Preventing Damage To Process Controls at Oil & Gas Refineries

In a refinery setting, fire and explosion safety are paramount concerns. The potential harm to people and property is immense. Therefore, it is important to take appropriate steps to prevent, contain and extinguish any fire hazards. Protecting process controls is particularly important. Avoiding damage to these systems can help to mitigate the impact of a refinery fire.

Protecting Process Controls

When a fire or explosive hazard occurs in an oil and gas refinery, the fire and gas safety system must activate. Additionally, the process control system must take automated, preventative steps to avoid the situation from worsening. If process controls in the refinery are damaged by fire or explosion, it could lead to the danger rapidly worsening.

•       Fire-Resistant Enclosures: Many manufacturers and suppliers offer fire-resistant enclosures for control systems. These are available as flexible, semi-rigid and rigid options. Resistance ratings vary but some are capable of protecting components from 2,200°F temperatures for up to 120 minutes. Many rigid solutions are also resistant to blast overpressure.

•       Fire-Retardant Coating: Another solution that can be applied to existing equipment, fire retardant coatings can provide 30+ minutes of protection at up to 2,000°F. This option is very space-efficient, durable and weatherproof. However, coatings offer little to no blast resistance.

•       Fire-Resistant Components: Some control system components are designed to be fire and explosion-resistant with no added enclosure or coating. These options are highly effective, especially when combined with other solutions. However, they are often new components that requires replacing existing equipment.

A combination of the above protective solutions for critical components and integration between fire and gas systems and the process control system is advisable. Automatically enabling an emergency shutdown as soon as a hazard is detected helps contain the problem. However, this is only possible if the control systems are sufficiently heat and blast resistant.

Actuators for High Temperature and Explosive Situations

Actuators play a major role in the control of refinery equipment. Standard pneumatic actuators may not be sufficiently resilient to handle the temperature extremes and pressures of an oil and gas refinery. Sourcing from the right valve actuator manufacturer can help ensure high-quality actuators for your high temperature situations. An explosion proof valve actuator that can stand up to the rigors of fire and gas hazards is worth the investment.

Refinery engineers should strongly consider process control solutions that are designed for the oil and gas industry. Valve control actuators for oil refineries and gas transmission purposes are often tested for shock, heat exposure and hazardous conditions. These could make the difference between a contained explosion and serious damage to the refinery and potentially people.

Summary

Combatting fires and explosions in a refinery is no simple undertaking. The potential impact is so immense that comprehensive, preventative solutions are necessary. Combining automation with fire-resistant enclosures, coatings and components can ensure that a minor fire or explosion does not turn into a catastrophe.

Advanced Actuation & Automation Processes in Gas Lines

Precision and safety are critical in the oil and gas industry. Automation using flow control valve actuators optimizes efficiency, modulates the flow of gas or liquid, increases safety for operators and decreases maintenance and operating costs over time. The automation industry has recognized that the function of actuators has moved beyond just opening and closing valves to providing key diagnostic and operational data via Bluetooth interfaces from sensors that measure pressure, torque and vibration. The types of actuators needed are dependent on a variety of factors.

Types of Valves

The types of valves controlled by the actuators determine the actuator used. The actuator must be matched to the following characteristics of the valves:

• Function

• Movement

• Position

The frequency that the valves are used varies with the function of the valves. Those that open up or close off the flow completely for maintenance or safety reasons are used less frequently than those that continually modulate the flow of gas or liquid. Similarly, the movement of the valves varies with the type of valve, requiring actuation. Controls for ball valves require a swivel movement provided by a quarter-turn actuator, while a multi-turn actuator would enable the many turns required to open or close a valve.

Precision is key in oil and gas transmission and electric actuators can provide superior positioning accuracy. Position accuracy is important for control valves that modulate the flow during the various stages. From the initial flow of crude oil and natural gas to storage and transportation, then finally to the refining and distribution process, the valves modulate not only the flow rate and pressure through the various pipe diameters but the rate that the oil or gas is fed into the various processes along the way.

Processes

The more processes involved, the more actuators are needed to manage the complexity of the system. We recommend you work closely with your electric actuator manufacturer to help configure a solution that is right for your needs. Sensor technology has expanded the use of flow control valve actuators to allow for monitoring in real-time and integration into IIoT (Industrial Internet of Things). Much like the smart electronics being used in factories and homes, the controls for ball valves have embraced smart technology to deliver improved flow control. Integration with supervisory control systems enables next-generation processes such as asset management on a plant-wide scale and optimized maintenance control and scheduling. Integrated operations combined with wireless communication provide operational information at a faster rate, allowing more processes to be managed with fewer resources but with increased accuracy, efficiency and response time.

Opening and Closing Big Valves Within a Wastewater Treatment Plant

For townships and cities that maintain a central sewer system, it is important to treat the wastewater and make it safe for release back into the environment. The mechanical operations of flow control valves, actuators, circulation tanks and gates help treatment plants manage the flow of wastewater during this process.

