Showing posts with label Montana. Show all posts
Showing posts with label Montana. Show all posts

Friday, February 23, 2018

Industrial Diaphragm Valves

sectional drawing weir type diaphragm valve with pneumatic actuator
Section drawing of diaphragm valve, weir type,
with pneumatic actuator.
Image courtesy Gemu Valves, Inc.
Diaphragm valves are named for the means employed in their design to restrict the path of fluid flow through the valve. Most valve designs employ a rigid solid shape which is repositioned in the fluid path to regulate flow. Diaphragm valves are somewhat unique in their use of a flexible material that is deformed by a moving part connected to the valve operating mechanism. The diaphragm acts as the flow restrictor and seat. It also isolates the valve bonnet and stem from the flowing media.

The fluid path and diaphragm positioning and seating enable this valve type to be used for throttling or simple stop operations. They are generally tolerant of particulate matter entrained in the media. Selecting body and diaphragm materials that are compatible with the media are primary elements of achieving a successful application. The diaphragm is a wearing part and should be inspected periodically and replaced when necessary.

Diaphragm valves for industrial use are available in a range of materials and sizes to accommodate light through heavy duty applications.
  • Suitable for inert and corrosive liquid and gaseous media when proper valve body and diaphragm materials are selected
  • Bonnet and valve bodies available in metal or plastic construction
  • Insensitive to particulate media
  • Valve body and diaphragm available in various materials and designs
  • Compact design
  • Automation via pneumatic or electric means
Share your fluid process control challenges with valve application specialists. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.

Sunday, February 18, 2018

Getting Benefit From Waste Steam With a Thermocompressor

steam thermocompressor
Steam thermocompressor enables use of waste steam
in higher pressure applications.
Image courtesy Spirax Sarco
Steam, with its utilization as a means of transferring heat, as well as a motive force, is found in use throughout many industries. The production of steam is a significant cost of operation for any business where it is employed. Steam, after performing its intended function, still contains a comparatively large amount of heat, so methods of recovering or utilizing that heat energy remaining in waste steam is a positive step in conservation.

Energy conservation and energy efficiency have contributed very large cost savings to many industrial and commercial operations over the past two decades. Projects with modest payback periods quickly contribute to the bottom line of the operation's balance sheet. It is not uncommon for  energy conservation and efficiency measures contribute to improvement in the overall functioning of the steam utilization equipment or systems. In order to save energy, it is generally necessary to exercise better control over equipment or system operation by gathering more information about the current operating state. This additional information, gathered through measurement instrumentation, often finds use in several ways that improve productivity and performance.

A thermocompressor is a type of ejector that mixes high pressure steam with a lower pressure steam flow, creating a usable discharge steam source and conserving, through reuse, the remaining heat content of the otherwise wasted low pressure steam. The device is compact and simple, with no moving parts or special maintenance requirements. Two general varieties are available. A fixed nozzle style is intended for applications with minimal variation in the supply and condition of the suction steam (the low pressure steam). Some control is achievable through the regulation of the high pressure steam flow with an external control valve. A second style provides a means of regulating the cross sectional area through which the high pressure steam flows in the nozzle. This style is best applied when specific discharge flow or pressure is required, or there is significant variation in the inlet steam conditions.

Share your steam system challenges with a steam system application specialist. Leverage your own process and facilities knowledge and experience with their product application expertise to develop effective solutions.


Wednesday, February 7, 2018

Plug Valves - Right For Your Application?

industrial plug valve with manual operating handle
Plug valves incorporate design features making them
a positive choice for many fluid process applications.
Image courtesy Fluoroseal, Inc.
There are common components to be found on almost every process system that involves fluid control. Regardless of the operation's scale, pumps, piping, tanks and valves are likely to be part of the system.

Valves, of which there are many types, provide control over the flow rate, direction and routing of fluids in a processing operation. Flow can be started, stopped or modulated between zero and full rate using a properly sized and configured valve. Some valves enable media flow to be diverted to a selection of outlets, in lieu of a single inlet and outlet pair. Specialized valves regulate inlet or outlet pressure, or prevent fluid flow from going in an undesirable direction. All of these capabilities are packaged into differing valve product offerings that present a very large selection array to a process designer or engineer.

Industrial flow control valve types are generally classified according to the structure or arrangement contained within the valve body that provides obstruction to fluid flow. Some of the common types are ball, butterfly, gate, globe, and plug. Surely, there are more valve types, and this article is not intended to list them all. Some of our previous blogs have discussed selection considerations for gate, ball and butterfly valves. This article will focus on one of the oldest valve types, the plug valve.

