CTi is a Northern California based rep/engineering firm focused on providing integrated solutions for; valves, actuators, and controls. In addition we have expertise in the area of combustion & burner management controls and related components.
CTi maintains a California General Engineering Contractors License # 951993. Headquartered in San Ramon, CA, reach us at 925-208-4250 or CTi-CT.com
Showing posts with label industrial control. Show all posts
Showing posts with label industrial control. Show all posts
Cars are something which exist as part of the backbone of modern society, for both personal and professional use. Automobiles, while being everyday objects, also contain systems which need to be constantly maintained and in-sequence to ensure the safety of both the machine and the driver. One of the most essential elements of car ownership is the understanding of how heat and temperature can impact a car’s operation. Likewise, regulating temperature in industrial operations, which is akin to controlling heat, is a key process control variable relating to both product excellence and operator safety. Since temperature is a fundamental aspect of both industrial and consumer life, heat management must be accurate, consistent, and predictable.
A common design of heat exchangers used in the oil refining and chemical processing industries is the shell and tube heat exchanger. A pressure vessel, the shell, contains a bundle of tubes. One fluid flows within the tubes while another floods the shell and contacts the outer tube surface. Heat energy conducts through the tube wall from the warmer to the cooler substance, completing the transfer of heat between the two distinct substances. These fluids can either be liquids or gases. If a large heat transfer area is utilized, consisting of greater tube surface area, many tubes or circuits of tubes can be used concurrently in order to maximize the transfer of heat. There are many considerations to take into account in regards to the design of shell and tube heat exchangers, such as tube diameter, circuiting of the tubes, tube wall thickness, shell and tube operating pressure requirements, and more. In parallel fashion to a process control system, every decision made in reference to designing and practically applying the correct heat exchanger depends on the factors present in both the materials being regulated and the industrial purpose for which the equipment is going to be used.
The industrial and commercial applications of shell and tube heat exchangers are vast, ranging from small to very large capacities. They can serve as condensers, evaporators, heaters, or coolers. You will find them throughout almost every industry, and as a part of many large HVAC systems. Shell and tube heat exchangers, specifically, find applicability in many sub-industries related to food and beverage: brewery processes, juice, sauce, soup, syrup, oils, sugar, and others. Pure steam for WFI production is an application where special materials, like stainless steel, are employed for shell and tube units that transfer heat while maintaining isolation and purity of a highly controlled process fluid.
Shell and tube heat exchangers are rugged, efficient, and require little attention other than periodic inspection. Proper unit specification, selection, and installation contribute to longevity and solid performance.
Protection from cyber attacks and intrusions should be
a high priority wherever industrial automation is present
Industrial control system owners, operators, and other stakeholders should be aware of their exposure to malicious intrusion and attack by individuals or organizations intent on inflicting physical damage, stealing information, or generally wreaking havoc throughout an industrial operation. The risk of intrusion, regardless of the size or type of facility, is real and deserves the focused attention everyone involved in the design and operation of industrial control systems.
The National Cybersecurity and Communications Integration Center, part of the US Department of Homeland Security, ...
serves as a central location where a diverse set of partners involved in cybersecurity and communications protection coordinate and synchronize their efforts. NCCIC's partners include other government agencies, the private sector, and international entities. Working closely with its partners, NCCIC analyzes cybersecurity and communications information, shares timely and actionable information, and coordinates response, mitigation and recovery efforts. (from www.us-cert.gov/nccic)
The Industrial Control Systems Cyber Emergency Response Team (ICS-CERT) is a division under NCCIC. It has published a set of seven basic steps toward establishing a more secure industrial control system. I have included the publication below, and it is interesting and useful reading for all involved in industrial process control.
Having a fence around an industrial site, with a guarded entry gate, no longer provides the level of security needed for any industrial operation. Read the seven steps. Take other actions to build your knowledge and understanding of the risks and vulnerabilities. Cybersecurity is now another layer of design tenets and procedures that must be added to every control system. It will be a part of your company's best practices and success, now and in the future.
There are uncountable legacy controllers and communications devices throughout industrial America. All need to be reassessed for their vulnerability in the current and upcoming security environment. When reviewing your processes and equipment, do not hesitate to contact CTI-Controltech for assistance in your evaluation of our products.
Rotork, a global leader in valve automation, has introduced a new wireless valve position monitoring system that transmits real-time valve position indication to a central control location. The RI Wireless product line is certified Zone 1 Intrinsically Safe and intended for application in new and existing facilities in process industries and utilities.
In operation, each valve will have a Valve Monitoring Device (VMD) installed on the existing or new actuator using industry standard interfaces. The VMD gathers data from the actuator and transmits it across a network established using other routing hardware that is part of the total system. A software package provides the final connection to a receiving monitor or controller using industry standard connections.
There is more to be learned about the operation and benefits of the wireless valve monitoring system. The document included below provides description of the various devices that comprise the complete system, as well as the benefits that can be derived from its deployment. Reach out to a valve automation specialist and share your requirements and challenges. Combining your process knowledge with their product application expertise will produce effective solutions.
