In 2- to 30-inch bore sizes, 150 to 1500 Class, models employ patented redundant sealing technology: a primary seal and a secondary seal on each side of the trunnion supported ball. There is no pressure drop through the full opening valve plus lower automation costs are lower since it is a quarter-turn valve. These ball valves are for refined products pipelines, pig launchers/receivers, manifolds, or storage and injection wells.

Quarter-Turn Plug Valves
Weco ULT and DR plug valves are premium, quarter-turn valves designed for a wide range of standard and sour gas drilling, production and well-servicing applications. These rugged valves are offered in single- and dual-body designs in pressures to 20,000 psi. They range in size from 1 to 4 inches and come with threaded, Weco wing union, flanged ends, or combinations thereof.

When the valve is closed, the dual segment seal provides the sealing reliability of redundant sealing members on the downstream side of the valve. In 3-inch and larger sizes, the ULT plug valve also employs a two-piece plug and stem design.

Valve and Actuator Package
The TRIAC F91 valve/actuator package from A-T Controls is suitable for oil field, refinery, chemical processing, and other corrosive and caustic environments. The F91 stainless-steel flanged ball valves feature rugged construction, solid unibody and patented pyramidal stem packing, while regularport design minimizes cost and reduces operating torque. To save installation time and work, the valves feature a patented directmount actuator pad and can be ordered pre-assembled with robust, weatherproof WE electric actuator. The ANSIclass 150 valves are available in sizes from 0.5 to 6.0 inches.

Explosion-Proof Solenoid Valve
The new high-flow high-speed EExd Namur Series solenoid valves from Alcon are designed for use in hazardous area/extreme environment applications. Offering universal 5/2 or 3/2 operations in offshore, processing and chemical industries, the series is suitable for piloting single or double actuators on Namur solenoid valves.

An explosion-proof, submersible, watertight and dust-tight aluminium body for indoor or outdoor use, along with Nitrile seals, ensures reliable operation while meeting requirements for a wide range of environments.

These valves are designed for use with actuators controlling butterfly and ball valve systems in hazardous areas found in offshore, paper, recycling, food processing and chemical industries.

Seat Control Valve
Flowserve Corp. announces the Worcester CPT characterized seat control valve. The CPT series ball valve is engineered as a control valve and provides reliable operation and precise valve positioning in the most critical throttling conditions. These valves offer many customizable features that enable them to be used for some of the processing industries’ highestprecision applications.

The valves can be used in systems that control steam pressure or pH levels, operate in low-temperature cryogenic conditions or up to 1000° F (538° C), and meet EPA and OSHA specifications for containing toxic chemicals. Widely used in the oil and gas industry, the CPT has been approved by Factory Mutual for fuel gas safety shutoff service and flow control.

Metal-Seated Ball Valve
Marvin Valve’s MS3000 Series is a heavy-duty, metal-seated ball valve engineered for high pressure and temperature applications with an extended bonnet standard for pipe insulation and enhanced packing. The
MS3000 Series Standard or Full Port Ball Valve is a hard (metal or carbon-seated) valve designed for ease of maintenance with double body seals and enhanced stem packing.

The metal seats are identical upstream and downstream and can be interchanged during routine maintenance, thereby extending the effective life. Designed for applications with pressures to 990 psi (69 bar) and temperatures to 1000° F (538° C), this ball valve is ideal for condensate, steam or gas service.

Valve Controllers
Topworx has recently added a new member to its DXP range of valve controllers. This unit is ideal for the oil and gas industry and other applications that require precise position feedback. The Valvetop DXP with 4-20 mA analog feedback offers an innovative design that is unique to the industry.

The single pushbutton autocalibration feature eliminates zero/span interaction and reduces set-up time by 95%. Reverse directions are automatically accounted for during the calibration process, because it can be calibrated in both actuator/valve rotational directions without adjusting the feedback device position. Simply apply power to the unit, and press the autocalibration button.

Safety Chainwheel
The Babbitt Safety Hammer-Blow Chainwheel allows plant personnel to operate out-of-reach high-pressure valves easily from the floor by the simple pull of a chain without having to climb ladders. This product’s configuration provides a secondary attachment device that prevents the possible danger of a falling hand wheel to which a Babbitt Safety Hammer-Blow unit is attached. With this device, the chainwheel and handwheel are suspended at a safe overhead distance until replacement or reattachment.

These ductile-iron safety chainwheels fit hand-wheel rim diameters from 6 to 36 inches and are engineered to deliver long-term reliability in refining, processing and petrochemical applications. Galvanized, rust-proof, stainless-steel, spark-resistant, brass lock-link chain and Master Links are available.

Series 3000 XPIS Gas Detector
Honeywell Analytics introduces the Series 3000 XPIS gas detector for industrial applications. This robust gas detector utilizes existing two-wire systems to monitor for toxic and oxygen gas hazards in potentially flammable environments.

The device’s intrinsic safety (IS) and explosion-proof hazardous area approval allows the detectors to be wired alongside other field wiring without IS certification. This removes the need for cable segregation as required by IS-certified detectors, making the device both cost-effective and versatile. Operating on a standard 2-wire 4-20mA loop that makes it suitable for new and retrofit applications, the Series 3000 serves a variety of demanding industrial environments: exploration and drilling platforms, production platforms, onshore oil and gas terminals, refineries and chemical plants, power plants, wastewater facilities, utilities and others.