Plug valves, like ball and butterfly valves, span from fully open to fully closed positions with a shaft rotation of 90 degrees. The “plug” in a plug valve is installed in the flow path within the valve body and rotated by means of a stem or shaft extending to the exterior of the body. Plugs are often tapered toward the bottom and are fitted to a seating surface in the valve body cavity that prevents fluid from bypassing the plug. An opening through the plug, the port, can be shaped to provide particular flow characteristics. There are numerous variants of the basic plug valve which may make it suitable for particular applications. One common variant is the lined or sleeved plug valve, with an insert or interior lining of material that creates an isolating barrier between the valve body and the media. This allows use of less expensive materials for the body construction that may be otherwise subject to corrosion by exposure to aggressive media.

Positive attributes of plug valves.

  • 90 degree rotation from open to closed provides fast operation.
  • With proper configuration, can be well suited for frequent operation.
  • Availability of corrosion resistant liner may provide comparative cost savings because valve body can be constructed of less expensive material.
  • Design is simple and employs a low parts count.
  • Valve can be serviced in place.
  • Generally, low resistance to flow when fully open.
  • Reliable leak-tight service due to tapered plug wedging action, replaceable sleeve, and injection of lubricant in some variants.

Potential issues of concern.

  • Higher friction in the plug closure mechanism may require comparatively higher operating torque than other valve types.
  • Without a specially designed plug, generally not well suited for throttling applications.
  • Rapid shutoff delivered by plug design may not be suitable for some applications where hammering may occur.

Share your fluid control application challenges with a valve and automation specialist. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.

Friday, February 2, 2018

Pressure and Temperature Switches for Rugged Industrial Applications

adjustable pressure switch
This adjustable pressure switch is one of many variants
available to suit every application.
Image courtesy Custom Control Sensors (CCS)
Matching up the most appropriate control device for a processing application, taking all factors into account, may not always result in a selection of the most technologically advanced, complex or full featured solution. Sometimes, all that is needed is a device with a limited performance set, but one that performs its functions reliably in a challenging industrial environment.

Industrial versions of temperature, pressure and differential pressure switches are fitted with appropriate mountings for the process and housings for the installation environment. Hazardous location installation can be accommodated. High current switch ratings and auxiliary functions add to the usefulness of these devices. There are almost countless variants available to accommodate almost every application. Don’t overlook these simple and reliable mechanical devices as candidates for application in temperature and pressure control. Share your application requirements and challenges with product specialists for useful recommendations.



Thursday, January 25, 2018

Krombach Brand Valves for Rugged Service Conditions

metal seated butterfly valve with actuator
Metal seated butterfly valves for aggressive process
applications are a hallmark of the Krombach brand.
Image courtesy Crane CPE
The Krombach branded valves, part of the Crane CPE product offering, target challenging applications in industrial settings that benefit from the use of valves specially designed for severe service. The brand also includes a standard product offering of valves and specialties for a broad range of common industrial applications.

The Krombach line includes:

  • Butterfly Valves - High performance, resilient seated, double-eccentric, triple offset and special purpose butterfly valves.
  • Ball Valves - Process one-piece, two-piece and three-piece, metal seated, soft seated and compact ball valves.
  • Globe and Angle Valves - Bronze, cast iron, cast steel and stainless steel globe and angle valves.
  • Gate Valves - Bronze, cast iron, cast steel and stainless steel gate valves.
  • Check Valves - Ball, dual-plate, foot, full body swing, steam stop, tilting disc, wafer style swing, nozzle-type and pressure seal check valves.
  • Vacuum Relief Valves - Available with flanged or threaded connections.
  • Aerating and Deaerating Valves - Essential for trouble-free operation of pipeline systems handling liquids.
  • Float Valves - Single seated and double seated versions for a variety of applications.
  • Throttle Valves - Available with flange connection, wafer- or weld-in type.
  • Bottom Drain Valves - Available manually operated or with a diaphragm actuator.

Below is a cutsheet providing an overview of the company's standard product categories. Whatever your fluid control application, share your challenges with the valve specialists at MSEC. Leverage your own process knowledge and experience with their product application expertise to develop effective valve and automation solutions.