Every type of industrial control system is vulnerable
to some level of intrusion
Industrial control system owners, operators, and other stakeholders should be aware of their exposure to malicious intrusion and attack by individuals or organizations intent on inflicting physical damage, stealing information, or generally wreaking havoc throughout an industrial operation. The risk of intrusion, regardless of the size or type of facility, is real and deserves the focused attention everyone involved in the design and operation of industrial control systems.
The National Cybersecurity and Communications Integration Center, part of the US Department of Homeland Security, ...
serves as a central location where a diverse set of partners involved in cybersecurity and communications protection coordinate and synchronize their efforts. NCCIC's partners include other government agencies, the private sector, and international entities. Working closely with its partners, NCCIC analyzes cybersecurity and communications information, shares timely and actionable information, and coordinates response, mitigation and recovery efforts. (from www.us-cert.gov/nccic)
The NCCIC has published a set of seven basic steps toward establishing a more secure industrial control system. I have included the publication below, and it is interesting and useful reading for all involved in industrial process control.
Having a fence around an industrial site, with a guarded entry gate, no longer provides the level of security needed for any industrial operation. Read the seven steps. Take other actions to build your knowledge and understanding of the risks and vulnerabilities. Cybersecurity is now another layer of design tenets and procedures that must be added to every control system. It will be a part of your company's best practices and success, now and in the future.
There are uncountable legacy controllers and communications devices throughout industrial America. All need to be reassessed for their vulnerability in the current and upcoming security environment. When reviewing your processes and equipment, do not hesitate to contact CTI Controltech for assistance in your evaluation of our products.
Every industrial facility has a signature array of hazards
Industrial accidents range in severity and impact from minuscule to catastrophic. As operators, owners, or technicians involved with industrial operations, we all have a degree of moral, ethical, and legal responsibility to conduct our work in a manner that does not unduly endanger personnel, property, or the environment. Maintaining a diligent safety stance can be helped by reviewing industrial accidents at other facilities. There is much to learn from these unfortunate events, even when they happen in an industry that may seem somewhat removed from your own.
The U.S. Chemical Safety Board, or CSB, is an independent federal agency that investigates industrial chemical accidents. Below, find one of their video reenactments of an explosion that occurred in Texas in 2013, along with their findings regarding the cause of the incident. Check out the video and sharpen your senses to evaluate potential trouble spots in your own operation.
Contact CTI Controltech for any safety related information you may need concerning their lines of industrial process control and combustion products.
Brass Safety Valve - One of many types of safety valves
Danger and hazards are an integral part of industrial processes. The mitigation of these dangers and hazards, as well as reducing the probability of their occurrence, is the primary charge of industrial process engineering. Every product intended for use in a process control setting has safety and protection included in its design criteria. Pressure relief valves fall in that category of products designed and intended solely for safety purposes.
Manufacturers of what most generally refer to as pressure relief valves break the genre down into two distinct groups, relief valves and safety valves. One manufacturer, Anderson Greenwood (a Pentair brand), distinguishes the two valve types in their "Pentair Pressure Relief Valve Engineering Handbook"...
Relief Valve: A pressure relief valve characterized by gradual opening or closing generally proportional to the increase or decrease in pressure. It is normally used for incompressible fluids.
Safety Valve: A pressure relief valve characterized by rapid opening or closing and normally used to relieve compressible fluids.
The difference between the two valve types is found in their response to an excessive pressure condition. The relief valve, according to the definition, responds proportionally to the pressure increase, whereas the safety valve provides a non-proportional rapid response. Note also that the relief valve is generally intended for use with liquids (incompressible) and safety valves are commonly applied to compressible fluids, which would include steam and air.
Pressure relief valves are found anywhere pressure is contained, be it a piping system, vessel, even a household pressure cooker. The purpose of the relief or safety valve is to protect a pressurized system or vessel, should the system pressure exceed the maximum allowable working pressure. Simply put, keep it from breaking apart.
Because of the potentially catastrophic nature of a pressurized system failure, there is a high level of scrutiny, regulation, and testing focused on pressure relief and safety valves. The proper sizing and selection of the valves is also critical to providing proper function.
More detailed information, product data, and application assistance is available from the specialists at CTI Controltech.
Consider a generic industrial fluid process control operation. There are pumps, valves, and other components installed in the process lines that, due to their interior shape or their function, cause changes in the fluid motion. Let's look specifically at control valves and how their throttling operation can create conditions able to greatly impact the valve itself, as well as the overall process.
Fluid traversing a control valve can undergo an increase in velocity when passing the constriction presented by the valve trim. Exiting the trim, fluid then enters the widening area of the valve body immediately downstream with a decrease in velocity. This change in velocity corresponds to a change in the kinetic energy of the fluid molecules. In order that energy be conserved in a moving fluid stream, any increase in kinetic energy due to increased velocity will be accompanied by a complementary decrease in potential energy, usually in the form of fluid pressure. This means the fluid pressure will fall at the point of maximum constriction in the valve (the vena contracta, at the point where the trim throttles the flow) and rise again (or recover) downstream of the trim.
