How to Select the Right Control Valve Materials for Corrosive Service

When handling corrosive materials, it is important to use appropriate materials for control valves. Equipment may be damaged, or the process efficiencymay be affected by corrosion. Fisher offers a variety of materials for control valves used in corrosive applications. Here’s how to choose the right materials for your needs.

Key Factors to Consider

Factors to Consider when Choosing Control Valve Materials for Corrosive Service. One of the first considerations is what type of corrosive is conducting the process. Each material resists corrosion from a different corrosive substance, so the corrosive substance being used is an important factor to consider when selecting a material.

Another consideration is the temperature and pressure of the process fluid. High temperature and pressure: some materials may not be able to tolerate high temperatures or pressures, it is important that you select a material based on the conditions of your process.

In addition, the rate of flow and the velocity of the process liquid should be considered in choosing control valve materials. Some materials are prone to high erosion or high corrosion at high flow so it is important to choose a material that can endure the flow conditions of the process.

Merits and Demerits for Corrosion Service

There are a number of types of materials which are commonly used for control valves to be used in corrosive service, each having its own advantages and disadvantages. Stainless is the most widely used material for control valves because of high corrosion resistance and good strength and toughness. But stainless steel is costly and is not suited for high-temperature or high-pressure operations.

Carbon steel is also used widely as a control valve material. Carbon steel Carbon steel is cheaper than stainless steel, and it is corrosion-resistant as well. But carbon steel can rust if not sufficiently coated or lined, so where corrosion resistance is a concern, you may need to opt for stainless.

How to assess material compatibility with process fluids

Material compatibility with process fluid To determine if the material is compatible with the hydraulic fluid, the chemical composition of the fluid and how it interacts with the material should be taken into account. The temperature, pressure and flow rate of the process fluid, and how they can interact with the material must also be taken into account.

Moreover, one should take into account any impurity or contaminant in the process fluid that can result in material corrosion and/or erosion. Running of tests and experimental work to compare material compatibility with process fluids can assist in ensuring the correct material has been selected for a particular application.

Significance of good coatings and linings in corrosive atmospheres

Where control valve materials are subjected to corrosion and erosion, adequate coatings and linings should be provided. The life of control valves can be prolonged and the risk of equipment damage reduced with coatings and linings.

Some common type of coatings and linings which are utilised in corrosive application are epoxy coating, rubber lining and ceramic coating. Such coatings and linings provide an additional line of defense against corrosion and offer the ability to maintain control valve materials in a condition that is resistant to chemical attack.

Suggestions and Recommendations in Control Valve Material Selection

When you need to choose control valve materials for harsh service, it is crucial to partner with suppliers like Xiangjing who knows the process' needs and can provide you the best recommendation on the materials for your application. When the types of corrosion and the temperature and pressure conditions are taken into account, as well the flow rate, and corrosive media being transported, it is also substantially relevant to consider what kind of impurities will accompany the transported gas.