Thursday, January 18, 2018

Corrosion Resistant Cooling Towers

corrosion resistant HDPE cooling tower
One variant of corrosion resistant cooling tower
Image courtesy Delta Cooling Towers
Cooling towers rank highly as included components of heat rejection systems. Building and facility HVAC and industrial process cooling commonly rely on cooling towers as the final phase of transferring heat from inside a system, such as a building, to the outdoor environment. With most relying on the evaporation of water as the means to efficiently move large amounts of heat, cooling towers contain large wetted surfaces in almost continuous contact with solutions of water and various chemicals used to maintain certain fluid conditions. The heat transfer solutions can be aggressive, and many towers are constructed using metal for the wetted parts and case of the unit. This has traditionally been an area of concern with cooling tower ownership, since the combined elements of water, treatment chemicals, and time take their inevitable toll on the equipment.

Avoiding the deterioration of metal clad cooling towers is construction utilizing high-density polyethylene (HDPE). HDPE is not impacted by water, treatment chemicals, or elements often present in the air, whether harsh chemical vapors emitted from nearby industrial plants or natural corrosives such as salt air.

Delta Cooling Towers, Inc., based in New Jersey, USA, manufactures HDPE cooling towers and possesses an extensive portfolio of completed successful applications utilizing HDPE construction features. Below is a short case study showing how one industrial user benefited from installing HDPE cooling towers.

Read the case study and get more information from an application specialist. See how incorporating HDPE cooling towers into your operation can reduce maintenance burden and lead to longer machinery life.

In any business venture or other organization, relying on doing things the way they have always been done can be detrimental to real progress and improvement. Incorporating change involves risk, but good planning and careful analysis will increase the probability of success.


Wednesday, January 10, 2018

Steam Trap For Heavily Contaminated Steam

cast iron float steam trap
The Float Trap series is available in carbon or stainless steel.
Image courtesy Spirax Sarco
Industrial process gear and equipment manufacturers are always tweaking designs, adding features, and creating new product variants in response to the challenges presented by the immeasurably broad range of application and operation scenarios for their products. Spirax Sarco is a globally recognized leader in the design and manufacture of steam system specialties, and has created a rugged steam trap to accommodate some tough challenges.

The company's FTC23 and FTS23 Float Trap products are ball float steam traps suitable for use with saturated and superheated steam. The units can be utilized on process equipment and for drainage of temperature controlled systems. These traps are specifically targeted at applications involving steam that may be carrying solids or incondensable gasses. Solids, if not purged from the system, can accumulate and foul the internal trap mechanism, leading to failure.

The company indicates that the main design feature is a self-cleaning float closing mechanism which maintains safe operation even in the presence of severe contamination. The positioning of the valve and seat also promote the discharge of the condensate, along with entrained contaminants. There is even a manual lever on the exterior of the trap that allows an operator to force the full opening of the valve, regardless of whether condensate is present. This operation facilitates fast removal of contaminants and maintains optimum performance.

The two models differ in their construction materials, with one having a carbon steel body, the other a stainless steel body. Internals are stainless steel on both units.

Share your challenges with the steam system specialists, leveraging your own knowledge and experience with their product application expertise.


Friday, January 5, 2018

Piston Isolation Valves For Steam and Condensate

carbon steel or stainless steel piston valve for steam or condensate
Simple and reliable piston isolation valve is well suited
for steam and condensate applications.
Image courtesy Spirax Sarco
Piston valves are serviceable and reliable valves that are well applied to isolation use in steam and condensate systems. Recently, Spirax Sarco, globally recognized manfacturer of steam system componentry, introduced their PV4 and PV6 lines of piston isolation valves targeted at steam and condensate applications.

The new valves are available with carbon steel or stainless steel bodies, with the internals of both being stainless steel. Screwed, socket weld and butt weld connections are available in 1/2" through 2" sizes. The operation is unidirectional, so installation must have the system flow according to the arrow on the body. The only other installation restriction is that the handwheel should be above the valve body.

Accommodated pressure and temperature ranges for the PV4 and PV6 will be suitable for a broad range of steam and condensate applications. Share your steam system challenges of all types with application specialists. Leverage your own knowledge and experience with their product application expertise to develop effective solutions.


Thursday, December 21, 2017

Capsule Steam Traps

cutaway view capsule steam trap
Capsule type steam trap, cutaway view
Image courtesy Tunstall Corporation
Steam traps are an important part of a closed steam system, directing condensate on a path back to the boiler for reuse and venting non-condensing gases from the system. Of the several different types of steam traps utilized commercially, the thermostatic steam trap is but one. Thermostatic traps are often applied when the application can benefit from a utilization of some of the heat remaining in the condensate. This trap design will hold the condensate in place until it cools sufficiently below the saturation temperature of the steam.