This is where cavitation begins.
If the fluid being throttled is a liquid, and the pressure at the vena contracta is less than the vapor pressure of the liquid at the flowing temperature, portions of the liquid will spontaneously vaporize. This is the phenomenon of flashing. If, subsequently, the pressure of the fluid recovers to a level greater than the vapor pressure of the liquid, any flashed vapor will rapidly condense, returning to liquid. This collapse of entrained vapor is called cavitation.
Flashing, the generation of vapor bubbles within the liquid, will precede and set the stage for cavitation. When the flashed vapor bubbles condense to liquid they often do so asymmetrically, with one side of the bubble collapsing before the rest of the bubble. This has the effect of translating the kinetic energy of the bubble’s collapse into a high-speed “jet” of liquid in the direction of the asymmetrical collapse. These liquid “microjets” have been experimentally measured at speeds up to 100 meters per second (over 320 feet per second). What is more, the pressure applied to the surface of control valve components in the path of these microjets can be intense. An individual microjet can impact the valve interior surfaces in a very focused manner, delivering a theoretical pressure pulse of up to 1500 newtons per square millimeter (1.5 giga-pascals, or about 220000 PSI) in water. In an operating fluid system, this process can be continuous, and is known to be a significant cause of erosive wear on metallic surfaces in process piping, valves, pumps and instruments. As the rapid change in pressure takes place, the bubbles (voids in the liquid) collapse (implode), and the surrounding metal surfaces are repeatedly stressed by these implosions and their subsequent shock waves.
Consequences for control valves, as well as for the entire control process, vary and are often destructive. They may include:
Loud noise
Strong vibrations in the affected sections of the fluid system
Choked flow caused by vapor formation
Change of fluid properties
Erosion of valve components
Premature destruction or failure of the control valve
Plant shutdown
The video provides a visual demonstration, through clear piping, of what happens inside the piping system when a valve is operated in a manner that causes substantial cavitation.
The solution lies in minimizing the potential for cavitation to occur through proper valve selection and sizing, along with coordinating operating characteristics of pressure drop inducing components with the total system performance. One valve manufacturer's recommendations are summed up in four basic approaches.
Avoidance of cavitation through proper valve selection. Use a valve with a rated liquid pressure recovery factor greater than that required for the application. Some applications may be suitable for the use of an orifice plate downstream of the valve.
Cavitation Tolerant Components capable of withstanding limited amounts of cavitation without excessive wear. Increased flow noise is likely to accompany this route.
Prevention of cavitation through the use of valve trim design that reduces pressure in several steps, avoiding excessive flashing. These valves can be expensive, but their effectiveness makes them an alternative worth considering.
Containment of the harmful effects of limited to moderate cavitation through trim designs that eliminate contact of the fluid with metal surfaces which are more susceptible to damage.
Share your requirements and application challenges with a valve specialist and gain insight through their recommendations. Combining your process knowledge with their product application expertise will yield a great solution.
Industrial control system pose special cybersecurity challenges.
The International Society of Automation is offering a free white paper entitled “What Executives Need to Know About Industrial Control Systems Cybersecurity”. The article provides useful commentary and information that establishes the scope of cybersecurity in the industrial process control space and provides a basic framework for understanding how every process may be impacted by lax cybersecurity efforts. The author, Joseph Weiss, differentiates Industrial Control System (ICS) cybersecurity from that of organizational IT through a review of various attributes common to both types, including message confidentiality, integrity, time criticality, and more. Any reader’s awareness and understanding of the cybersecurity risks to their operation will be enhanced through this article. I finished reading the article wanting more on the subject, and ISA is certainly a resource for additional content.
A quote from the article...
“Cyber incidents have been defined by the US National Institute of Standards and Technology (NIST) as occurrences that jeopardize the confidentiality, integrity, or availability (CIA) of an information system.”
ICS cybersecurity extends beyond preventing malicious outside intruders from gaining access. It is an important part of maintaining the overall operating integrity of industrial processes. A holistic approach is advocated to identify physical risk factors to the process and its componentry (previous post on device protection), as well as vulnerabilities that may prevent exploitation by unauthorized parties. Weiss goes on to describe the role and qualifications of the ICS Cybersecurity Expert, essentially an individual that can function effectively as an IT cybersecurity tech with the added skills of an industrial control systems expert.
A synopsis of attack events is provided in the article, with the author’s conclusion that not enough is being done to secure industrial control systems and the risk exposure is substantial in terms of potential threats to personnel, environment, and economy. By providing your name and email address, you can obtain the white paper from the ISA website. Your time spent obtaining and reading the article will be well spent.
For any specific information or recommendations regarding our products and cybersecurity, do not hesitate to contact us directly. We welcome any opportunity to help our customers meet their process control challenges.
Properly protect process measurement instrumentation to prevent mishap
The performance of every process is critical to something or someone. Keeping a process operating within specification requires measurement, and it requires some element of control. The devices we use to measure process variables, while necessary and critical in their own right, are also a possible source of failure for the process itself. Lose the output of your process instrumentation and you can incur substantial consequences ranging from minor to near catastrophic.
