Protecting pipeline valves against aggressive media impact. MODENGY chemically resistant coatings

Operational conditions of pipeline valves. Issues at transporting aggressive media

Activity of the enterprises of oil, chemical, and many other industries is closely related to need of transporting aggressive media such as alkalis, acids, gas, oil products, etc.

Contact with chemical substances leads to corrosion and rapid destruction of the constructive materials, that’s why seek for effective ways to extend service life of the pipeline parts including lock valves, control valves, and other valve types is one of the priority tasks at producing and implementing these items into operating.

Pipeline valves must have high resistance towards corrosion and to aggressive media impact, be capable to be operated without need in frequent maintenance and repairs.

To provide these important features, MODENGY anti-friction solid-film coatings having high chemical resistance are used.

Chemically resistant coatings: principle of operation, and MODENGY products review

In order to extend service lifetime of pipeline valves parts, special lubricating-and-protective coatings that are realized under MODENGY brand are used.

 Fig.1 – MODENGY 1014 coating

They are made on basis of solid lubricating substances, and polymer resins are used as binding materials in such coatings.

In process of curing of these coatings, a thin chemically inert layer is formed on the treated surfaces which insulates them from environment factors impact.

High chemical resistance is one of the properties of some MODENGY anti-friction solid-film coatings along with low friction coefficient, high load-carrying capacity, wear-resistance, operability in dusty environment, and high anti-corrosive properties.

The coatings are applied by the standard methods of painting, and get polymerized at heating in a kiln according to the process message.

Examples of application of MODENGY coatings on the pipeline valves parts

Use of MODENGY coatings is an effective way to protect the flow parts, lead screws, globe valves, and other pipeline fitting parts what has been proved by a vast experience of application, and the test results at manufacturers and operators of this equipment.

The most popular products that are used to protect and lubricate the parts under conditions of exposure to chemically aggressive media are MODENGY 1014 (see Fig.1), and MODENGY 1005.

MODENGY 1014 coating based on molybdenum disulfide and polytetrafluorethylene has been widely used on the globe valve parts.

It is applied onto the flow part of the cases and connecting branches (see Fig.2), globe valve plugs in order to provide their standard operating within natural gas environment. Having high anti-corrosive properties (more than 672 hours according to the results of the accelerated test in salt mist according to ISO 9227 Standard), this product prevents corrosion damage improving reliability, and extending service lifetime of the equipment.

Fig.2 – MODENGY 1014 coating on the globe valve cases and connecting branches 

MODENGY 1014 effectively operates in contact with hydrochloric acid on the media separators (see Fig.3). It insulates sensitive elements of measuring instruments from contact with working fluids.

Fig.3 – MODENGY 1014 coating on the media separators

MODENGY anti-friction solid-film coatings are also used to protect heat exchanger plates. One of the heat-transfer agents in heat exchangers is sulfuric acid temperature of which can reach +170 ℃.

These materials are operable at low temperatures as well. For example, MODENGY 1005 based on molybdenum disulfide protects rack mechanisms of the axial type valves (see Fig.4) against gaseous helium impact at subzero temperature: -196 ℃.

Fig.4 – Rack gearings treated with MODENGY 1005 coating

MODENGY 1005 is also used to treat threaded elements of pipeline parts (see Fig.5). It reduces friction, prevents scuffing and damages at multiple screwing-unscrewing of the connections, protects against corrosion and chemically aggressive medium impact.

Fig.5 – Threaded connections of the pipeline valves parts treated with MODENGY 1005 coating

Besides, this coating is used for the purpose of preventing sticking, jamming, and corrosion of the pipeline valves lead screws (see Fig.6) under conditions of heavy loads, high and low temperatures, exposure to aggressive media. It stabilizes friction, and protects the parts against damages providing long service lifetime, and high reliable performance of this equipment.

Fig.6 – Pipeline valves lead screws treated with MODENGY 1005 coating

Conclusion

Increase of the items’ resistance towards chemically aggressive substances impact significantly extends service lifetime and reliable operating of the pipeline valves. For the purposes of preventing parts destruction at contact with the media to be transported as well as protecting against corrosion, and reducing friction, the materials of the MODENGY product line are used.