Capsules utilized in thermostatic steam traps contain the controlling elements of the device. The parts are somewhat subject to wear through their movement, but more so from the corrosive effects of system fluid, impurities, and mechanical shock from water hammer. Tunstall Corporation specializes in the manufacture of replacement capsules for thermostatic steam traps that provide better service and extended warranty duration. Their sealed units are fabricated of stainless steel and welded to seal out deterioration due to exposure to steam and condensate. Drop in replacement capsules are available for conceivably every trap manufactured in the previous few decades.

Share your steam system requirements and challenges with application specialists, leveraging your own knowledge and experience with their product application expertise to develop an effective solution.

Wednesday, December 13, 2017

Process Tuning

sliding gate industrial process control valve
This sliding gate industrial control valve could operate
under the command of a tuned process control loop.
Image courtesy Schubert & Salzer
Controller tuning is a process whereby a controlling device in a process has a response characterized to the needs of maintaining a process condition within certain limits under a range of varying disturbances to the process. Established guidelines for automation standards exist so that every process control operator can experience the same standard of safety and maintenance in a way universally understandable. The International Society of Automation (ISA) promotes different tuning standards based on the particulars of the control process, such as temperature or liquid level control.

Liquid-level control loops are usually considered non-self-regulating processes. They require external moderation to remain uniform and for errors to either be mitigated or corrected. General rules which exist for adjusting and tuning loops for self-regulating process, such as temperature control, are often inapplicable to liquid level loops, making liquid level control loops somewhat unique in their tuning.

In order to address the counter intuitive nature of these process loops, start with a model of the loop’s ideal functionality. This can serve as a reference. After doing so, incorporate potential variables into the ideal loop and evaluate their impact on the model process. Checking equipment, then modeling the process dynamics, allows engineers to observe the manner in which the process reacts in relation to the target or goal performance.

Whereas other loops can be tuned via trial and error, liquid-level control loops should not be due to the nature of their reactions to controller input being different than that of other processes. Instead, the parameters for the control loop need to be carefully engineered, rather than specifically tuned. Liquid level loops are integrating processes, rather than self-regulating. A self-regulating process will, with no disturbances to the variables, reach an equilibrium at which the process value remains constant. Consider a non-self-regulating liquid level control loop where the fill valve is open. No equilibrium point will be achieved, just overflow. The distinction between the two types is key to understanding why tuning liquid level loops is a different process than self-regulating control loops.

Temperature and thermal loops, depending upon the process dynamics, present varying degrees of tuning challenge. PID temperature controllers are employed to adjust the heat input to a process to affect a change in, or maintenance of, a process temperature setpoint. Without proper tuning, the controller output and the resulting process performance can oscillate or be slow to respond, with a negative impact on process performance or yield. Many PID controllers have an auto-tune feature, some of which are more effective than others. The best results achievable by PID controller tuning are accomplished by defining a setpoint prior to the auto-tune process and starting the tuning procedure from a stable process condition. Tuning the controller in the same process environment in which it will operate can also be very helpful.

Share your process measurement and control challenges with experienced application specialists, combining your own knowledge and experience with their product application expertise to develop effective solutions.

Thursday, December 7, 2017

Compressed Air as a Motive Force

coalescing filters for compressed air
Coalescing filters are common components of a compressed
air system.
Image courtesy SPX Pneumatic Products
Compressed air is utilized throughout every industry and many commercial settings. While primarily used as a motive force, compressed air serves as a utility in many applications in the oil and gas, chemical and petrochemical, nuclear power, food, pharmaceutical, and automotive industries. The presence and use of compressed air across multiple industries is so essential, its importance is comparable to utilities like electricity, gas, and water.

In the control of fluid processes, compresses air facilitates operation and control of valves and other instruments. Dry air, with a sufficiently depressed dew point, can ensure process materials and equipment stay free of moisture and its associated impediments to smooth operation. The use of compressed air as either a motive force or a utility imparts minimum requirements on its quality or constituents. Confounding substances, such as particulates, water, and oil, may be entrained or contained in a compressed air stream. Various methods of filtration and moisture removal may be necessary to condition or process the compressed air in order to deliver consistent quality.

The advantages of using compressed air as a motive force in industrial settings are more numerous than appropriate for listing here, but consider that tools driven by compressed air can be more compact, lower weight and less prone to overheating than electrically driven tools. Air driven devices tend to have reduced parts count and require little maintenance, whether tools, valve actuators, pistons, or other machines. Compressed air driven devices can be fashioned to amplify the power of an electrical signal, enabling a simpler means of powering some types of loads. Compressed air, by its nature, presents no electrical hazards to the workplace.