Just as your PLC or other master control system emulates decision patterns regarding the process, the measurement instrumentation functions as the sensory input array to that decision making device. Careful consideration when designing the instrumentation layout, as well as reviewing these five common sense recommendations will help you avoid instrument and process downtime.
Process generated extremes can make your device fail.
Search and plan for potential vibration, shock, temperature, pressure, or other excursions from the normal operating range that might result from normal or unexpected operation of the process equipment. Develop knowledge about what the possible process conditions might be, given the capabilities of the installed process machinery. Consult with instrument vendors about protective devices that can be installed to provide additional layers of protection for valuable instruments. Often, the protective devices are simple and relatively inexpensive.
Don't forget about the weather.
Certainly, if you have any part of the process installed outdoors, you need to be familiar with the range of possible weather conditions. Weather data is available for almost anywhere in the world, certainly in the developed world. Find out what the most extreme conditions have been at the installation site....ever. Planning and designing for improbable conditions, even adding a little headroom, can keep your process up when others may be down.
Keep in mind, also, that outdoor conditions can impact indoor conditions in buildings without climate control systems that maintain a steady state. This can be especially important when considering moisture content of the indoor air and potential for condensate to accumulate on instrument housings and electrical components. Extreme conditions of condensing atmospheric moisture can produce dripping water.
Know the security exposure of your devices.
With the prevalence of networked devices, consideration of who might commit acts of malice against the process or its stakeholders, and how they might go about it, should be an element of all project designs. A real or virtual intruder's ability to impact process operation through its measuring devices should be well understood. With that understanding, barriers can be put in place to detect or prevent any occurrences.
Physical contact hazards
Strike a balance between convenience and safety for measurement instrumentation. Access for calibration, maintenance, or observation are needed, but avoiding placement of devices in areas of human traffic can deliver good returns by reducing the probability of damage to the instruments. Everybody is trained, everybody is careful, but uncontrolled carts, dropped tools and boxes, and a host of other unexpected mishaps do happen from time to time, with the power to inject disorder into your world. Consider guards and physical barriers as additional layers of insurance.
Know moisture.
Electronics must be protected from harmful effects of moisture. Where there is air, there is usually moisture. Certain conditions related to weather or process operation may result in moisture laden air that can enter device enclosures. Guarding against the formation of condensate on electronics, and providing for the automatic discharge of any accumulated liquid is essential to avoiding failure. Many instrument enclosures are provided with a means to discharge moisture. Make sure installation instructions are followed and alterations are not made that inadvertently disable these functions.
Developing a thoughtful installation plan, along with reasonable maintenance, will result in an industrial process that is hardened against a long list of potential malfunctions. Discuss your application concerns with your instrument sales engineer. Their exposure to many different installations and applications, combined with your knowledge of the process and local conditions, will produce a positive outcome.
Example of switchbox containing limit switches and a
valve position indicator. Courtesy Flowserve/Automax
Limit switches are devices which respond to the occurrence of a process condition by changing their contact state. In the industrial control field, their applications and product variations are almost countless. Essentially, the purpose of a limit switch is to serve as a trigger, indicating that some design condition has been achieved. The device provides only an indication of the transition from one condition to another, with no additional information. For example, a limit switch triggered by the opening of a window can only deliver an indication that the window is open, not the degree to which it is open. Most often, the device will have an actuator that is positively activated only by the design condition and mechanically linked to a set of electrical contacts. It is uncommon, but not unknown, for limit switches to be electronic. Some are magnetically actuated, though most are electromechanical. This article will focus on limit switch designs and variants used in the control and actuation of industrial process valves.
Employed in a wide range of industrial applications and operating conditions, limit switches are known for their ease of installation, simple design, ruggedness, and reliability.
Valves, devices used for controlling flow, are motion based. The movable portions of valve trim create some degree of obstruction to media flow, providing regulation of the passage of the media through the valve. It is the movement of critical valve trim elements that limit switches are used to indicate or control. The movable valve trim elements commonly connect to a shaft or other linkage extending to the exterior of the valve body. Mounting electric, hydraulic, or pneumatic actuators to the shaft or linkage provides the operator a means to drive the mechanical connection, changing the orientation or position of the valve trim and regulating the media flow. Because of its positive connection to the valve trim, the position of the shaft or linkage is analogous to the trim position and can be used to indicate what is commonly referred to as “valve position”. Limit switches are easily applied to the valve shaft or linkage in a manner that can provide information or direct functional response to certain changes in valve position.
In industrial valve terms, a limit switch is a device containing one or more magnetic or electrical switches, operated by the rotational or linear movement of the valve.
What are basic informational elements that can be relayed to the control system by limit switches? Operators of an industrial process, for reasons of efficiency, safety, or coordination with other process steps, may need answers to the following basic questions about a process control valve:
Is the valve open?
Is the valve closed?
Is the valve opening position greater than “X”?
Has the valve actuator properly positioned the valve at or beyond a certain position?
Has the valve actuator driven the valve mechanism beyond its normal travel limits?
