft and shows the open or closed position of the valve. In this way, it is possible to have an idea about the condition of the valve from a distance.

Metal Bellows Sealed Glob Valves are valves used in one direction. It is important to connect to the installations in the direction specified by the manufacturer. If this is not taken into consideration, the life of the valve will be shortened.