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Through conduit gate valves are manufactured as per standard API 6D. These valves are preferred for dirty (suspended/abrasive) or fouling service because of the fact that, unlike normal gate valves, their wedge/gate (closure member) is not open to flow stream and so free from jamming or obstruction. These valves are suitable for onshore and offshore application and can be used for isolation purposes.

This article looks at the history and properties of Nickel Aluminium Bronze to help understand why this material is often overlooked. On the contrary, Nickel Aluminium Bronze has good tensile strength, is suitable against cavitation (eg propellers in shipbuilding), does not embrittle at cryogenic temperatures, and is resistant to biofouling. Furthermore, advancements in computer simulation have also overcome traditional challenges in casting processes.

Die-formed expanded graphite rings are widely used as gland packings in modern process valves for higher temperatures. The development of this sealing solution started in the 1970s and is defined by the characteristics of the expanded graphite material.

Coatings for bulk valves is a topic that needs serious thought if complications and extra expense are to be avoided during project execution and during warranty period, says Tecnimont’s Sergio Volontè.

Multiport Selector Valves (MSVs) can play a key role to optimise engineering and management of production facilities, as well as testing of oil and gas wells. Conventional production manifolds are typically expensive, complex and difficult to maintain. Employing an MSV in place of many actuated valves can lead to several advantages, such as fewer automation systems; smaller, lighter and more reliable skids; overall lower cost for installation, commissioning, operation, maintenance and ownership.

A major problem with stem nut thread failure is that stem position is usually interpolated from the number of stem nut rotations. If the stem nut threads strip out, the stem nut will still turn but will give a false indication of position to the control room. Such a failure of control and indication on a valve could cause a critical safety or environmental incident. This paper reviews approaches to stem nut maintenance and introduces a more scientific approach to measure stem nut thread wear.

Hydrometallurgy is a method for obtaining metals from their ores. It is a technique within the field of extractive metallurgy involving the use of aqueous chemistry for the recovery of metals from ores, concentrates, and recycled or residual materials. Metal chemical processing techniques that complement hydrometallurgy are pyrometallurgy, vapor metallurgy and molten salt electrometallurgy.

There are a multitude of stem sealing solutions utilized throughout severe service, flow control applications. This article will explore various stem sealing solutions and the reasons one might choose them. We will dive further into the intricacies of typical severe service applications, high-cycle severe service applications and what happens when a valve must become fast-acting.

The application of the Optimov® program to some of our customer plants revealed that some families of wedge gate valves require higher torques in dynamic flow conditions than historically assumed. Valves inspections revealed that these high torques are caused by poor manufacturing processes of these valves. The Disc Factor of these valves was corrected through statistical analysis. The issue was solved through increase of the torque switch settings and replacement of the actuators when needed.

How big is the market for power plant valves? How big is the market for gas transmission valves? These are the most important questions in setting up a marketing program – or are they?