Is the actuator functioning or failing?
Partial or complete answers to these and other questions, in the form of electrical signals relayed by the limit switch, can serve as confirmation that a control system command has been executed. Such a confirmation signal can be used to trigger the start of the next action in a sequence of process steps or any of countless other useful monitoring and control operations.
Applying limit switches to industrial valve applications should include consideration of:
Information Points – Determine what indications are necessary or useful for the effective control and monitoring of valve operation. What, as an actual or virtual operator, do you want to know about the real time operational status of a valve that is remotely located. Schedule the information points in operational terms, not electrical switch terms.
Contacts – Plan and layout a schedule of logical switches that will provide the information the operator needs. You may not need a separate switch for each information point. In some cases, it may be possible to derive needed information by using logical combinations of switches utilized for other discrete functions.
Environment – Accommodate the local conditions and hazards where the switch is installed with a properly rated enclosure.
Signal – The switch rating for current and voltage must meet or exceed those of the signal being transmitted.
Duty Cycle – The cycling frequency must be considered when specifying the type of switch employed. Every switch design has a limited cycle life. Make sure your selection matches the intended operating frequency for the process.
Auxiliary Outputs – These are additional contact sets that share the actuation of the primary switch. They are used to transmit additional signals with specifications differing from the primary signal.
Other Actuator Accessories – Limit switches are often integrated into an accessory unit with other actuator accessories, most of which are related to valve position. A visual local indication of valve position is a common example.
Switches and indicators of valve position can usually be provided as part of a complete valve actuation package, provided by the valve manufacturer or a third party. It is recommended that spare contacts be put in place for future use, as incorporating additional contacts as part of the original actuation package incurs comparatively little additional cost.
Employing a properly configured valve automation package, with limit switches delivering valve status or position information to your control system, can yield operational and safety benefits for the life of the unit. Good advice is to consult with a valve automation specialist for effective recommendations on configuring your valve automation accessories to maximize the level of information and control.
Industrial process control valves are available in uncountable combinations of materials, types, and configurations. An initial step of
the selection procedure for a valve application should be choosing the valve
type, thus narrowing the selection field to a more manageable level. Valve
"types" can generally be classified by the closing mechanism of the valve.
A butterfly valve has a disc that is positioned in the fluid
flow path. It rotates around a central axis, the stem, through a 90 degree arc
from a position parallel to the flow direction (open) to perpendicular
(closed). A variety of materials are used in the valve body construction, and
it is common to line the valve with another material to provide special
properties accommodating particular process media.
What attributes might make a butterfly valve a beneficial selection
over another valve type?
The closure arrangement allows for a comparatively small
size and weight. This can reduce the cost, space, and support requirements for
the valve assembly.
Generally low torque requirements for valve operation allow
for manual operation, or automation with an array of electric, pneumatic, or
hydraulic actuators.
Low pressure drop associated with the closure mechanism. The
disc in the flow path is generally thin. In the fully open position, the disc
presents its narrow edge to the direction of flow.
Quarter turn operation allows for fast valve operation.
Some throttling capability is provided at partially open
positions.
Small parts count, low maintenance requirements.
What may be some reasons to consider other valve types?
Butterfly valve throttling capability is generally limited
to low pressure drop applications
Cavitation can be a concern.
Some sources mention the possibility of choked flow as a
concern under certain conditions.
Butterfly valves, like other valve types, have applications
where they outperform. Careful consideration and consultation with a valveexpert is a first step toward making a good selection. Combine your process know-how with the product application expertise of a professional sales engineer to produce the best solutions to your process control challenges.
Severe Service Industrial Control Valves Courtesy Flowserve - Kammer
Industrial process control applications can be associated with some very stringent and challenging performance requirements for the physical equipment and components that are part of the process chain. In fluid based operations, the control valves can be a point of significant impact of extreme fluid conditions, requiring careful design and selection consideration to assure proper performance and safety levels are maintained in a predictable way.
Industrial valves that are intended for application at the extremes are generally referred to as severe service valves. While there are plenty of published and accepted standards for industrial valves, one does not exist to precisely define a severe service valve.
So, how do you know when to focus valve selection activities on severe service valves, as opposed to general purpose valves?
There are a number of basic criteria that might point you in that direction:
Very extreme media or environmental temperature
High pressure drop operation that may cause cavitation
Rapid and extreme changes to inlet pressure
Certain types or amounts of solids contained in the fluid
Certainly, any of these criteria might be found in an application serviceable by a general purpose valve, but their presence should be an indicator that a closer assessment of the fluid conditions and commensurate valve requirements is in order. The key element for a process stakeholder is to recognize when conditions are in evidence that might overrun the capabilities of a general purpose valve, leading to premature failure in control performance or catastrophic failure that produces an unsafe condition. Once the possibility of a severe service condition is identified, a careful analysis of the possible operating conditions will reveal the performance requirements for the valve.