Whenever air driven devices are utilized, attention must be given to compressed air production. The pressure, maximum flow rate demand, and compressed air quality must meet the process or operation requirements. Share your compressed air system challenges with specialists, leveraging your own knowledge and experience with their product application expertise to develop effective solutions.

Tuesday, November 28, 2017

Pipeline Cyber Security

binary stream representing industrial process control network data transfer and cyber security threat
Cybersecurity is a process control challenge that consistently evolves as new technologies come into use and new threats emerge. Since process control methods are constantly developing, the protective measures need to match the rate of change to ensure adequate levels of protection are in place. Pipelines used in the oil and gas industry, as well as in the transportation of a multitude of liquid and gaseous products, account for more than 2.3 million miles of process piping in the United States.  Natural gas pipelines are commonly monitored and controlled by, for example, programmable logic controllers or other microprocessor and communications based systems, responsible for flow regulation and various process conditions. Because of the prevalence of these systems, they are a target of increasing attacks, on both PLCs and other SCADA related devices, such as compressors, remote terminal units, communication networks, and other critical process infrastructure elements.

While developments in technology have provided operating advantages and improvements to the process industries, the more complex and advanced the systems may also increase the exposure to malicious penetration and mischief by unauthorized parties (hackers). Because of this, diligence by industry professionals, while always a strong component of protecting against outside threats, has been augmented via new guidelines meant to better prepare all process operators against more coordinated cyber-attacks.

Basic preventative measures, such as a firewall, are no longer a sufficient bulwark against the increasing threats. Instead, the entire process must be evaluated and monitored so that each individual piece of the network is understood fully. If a part of the system starts behaving in an abnormal way, then an understanding of what that specific PLC or component affects must be immediately known. The most effective protective programs will be able to function without needing any downtime, and will also be able to learn the network easily. Whenever the defense program gets triggered, it needs to not only provide a general alert to the process operator, but must also be able to provide context so that the previous knowledge of how the system works can be applied to mitigate the current problem.

Currently, the oil and gas industry has transitioned to what is being termed a ‘holistic’ approach to cyber defense. In order for the best security possible to be employed, the human element of process control must function in tandem with the autonomous programs. The human component of process operation, where it exists, can be unpredictable and present vulnerabilities that may not be known or anticipated. Everything must be considered.

Industrial process operation involves many areas of risk, with cyber attack being just one. The right kind of planning and response to risk can mitigate the potential impact. Security efforts, technology, and knowledge must keep pace with threats which emerge to process pipeline security. Mountain States Engineering and Controls participates in the oil and gas industry throughout the western U.S.

Thursday, November 16, 2017

Forced Draft Cooling Tower With 20 Year Warranty

corrosion resistant HDPE cooling tower rated 50 tons with forced draft
Forced draft corrosion resistant cooling tower
with forced draft, rated 50 tons. Pioneer series.
Image courtesy Delta Cooling Towers
Delta Cooling Towers specializes in the design and construction of corrosion resistant cooling towers and similar equipment. Much of the tower construction is HDPE or other non-metallic material, enabling the company to offer a 20 year warranty on their equipment.

Cooling towers are employed worldwide in HVAC applications and process fluid cooling. In addition to their industry leading corrosion resistance, Delta Cooling Towers also offers anti-microbial protection which combats the growth of microbes responsible for Legionnaires Disease and other respiratory ailments. The various product lines cover heat transfer capacities to accommodate any installation.

There is a lexicon employed in the description of cooling tower performance and operation. Some commonly used terms, along with their meaning, is provided below. The terms and their meanings is pulled from the owner's manual provided by Delta Cooling Towers for their Pioneer series of forced draft cooling towers.

Share your process and HVAC cooling challenges with application experts, leveraging your own knowledge and experience with their product application expertise to develop an effective solution.

Cooling Tower Terms and Definitions

  • BTU - A BTU is the heat energy required to raise the temperature of one pound of water one degree Fahrenheit in the range from 32° F. to 212° F.
  • Cooling Range - The difference in temperature between the hot water entering the tower and the cold water leaving the tower is the cooling range.
  • Approach - The difference between the temperature of the cold water leaving the tower and the wet-bulb temperature of the air is known as the approach. The approach fixes the operating temperature of the tower and is a most important parameter in determining both tower size and cost.
  • Drift - The water entrained in the air flow and discharged to the atmosphere. Drift loss does not include water lost by evaporation. Proper tower design and operation can minimize drift loss.
  • Heat Load - The amount of heat to be removed from the circulating water through the tower. Heat load is equal to water circulation rate (gpm) times the cooling range times 500 and is expressed in BTU/hr. Heat load is also an important parameter in determining tower size and cost.
  • Ton - An evaporative cooling ton is 15,000 BTU's per hour.
  • Wet-Bulb Temperature - The lowest temperature that water theoretically can reach by evaporation. Wet-Bulb Temperature is an extremely important parameter in tower selection and design and should be measured by a psychrometer.
  • Pumping Head - The pressure required to pump the water from the tower basin, through the entire system and return to the top of the tower.
  • Make-Up - The amount of water required to replace normal losses caused by bleedoff, drift, and evaporation.
  • Bleed Off (Blowdown) - The circulating water in the tower which is discharged to waste to help keep the dissolved solids concentrating in the water below a maximum allowable limit. As a result of evaporation, dissolved solids concentration will continually increase unless reduced by bleed off.

