Safety shut-off valves for the oil and petrochemical industries
September 2003
Valves, Actuators & Pump Control
Training & Education
The Maxon Corporation of the USA is a primary supplier of safety shut-off valves to the combustion industry. Known internationally for their reliability, longevity and compliance with international safety codes, they are often a first choice for engineers designing combustion pipetrains, whether the fuel is gas or oil.
Working on the principle that a constant electrical signal is required to keep them open (or closed, in the case of a normally closed valve), they are suitable for critical applications where interlocks are required to be healthy before the valve can be opened and remain open. Should this interlock be lost at any time during the process, the valve will immediately slam shut, thus isolating the upstream source from the downstream plant. This fail-safe action also takes care of cable-breaks.
The South American petrochemical industry has become an active user of the full range of Maxon Safety Shut-off valves. These valves are also used for the manual or motorised opening or closing of pipelines carrying gases or liquids, commonly used in industrial processes. Motorised automatic valve actuators are used where remote access or unmanned applications are needed. Manual reset actuators require operating personnel to be physically present to actuate the valve from its at-rest position.
All Maxon valves feature one-piece cast-iron or cast steel bodies with micro-lapped seats and discs. Straight through flow path minimises pressure drop through full open swinging gate or rising stem (guillotine action) bodies.
The rising stem principle of operation is well known in the industry and is used extensively in normally closed and normally open gas valves. The swinging gate valve has been specifically developed for oil applications. A hard-faced, micro-lapped seat nut is threaded into the one-piece valve body. The free-floating, hard faced, spring loaded circular disc swings across the seat. Line pressure assists in sealing the disc to the downstream seat. Frequent use and cycling actually helps to keep the valve clean. The disc rotates slightly on every cycle, providing a fresh, clean surface area for sealing off the flow lines.
Maxon is represented solely in South Africa by The Combustion Group in Sebenza. Its engineers are available for application advice and the Maxon test centre is on hand for unusual or difficult applications.
For more information contact The Combustion Group, 011 452 5060, [email protected], www.combustion.co.za
Further reading:
Gallagher Security achieves ISO 27001 recertification
News & Events Training & Education
Gallagher Security has successfully achieved certification to the updated ISO/IEC 27001:2022 standard for Information Security Management Systems (ISMS). This accomplishment builds on previous certifications and reflects a continued commitment to the highest standards of information security.
Read more...
A new generational framework
Editor's Choice Training & Education
Beyond Generation X, and Millennials, Dr Chris Blair discusses the seven decades of technological evolution and the generations they defined, from the 1960’s Mainframe Cohort, to the 2020’s AI Navigators.
Read more...
Ball valves and actuators optimise HVAC performance
Schneider Electric South Africa
Valves, Actuators & Pump Control
Schneider Electric offers the full range of innovative SpaceLogic and EasyLogic ball valves and actuators. These cutting-edge products are designed to optimise HVAC system performance, ensuring comfort and energy efficiency in commercial and residential buildings.
Read more...
Key design considerations for a control room
Leaderware
Editor's Choice Surveillance Training & Education
If you are designing or upgrading a control room, or even reviewing or auditing an existing control room, there are a number of design factors that one would need to consider.
Read more...
Alfa Laval expands hygienic valve portfolio
Valves, Actuators & Pump Control
Alfa Laval is expanding its hygienic valve portfolio by introducing the Unique SSV pressure relief valve and the Leakage Detection butterfly valve, alongside new smaller sizes of the Unique Mixproof CIP and Unique Mixproof process valves.
Read more...
Preparing pump systems for adverse weather conditions
Valves, Actuators & Pump Control
As the severity of storms in South Africa increases, so has the rush of sediment-laden water become a major issue and a significant challenge for irrigation. When sediment levels rise to just 10 grams per litre or more, the risk of pump wear and dam silting increases dramatically.
Read more...
The deepfake crisis is here and now
Information Security Training & Education
Deepfakes are a growing cybersecurity threat that blur the line between reality and fiction. These AI-generated synthetic media have evolved from technological curiosities to sophisticated weapons of digital deception, costing companies upwards of $600 000 each.
Read more...
CCTV control room operator job description
Leaderware
Editor's Choice Surveillance Training & Education
Control room operators are still critical components of security operations and will remain so for the foreseeable future, despite the advances of AI, which serves as a vital enhancement to the human operator.
Read more...
Strong industry ties set Securex South Africa apart
News & Events Training & Education
Securex South Africa, co-located with A-OSH EXPO, Facilities Management Expo, and Firexpo, is a meeting place of minds, where leading security, safety, fire, and facilities professionals come together, backed by strong ties with the industry’s most influential bodies.
Read more...
High-flow solenoid valve
Emerson Automation Solutions
Valves, Actuators & Pump Control
Emerson has introduced the new ASCO Series 327C solenoid valve, which features a direct-acting, high-flow design that provides superior flow-to-power ratio. It permits high flows at minimum power levels, making it ideal for use in power plants, refineries, and chemical processing facilities.
Read more...
printer friendly version