There are numerous manufacturers of severe service valves, each seeming to concentrate on a particular niche. Kammer, a brand in the Flowserve family, has an interesting approach to accommodating the highly varied requirements of severe service applications. Their product line consists of a number of standard configurations, but also includes semi-modular components that can be combined to meet the many custom requirements of severe service applications.
I have included a technical bulletin (you know it's technical when it's not in color) that describes and nicely illustrates how the company employs various interchangeable body styles and packings with their multi-stage plug to meet a wide range of severe service challenges. Browse the bulletin, as it has some good cutaway views of valve interiors.
You can always get more information, or discuss your special requirements, with a product application specialist. They have access to technical resources that can help with selecting the right valve components to meet your severe service applications.
Vibrating Tuning Fork Level Switch Courtesy Clark Reliance - Jerguson
Tuning forks,when combined with appropriate electronics, can be used in the industrial process control field as liquid level switches. This simple, all solid state device can be a cost effective solution to wide ranging requirements for single point level detection. This type of level switch is designed using the principles of a tuning fork. Piezo-electric crystals induce fork oscillation at a fundamental frequency. Employed as a high level indicator or alarm, the forks vibrate in air until the liquid level rises and covers the forks. The liquid measurably dampens the fork vibration frequency when it covers the sensor. The level switch electronics detect the frequency shift and change the state of a relay to provide an indication of the change. A variety of output options can provide on/off load switching or a direct interface with a PLC. Use the level detectors as high or low level switches with proper configuration. A primary advantage of the vibrating tuning fork level switch is its all solid state design. There are no floats or other mechanical linkages. It is also generally unaffected by flow, bubbles, foam, vibration, or solids content. They can also be installed in any orientation. Variants are available for special installations that may require hygienic fittings or explosion proof housings. Explore these level switches for your applications. Share you requirements with a product specialist and attain the best solution.
Industrial Water Tube Boiler Courtesy Victory Energy
CTI-Controltech represents Victory Energy Operations in California. The company designs, engineers, manufactures and services heat recovery steam generators, industrial boilers, fired packaged boilers, waste heat boilers and related equipment. Target markets include power generation, bio-renewable, oil sands, petrochemical, district heating, education and healthcare. Victory Energy also offers mobile/rental boilers, auxiliary equipment such as economizers, deaerators and stacks. Services include full-time aftermarket field services and aftermarket spare parts.
Victory is a full service provider, from design and manufacturing to service and repair. Learn about this truly 21st century company from the video included below. You can always contact the industrial control and combustion specialists at CTI Controltech for solutions to your combustion, steam, and other HVAC challenges.
Rotork IQ3 Electric Valve Actuators, a product line handled by CTI Controltech, offer some innovative improvements that provide industrial process operators higher levels of reliability, accessibility, and security than previously available. Among the strong features of this product:
Advanced Display (detailed in the video below)
Asset Management
Bluetooth Communications Interface
Compact Double-Sealed Enclosure
Absolute Encoder (on some variants)
Intelligent Battery Management
Local Interface
Secure Local Controls
Watertight, Dust Tight, Explosion Proof
There is plenty of detail available about all the features of the solidly built IQ3 line of actuators for industrial process valve control. Watch the video and contact a product specialist to get more detail or assess your specific application needs.
Electric Power Plant One of many industries served by CTi Controltech
CTi Controltech is a San Ramon, California based engineering contractor and distributor specializing in industrial process control and combustion. The company combines engineering, field services, and quality hardware to provide value-engineered solutions for projects involving combustion and industrial process control. CTi approaches each application challenge by analyzing specific performance requirements, along with customer growth plans and budgets, to formulate the best solution. In some cases, multi-year strategies have been developed to ensure the proposed solution contributes to the customer's desired outcome.
CTi Controltech was founded in 1976 by Art von Wronksi and Allan Zensius, both of whom had extensive burner/boiler and industrial controls experience. Together they built the company, achieving a regionally recognized leadership position in the combustion controls industry. Since 2002, George Constas has owned and operated CTi Controltech, drawing on his many years of process control industry and executive experience. Today CTi’s expertise has expanded beyond its original focus on burner management and combustion control into other areas of process control in industries such as; Refining, Power (including renewable such as Geothermal and Solar), Food, Specialty Chemicals, Mining, Semi-conductor, and OEMs. CTi Controltech maintains a staff of engineers, technicians, and sales/support personnel to provide technical assistance, field service, engineering, and order processing.
A good company with a long successful history. Learn more about CTi Controltech. View their product line card below and bring them in for a consultative discussion on your next project of any size.
Industrial process measurement and control entails projects, lots of projects. Equipment and instruments that are the life of our processes periodically need modification, replacement, major service or maintenance. Large scale work is generally contracted out for a variety of reasons, not the least of which is that the manpower, equipment, or license and certification requirements are beyond what the stakeholder (the company) may possess . But on smaller projects, an organization is often confronted with the decision of whether to do the work in house or contract it out. There are potential perils and rewards, regardless of the path you take.
Do your project work in-house or contract it out?
I'm a guest writer on this blog, sharing my personal opinion on the subject. As additional disclosure, I share with you that the host of this blog, CTI Controltech, supports in-house project work by their customers with consulting, advice, and the provision of parts and equipment that they sell. The company also provides construction, engineering, and field services, making them a supporter of both in-house and contracted efforts by their customers.