Friday, November 10, 2017

Hydrostatic Pressure Liquid Level Measurement

differential pressure tank level indicator
Tank mounted differential pressure transmitter
measures hydrostatic pressure to derive liquid level
Image courtesy King-Gage
Liquid level can be inferred by accurately measuring the pressure produced by the height of a fluid column and knowing the density of the liquid measured. The measurement is comparative in nature, referencing some external pressure as a zero point. The zero point can be the surrounding atmospheric pressure, tank pressure, or the pressure exerted by another column of liquid contained elsewhere.

There are uncountable application scenarios, each with its own set of special conditions. Proper instrument selection, installation and calibration are essential to generating reliable and accurate results.

The King-Gage TeleSensor™ liquid level transmitters are specially designed to provide level measurements across a wide range of liquids using a force balance principle in a pneumatic sensor. Sensor output can be either a pneumatic signal or 4-20 mA. The pneumatic force balance arrangement provides immunity to long term drift, hysteresis and temperature changes. A diaphragm isolates the sensor from the process liquid. Mounting is compatible with 2", 3", or 4" class 150 ANSI flanges. Various options for diaphragm and flange materials are available to accommodate a range of process media.

More detail is provided in the document included below, along with application examples. Contact product specialists to share your application challenges and get effective solutions.

Thursday, November 2, 2017

Steam Condensate Return Stations

duplex condensate return station
Duplex condensate return station
Image courtesy Roth Pump
Closed steam systems produce condensate, a dense source of heat. By design, the delivery of heat in a steam system is almost entirely accomplished using the heat of vaporization, with any sensible heat transfer probably being more coincidental than intentional. Condensate will contain most of the sensible heat that was added to the feedwater to get it to the boiling temperature. Conserving that sensible heat through a reuse of the hot condensate is a huge energy saving step. The condensate must be collected and returned to the boiler in a effective manner.

A condensate return station is a common means of moving condensate back to the boiler. It will generally consist of a collection vessel for the liquid condensate and one or more pumps to provide the motive force to move the liquid along its return path. Reliability is a key factor for these systems, since it is conceivable that they may need to perform on a continuous basis for years. A duplex pump arrangement can provide some backup, as well as extra capacity for accommodating large inlet flow. This is an installation where investing in rugged hardware can pay dividends in reduced maintenance burden and trouble free performance for the long term.

Roth Pump Company has been designing and manufacturing condensate return stations and other steam system related components for many years. Their experience and expertise are part of each and every system that leaves their factory. By incorporating low RPM motors, heavy duty pumps, and other features into a compact form factor, the company is able to offer a number of systems that meet a wide range of applications and deliver solid long term performance.

Share your steam system and condensate return requirements and challenges with application experts, leveraging your own experience and knowledge with their product application expertise.


Thursday, October 26, 2017

When to Use a Globe Valve for Fluid Process Control

cast iron globe valves
Cast iron globe valves are utilized extensively in steam,
HVAC, and other commercial and industrial applications
Image courtesy of Crane Co.
Industrial process control often involves the regulation of fluid flow. There are almost uncountable types and variants of flow control valves, each with a particular set of attributes that can make it the advantageous choice an application.

When the process calls for controlling flow over a range of possible values, known as throttling, a globe valve may be a good candidate for the application.

Globe valves are characterized by the change in direction of fluid flow as it passes through the valve and around the plug positioned in an opening through which fluid must pass. The plug is connected to a stem extending to the exterior of the valve body through the bonnet. Movement of the stem will reposition the plug in relation to the opening, providing a successively larger or smaller opening area through which fluid can pass.