Today, more Americans than ever believe in environmental protection. After all, there is no doubt that improper waste management leads to contamination and the spread of diseases. This makes it all the more important for municipalities to ensure they have full control over the flow of all substances in and out of these treatment plants.

Mistakes can be costly and valve failure must be prevented. This is just one of the many reasons so many municipalities rely on electric actuators over hydraulic or pneumatic actuators.

A Brief History of Waste Treatment

In 1948, Congress signed the Federal Water Pollution Control Act to address the contamination of water supply systems. As awareness grew in America, it created enough momentum to pass the 1972 Clean Water Act. Not only do homes and businesses need to abide by the 1972 law, but municipalities need to as well.

Since then, there have been several amendments to strengthen the law and to provide more leeway to the EPA to implement programs aimed at solving pollution problems. Wastewater treatment plays a significant role in this goal.

The Needs of the Treatment Plant

Municipality maintenance crews are beholden to check and maintain the integrity of the rotary actuators for valves and gates that help to manage the flow of water and wastewater sludge. Periodic testing is mandatory to help keep the system stable. The flow of wastewater through primary and secondary clarifiers must not be impeded upon and the cleaning of debris and grit screens daily ids a must. The chlorination process works best when the majority of heavy particulates are removed before chlorination. Often the controls for butterfly valves is what impedes water flow, especially if older hydraulic equipment is not well maintained. These pages do a good job defining what is a hydraulic actuator and what is a pneumatic actuator.

Each treatment plant is different and should be evaluated as an independent unit. However, all treatment plants prioritize the release of safe substances back into the environment well after the dichlorination process and final filtering with sodium bisulfate. Problems occur when there is faulty equipment in the flow of water and sludge water. This flow requires the use of heavy-duty valves built to handle wastewater that may also hold suspended solids and reliable actuators for wastewater treatment applications. The valves, in turn, need the right controls to ensure maximum precision.

The Importance of Precision

When it comes to wastewater management, engineers and operators must be able to maintain the controls for these butterfly valves and wastewater gates. Selecting a good valve actuator manufacturer to evaluate the needs before selecting the right equipment can help. Opening and closing these big valves requires not just the right equipment from a reputable valve actuator manufacturer to stand behind their equipment.

Even a small glitch can wreak havoc. For shut off valves that workers may control manually, opening and closing at the wrong time may not only lead to contamination but valve damage.

Industrial Linear Actuators that work best in Hazardous Situations

It is understood that precision and reliability are the primary reasons why mechanical engineers prefer using electric linear actuators over fluid power actuators in critical powertrain applications. But what about in high temperature environments and combustible situations? Some electric linear actuator manufacturers have developed solutions that you may find interesting.

Pneumatic actuators have been the standard for design engineers in hazardous environments due to the lack of an electrical power source. But they are often prone to air leaks, they tend to be larger in size and the stop point precision is not as exacting as their electronic cousins. When precise reliable linear motion is required, electric linear actuation offers some very compelling benefits. Since maintenance and repairs of pneumatic actuators needs to be included into the equation, electric actuators tend to be more durable over time and therefore more economical over the long term.

Making Hazardous Situations More Tolerable

Several manufacturers of explosion proof valve actuators are using NEMA class VII enclosures for the exterior metal castings for certain actuators. This classification of material improves its ability to withstand high impact explosions and prevent penetration from toxic liquids. Flexible designs allow the digital control module, circuitry and critical wiring to be separated from the gear train and mechanical operations of the actuator and therefore can be positioned a safer distance from high temperatures. The most common concerns for analysis include explosions, fire, and shock hazards. Combustible materials such as acetylene, liquefied petroleum gas, hydrogen, methane, propane, alkali metals, magnesium metal, and metallic hydrides, all fall into the hazardous materials category. Today a 120 V linear actuator can be made impenetrable to these hazardous materials and made more compact than the clunkier pneumatic actuators that do similar tasks.

What is Pneumatic Actuation

These types of actuators operate using compressed gas. The compressed gas then generates force and induces motion of a piston. The air compressor serves as the power source of pneumatic actuators. They tend to be simple and durable, and good for high-speed operations. Use of a pneumatic actuator with modern controls typically requires an analog converter for delivering a control signal setpoint. This is a primary drawback since technology developments in the past 10 years has gone beyond this older methodology.

Conclusion

Both pneumatic and electric rotary actuators work best in hazardous situations where there are large air flow dampers involved. A 120 V linear actuator that has been built to NEMA VII specifications and has a flexible electronics compartment is often a wise choice to tight locations were precision and reliability are of utmost importance. There are several electric actuator manufacturers in the USA that are making high quality industrial actuators that are designed specifically for hazardous environments.