The title of this article reveals my leanings on the issue of whether to outsource. Based upon my own project experience and observations of others in their pursuit of project completion, I am generally in favor of it.
With my bias exposed, prior to determining whether to use internal or external resources, still take the time to document some elemental project requirements.
What is the starting condition of the project? It is important to systematically assess the existing conditions, as they have a substantive impact on the scope of work needed to be accomplished to reach the point of completion.
What is to be the ending condition of the project, the definition of "completion"? There must be a defined ending condition that, once achieved, signals that the project is complete. Start with a general statement and add details garnered from various stakeholders. Keep in mind that the end condition will need to satisfy all stakeholders, so their input should be influential.
How much time is allowed to complete the work? This pertains to the needs of the company, not the time required to accomplish the task. If there is a deadline for the project, it must be known. An example would be completion of combustion efficiency upgrades prior to the effective date for a new emissions standard. It's not when the work can be done, but when it must be done
How much time will be required to complete the work? This may be difficult to ascertain at project inception, but some allowance should be assigned to planning, equipment and material procurement, actual hands-on trade and technical work, startup, testing, commissioning, and final documentation and training. This exercise will help you develop a more detailed picture of what is involved in getting the project completed and how long the timeline might be.
What special trade or technical skills will be required? You may need skilled or certified individuals to perform certain tasks. It is essential to know these resource requirements.
Does any of the work require a license or permit? Some extents of modification may require permits from a local jurisdiction and/or licensed trades to perform the work. New work often requires permits. Every jurisdiction has its own set of standards and requirements which must be considered.
Recall that I said "document" the project requirements. This is important for everyone involved. You want to prevent the "drifting" of performance benchmarks during the course of the project. This should be especially important if you are the one responsible for project completion. Injections of additional requirements midstream have the potential to destroy your carefully considered plans and result in delays, compromised quality, and dissatisfied stakeholders. If somebody wants a change, insist that they be realistic about its impact on the schedule.
There are three major decision factors to consider for in-house or outsourced projects?
Technical resources: Do you have people on staff with skills and qualifications that match those that will be needed to accomplish all the tasks comprising the project? That may include substantially more than the mechanics needed to install newly acquired parts and equipment. Consider engineering and design, the production of required documentation, procurement and scheduling of materials and equipment, proactive scheduling and coordination of the various tasks, and general project management.
Special equipment and tools: Are there any particular tools, instruments, or equipment that will be required on the project? Does the organization have these resources on hand? If not, how will they be procured, how long does it take, how much does it cost?
Available manpower: Are there enough personnel in the organization with the needed skills to complete the work AND is there enough slack available in their schedule to allow a sufficient amount of their time to be devoted to the project to achieve a timely completion? This is critical and applies to both the skilled trade labor and administrative manpower requirements.
An honest and thoughtful consideration of the three areas outlined will likely convince you that, unless the project is small in scale and simple in scope, outsourcing to a contractor with expertise and experience in the work to be accomplished is your best course of action. Sure, dealing with contractors can be difficult and merely outsourcing will not be a panacea for all the challenges presented by any project. However, if a contractor's responses to the three considerations outlined above are better than yours, there is probably advantage in hiring them.
In the big picture, outsourcing can keep your company's resources available to perform more directly related to revenue generation, which is what they were likely hired for in the first place. Outsourcing draws comparatively little from the organization resource pool and, candidly, puts the bulk of the performance burden and the associated aggravation and stress on another organization that is probably better equipped to handled it than you. Done right, it can be a big win for everyone.
Severe Service Ball Valve Section View Courtesy Mogas Industries
Industrial process control, as a field of endeavor, can expose an engineer to instances where their design input can have very significant impact on the financial prospects of their employer, even the safety and well being of the public residing near company facilities. "Getting things right the first time" is much more than a motivating slogan on a poster tacked to the wall in the corridor outside the engineering department. It is what our society demands of engineers. Fortunately, there are engineers that embrace the role of making sure things go as planned. They work as process engineers and also as designers of the componentry and equipment used to implement complex and potentially dangerous processes.
I have written about the positive and potentially not so positive attributes of ball valvesfor industrial process control applications. In that recent blog article, I mentioned that ...
"There may be particular ball valve variants that overcome potential shortcomings listed in this article". Ball valves designed for severe service are an example of a manufacturer specifically designing ball valves to not only overcome some potential shortcomings of the valve type, but to extend the performance ratings into areas that accommodate some of the most demanding applications in the process control field.
What constitutes severe service?
Extreme temperatures
High pressures
Abrasive particulates
Acidic products
Heavy solids build up
Critical plant safety
Large pressure differentials
Velocity control
Noise control
Extended or enhanced features of severe service ball valves include:
Floating or trunnion mounted ball design with straight through bore path that protects the sealing surfaces.
Wide seat sealing surface with matched ball and seat sets that provide total sealing contact for reliable isolation. The greater sealing contact area withstands minor scratches and abrasions.