Globe valves are available in tee, angle, and wye configurations, as well as an enormous range of special configurations to suit specific applications.
simplified globe valve diagram
Simplified globe valve diagram
Image courtesy Wikipedia


What are some potential advantages of globe valves?
  • Good throttling and shutoff capability
  • Comparatively easy maintenance
  • Comparatively short travel of plug from open to closed position
  • Seats can usually be resurfaced when worn
What are some limiting factors for globe valves?
  • Higher valve pressure drop than some other designs
  • No straight through fluid path
  • Potentially higher actuator torque requirements than other valve types
  • Seal area is unprotected from exposure to process fluid flow
When flow throttling capability is the overriding concern for an application, a globe valve is a good candidate for consideration. Share your flow control challenges with valve and automation specialists. Combining your process knowledge and experience with their product application expertise will produce effective solutions.

Friday, October 20, 2017

Wet Bulb Temperature and Cooling Tower Performance

corrosion resistant cooling tower induced draft type
Corrosion resistant evaporative cooling tower
Image courtesy Delta Cooling Towers, Inc.
Evaporative cooling towers enable many buildings across the globe to enjoy moderate interior temperatures. They serve as the final heat transfer step that moves heat from the building interior to the surrounding environment. In addition to their extensive application throughout large residential, commercial and industrial HVAC systems, their are numerous process cooling applications that employ evaporative cooling towers as an effective means of heat rejection.

Delta Cooling Towers, Inc. is a globally recognized manufacturer of corrosion resistant cooling towers, air strippers and tanks fabricated of HDPE to provide extended life service. The company posted an article entitled "Understanding Wet Bulb Temperatures And How It Affects Cooling Tower Performance". The original post is on this page of the company website, and all credit for the article goes to them. We share it below also, slightly edited for format on this forum.  From the article...

A cooling tower primarily uses latent heat of vaporization (evaporation) to cool process water. Minor additional cooling is provided by the air because of its temperature increase. Cooling tower selection and performance is based on water flow rate, water inlet temperature, water outlet temperature and ambient wet bulb temperature. Ambient wet bulb temperature and its affect on performance is the subject of this article. Ambient wet bulb temperature is a condition measured by a device called a psychrometer. A psychrometer places a thin film of water on the bulb of thermometer that is twirled in the air. After about a minute, the thermometer will show a reduced temperature. The low point when no additional twirling reduces the temperature is called the wet bulb temperature. The measured wet bulb temperature is a function of relative humidity and ambient air temperature. Wet bulb temperature essentially measures how much water vapor the atmosphere can hold at current weather conditions. A lower wet bulb temperature means the air is drier and can hold more water vapor than it can at a higher wet bulb temperature. For example:
Since cooling tower cells cool water by evaporation, the wet bulb temperature is the critical design variable. An evaporative cooling tower can generally provide cooling water 5° - 7° higher above the current ambient wet bulb condition. That means that if the wet bulb temperature is 78°F, then the cooling tower will most likely provide cooling water between 83° - 85°F, no lower. The same tower cell, on a day when the wet bulb temperature is 68°F, is likely to provide 74° - 76°F cooling water. When selecting a cooling tower cell, the highest or the design wet bulb temperature your geographical area will encounter must be used. Highest wet bulb temperatures occur during the summer, when air temperatures and humidity is highest. For example, in Indianapolis, Indiana, the design wet bulb temperature is 78°F. Historically Indianapolis can expect less than one hour per year that the conditions exceed a 78°F wet bulb. Typically, 6,000 hours a year will have a wet bulb of 60°F or lower meaning that a cooling tower cell designed for a 78°F wet bulb will be able to make 65-67°F water for 6,000 hours per year nearly 70% of the year. Most cooling towers are capacity rated at a "standard" wet bulb temperature of 78°F. That means on the days when the wet bulb temperature is 78°F, the tower will produce its stated capacity. In other words, a tower rated to produce 135 tons of cooling will produce 135 tons of cooling at a 78°F wet bulb temperature. At a higher wet bulb temperature, the tower cell capacity to produce colder water decreases. Every location has a unique design (worst case) wet bulb temperature that is published by organizations such as ASHRAE and can be obtained easily.

What does it mean when your cooling tower water temperature is higher than the normal 5-7°F above the current wet bulb temperature?

  1. Your cooling load may be larger than the rated capacity of your cooling tower.
  2. Your cooling tower may have lost efficiency
  • Due to scale build up on the tower heat exchange surfaces.
  • Due to loss of air flow across the heat exchange surfaces.
  • Due to improper water flow from clogged nozzles or pump performance
What can you do to improve your tower performance? 