Independent replaceable seats to minimize repair and maintenance costs.
Pressure energized sealing, with seat springs that maintain a constant sealing contact between the ball and seats. Metal seats wipe the ball sealing surface clean during every operation.
Blowout proof one piece oversized stem design meets stringent industrial safety standards and withstands maximum working pressures and extreme service torques.
Dual-guided stem design employs pressure energized inner stem seals as a thrust bearing and lower stem guide. The valve stem bushing serves as the upper stem guide to eliminate lateral movement of the stem and prevent media migration and fugitive emissions.
Greater body wall thickness, with forged body and end connections for longest service life.
A heavy duty operator mounting flange, to provide structural support for the valve operator, is machined after attachment to assure precise stem alignment.
Application specific features, such as seat designs, live loaded packing, body gaskets, coatings, liners, purge ports, end connections, and special materials are also available to customize these severe service valves to meet extreme application requirements. The presentation below provides schematic and illustrated examples where severe service valves are applied and provides additional detail about the special features incorporated in the design of severe service ball valves. For all your control or isolation valve projects, whether in the conceptual, planning or implementation stage, consult a valve specialist. Merge your grasp of the process and its requirements with the product knowledge and application experience of a specialist and produce a solidly positive project outcome.
We, as engineers, industrial process operators and stakeholders, recognize the necessity and value of a continuous stream of accurate and timely information about our processes. Our experience has also taught us that the environment and activities surrounding our installations can have a significant impact upon our ability to continually gather accurate process measurements. Some of our concerns include:
Weather - An element whose impact cannot be understated....or easily predicted.
Physical Contact - Equipment and measurement devices must be protected from damaging impact.
Security - Vandalism, cyber invasion, and other external threats are possible
Our responsibility, as operators of machines and handlers of materials that can produce hazardous or life threatening conditions in the case of failure or error, is to foresee every reasonably probable event that could adversely impact the safe and proper operation of our industrial processes.
One manufacturer has developed an innovative solution to a potential problem in the application of magnetic level controls.
The short video below outlines the source of the potential failure and the way in which the product design change successfully overcomes a potentially adverse impact on process measurement. Invest less than three minutes of your time to watch the video and build your application knowledge by learning from the experience of others. Do not hesitate to contact a product application specialist for more detail, or to discuss your process measurement needs.
Cutaway View of Industrial Ball Valve Courtesy of Flowserve Atomac
Industrial fluid handling and process control rely on valves to regulate the pressure and control the flow rate and direction of a wide variety of liquids and gases. There can be highly sensitive or specialized performance requirements, along with additional needs for corrosion resistance and an ability to withstand extreme fluid or environmental temperatures. Selecting the proper valve can be a challenging and time consuming operation for a new or updated process. Taking an initial step of narrowing the field of potential candidates to those with basic operational and construction characteristics that will be advantageous to your process requirements will move you quickly toward an effective selection.
Industrial valves for flow control are often grouped and referred to by their closure mechanisms. Common types include ball, plug, butterfly, globe, and gate. Each type has attributes making it more suitable to certain applications. Start your selection process by choosing a valve type that will provide the type of service needed. Let’s look at ball valves.
Ball valves are named for the generally spherical shaped element encased in the valve body and placed directly in the fluid flow path. The ball has a hole, or port, through it’s center that allows fluid to pass when the port is aligned with the direction of flow. The stem, attached to the ball and extending to the exterior of the valve body, that can be rotated through a 90 degree arc manually, or utilizing a powered actuator. At one extreme of the arc, the port is perpendicular to the flow path and fluid flow is completely obstructed and shut off. Rotating the stem ninety degrees from the closed position will align the port with the flow direction in the fully open position.
What are some potential advantages of ball valves?
Interior of Ball Valve Courtesy of Mogas Industries
Well suited for applications requiring either full flow or no flow.
Quarter turn operation provides a rapid transition from open to closed position.
Leak-proof service.
Force required to drive the valve stem is comparatively moderate.
No lubrication required and maintenance is minimal.
Comparatively light weight and compact, reduced installation space and support requirements.
When fully open, the port provides little resistance to flow with a straight through path.
What are some potentially concerning attributes?
Residual amounts of the process fluid may be trapped in the port when the valve is closed, then released to the fluid stream when the valve is opened. Potential contamination impact should be considered.
Ball valves are not well suited for throttling of the flow. Partially open ball valves expose seals and sealing surfaces to effects of the fluid velocity and potentially corrosive nature of the fluid. Additionally, the basic construction and operation of the ball and port generally do not provide variable flow control as well as some other valve types.
Valve seals, most often elastomertic materials, may not be compatible with fluid characteristics. Consider temperature, corrosiveness, and other fluid characteristics for compatibility with the seal material.
These general points are intended to get you thinking about your valve application in a productive and efficient manner. There may be particular ball valve variants that overcome potential shortcomings listed in this article. Talk to a valve specialist about your application. Their recommendation, based upon high level product knowledge and experience with numerous applications, will be a valuable addition to your decision making.