  • Add tower cell capacity
  • Check for the efficiency losses described above
  • Replace the heat exchange surfaces with new clean fill
  • Check for proper airflow
  • Check the water flow is at design
  • Check that nozzles are not clogged or broken


Cooling tower performance is tied to ambient wet bulb conditions. Higher wet bulb temperatures occur in the summer when higher ambient and relative humidity occurs. Initial system design and proper system maintenance is critical to be certain your cooling tower is providing desired cooling.

For more information, or to discuss your own heat transfer challenges, contact a product application specialist. Combine your own knowledge and experience with their application expertise to develop an effective solution.

Wednesday, October 4, 2017

Refinery Explosion Analysis and Animated Video Reenactment



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. The video illustrates their animated reenactment and causal analysis of an explosion that occurred at a refinery in Louisiana in 2016. Check out the video and sharpen your senses to evaluate potential trouble spots in your own operation. Share any questions or concerns with process control specialists and reduce the level of risk at your facility.

Thursday, September 28, 2017

Breathing Air Purifiers

breathable air purifier system
A breathing air purifier unit processes
compressed air, making it suitable for respirators.
Image courtesy SPX Pneumatic Products
There are many instances throughout science and industry where tasks must be performed by human operators in environments without breathable air. In many of those cases, it is necessary to provide a positively pressurized enclosed space around the operator's face to isolate the breathing passages from potentially harmful vapors, dust, or pathogens in the work area.

Applications in the petrochemical industry, as well as asbestos abatement, paint and coatings, tank cleaning and more have specific jurisdictional requirements for the provision of breathing apparatus for worker protection. A compressed air source is processed as it passes through a purifier which imposes a six stage filtration process on the compressed air inlet prior to supplying the breathable air to safety hoods or masks.

  • Removal of solid and liquid particles or droplets greater than 1.0 micron.
  • Oil and liquid aerosol removal down to 0.1 micron.
  • Water vapor removal
  • Reduction of carbon monoxide level
  • Second particulate filtration stage to 1.0 micron
  • Activated carbon removes trace odors, oil vapor, and other components
Analyzing and monitoring the outlet air quality from the purifier unit is a good practice, to assure that target levels of oxygen, carbon monoxide, moisture, and carbon dioxide are maintained. OSHA and other jurisdictional bodies specify allowable levels for certain potentially harmful gases. The quality of the inlet air should be carefully assessed and protected during operation, since it is a primary determinant of the outlet air quality.

Share your process requirements with a pneumatic system specialist, combining your own knowledge and experience with their product application expertise to develop an effective solution.

Wednesday, September 20, 2017

Trunnion vs. Floating Ball Valves

trunnion mount ball valve for industrial pipeline use
Trunnion mount ball valves have upper and lower support
points for the ball.
Image courtesy International Standard Valve, Inc.
The design, construction, and function of a ball valve is generally well understood in the industrial fluid processing arena. Ball valves provide reliable quarter turn operation, compact form factor, and tight shutoff capability, making the ball valve a preferred choice for many applications. Some ball valves also provide shutoff of fluid flow in either direction. A primary valve trim design feature permits grouping of the many variants of industrial ball valves into two categories, distinguished solely by the way in which the ball is mounted in the body.

Floating ball valves use the seats and body to hold the ball in place within the fluid flow path, with the force of directional flow pushing the ball against the downstream seats to produce a tight shutoff seal. Many floating ball valves are capable of flow shutoff in either direction. The ball is rotated by a shaft connected at the top which extends through the pressure enclosure of the valve for connection to a handle or automated actuator. The floating nature of the ball limits the applicability of this design to smaller valve sizes and lower pressures. A some point, the fluid pressure exerted on the ball surface can exceed the ability of the seats to hold the ball effectively in place.

Trunnion mount ball valves employ the stem shaft and, you guessed it, a trunnion to rigidly position the ball within the body. The shaft and trunnion, connected to the top and bottom of the ball, establish a vertical axis of rotation for the ball and prevent it from shifting in response to flow pressure. The trunnion is a pin that protrudes from the bottom side of the ball. It sits within a bearing shape, generally cylindrical, in the base of the body.

Because of their structural design, trunnion mount ball valves are suitable for all pressure ranges and sizes.They are used by many manufacturers as a basis of design for their severe service ball valve offerings. A trunnion mount ball valve can also be advantageous for applications employing valve automation. Since the ball is not held in place by a tight fitting seal arrangement, operating torque tends to be lower for comparably sized trunnion mount valves, when compared to floating ball valves.

On page 3 of the brochure included below, the exploded view of a trunnion ball valve shows the location of the trunnion assembly.

Whatever your valve application challenge, share it with an industrial valve expert. Leverage your own process knowledge and experience with their product application expertise to develop an effective solution.