Alarm Analysis Tool
Emerson Process Management has introduced an Alarm Analysis tool designed for its Ovation expert control system. The system is a component of the company’s PlantWeb digital architecture, which delivers process and equipment diagnostics data over digital buses to improve plant operations and streamline maintenance activities. The Alarm Analysis package examines alarm data collected by the Ovation historian,
providing the user with information necessary to minimize unnecessary alarms. This, in turn, enables plant operators to more effectively address real, high-priority issues and focus on actionable items.

This tool offers various statistical analysis functions, including operator response analysis and plant upset analysis, as well as auto-correlation analysis, which considers the causal relationship between alarms, providing additional valuable insight for optimizing the generation and reporting of alarms.

Curved Bill Check Valve
The Curved Bill Tideflex Check Valve from Red Valve Co. is designed to enhance sealing, especially in lowlying areas with little backpressure. The valve is constructed entirely of rubber, making it virtually immune to rust, corrosion and weathering. The curved bill offers increased flexibility to better seal around entrapped debris, and the headloss of the valve remains exceptionally low. Applications include highway runoff, flood control CSO/SSO systems, site drainage, stormwater discharge, sewer systems, coastal discharges, odor control or any application requiring backflow prevention. The valve is available in sizes to 96 inches.

Diaphragm Valve and Control System
The coupling of Burkert’s Type 2031 Diaphragm Valve (1/2- to 4-inch process connections) and Type 8630 TOP Control System provides chemical equipment professionals a variety of intelligent on/off, positioning and proportional control options.

The Type 2031 is designed to accommodate polluted, dirty, abrasive and high-viscosity fluids. Featuring a two-way 316L stainlesssteel body—permitting higher flow rates than those achieved via conventional diaphragm valves—this maintenance-free valve is a suitable alternative to ball valves. The self-draining Type 2031 is corrosion-resistant and built for long service life.

The Type 8630 TOP Control System—the actuator-mounted PID controller or positioner for the company’s line of diaphragm and globe-style valves—features the Process Tune function for optimal control of the 2031 valve. This system, a self-calibrating digital positioning unit, provides on/off and continuous functionality, and also offers self-PID tuning. This allows optimized PID values to be automatically set to control a process, and the set point modulator prevents the loop from becoming unstable and causing system damage.

Electronic Product Configurator
ASCO has released its new electronic Redundant Control System (RCS) series product configurator. From the convenience of a computer, users can build a catalog number of an RCS Rev. C unit. They will also be able to download top level drawings, wiring drawings, SIL information, an O&M guide, and the RCS catalog.

The product configurator is available through the ASCO public site at www.ascovalve.com/RCSConfigurator. The configurator will not only allow the user to build a valid construction, it will also disallow all invalid combinations of features.

Valves for Transformer Oil Applications
Unifin offers a line of heavy-duty transformer oil valves, manufactured under the company’s Cardinal brand. Cardinal valves are specifically designed to meet the demanding requirements of transformer oil applications. To perform reliably under extreme operating conditions, these valves are rated for temperatures ranging from –40º F (–40º C) to 212º F (100º C). All parts are made from non-corrosive or a suitably protected material to withstand outdoor exposure on external surfaces and hot transformer oil on internal surfaces.

These valves are robust in design, so that over-tightening or minor abuse encountered in handling or during factory/field installation will not result in valve malfunction.

Fluoropolymer Diaphragm Valve
A new fluoropolymer diaphragm valve from the Partek operation of Parker Hannifin—the 20 Series—features a flow path and valve seat area that optimizes fluid flow dynamics, for minimal pressure drop and enhanced flow rates, and resistance to aggressive media. As a result, this valve offers a life of more than a million cycles in slurry applications, a greater than 50% improvement over Partek’s standard DI water/chemical valve technology.

Compliant with the SEMI-F57-0301 standard for polymer components, the new valve has a body machined from ultra-high purity PTFE for superior chemical resistance, and a one-piece, precision-machined diaphragm. It is available in three orifice sizes of 1⁄4, 1⁄2 and 1 inch, with port sizes ranging from 1⁄4 to 11⁄4 inches.

FOCUS: COMMERCIAL CONSTRUCTION

Zone Valves
Dwyer’s Series ZV2 and 3ZV2 Zone Valves are made for use with temperature controllers and thermostats to control temperature in HVAC systems. The valves control the flow of hot and cold water in the HVAC system thereby controlling temperature. Units come in two-way and three-way constructions and incorporate a bi-directional motor. They feature an easy push-button removable actuator design for ease of installation.

Supplied in ½, ¾, 1 and 1¼-inch sizes, valves are for use with supply voltages of 120, 24 or 230 Vac. Inputs are floating or modulating with 4-20 mA or 0-10 Vdc.

Differential Bypass Valve
A new Differential Bypass (DB) Valve designed to control excess flow in hydronic systems has been introduced by ITT Bell & Gossett. When there is a reduction in demand, the valve acts as a bypass while ensuring adequate flow to the remaining open circuits. Designed to be used in systems where heating loads may be excluded from the circuit as zone valves close, the differential bypass valve also helps reduce velocity noise caused by excess flow through the circuits while maintaining the pump head at a constant valve.

Developed for hydronic systems utilizing zone valves, the new valve offers the following features: a ¾-inch connection, all-brass body with non-ferrous internals; and a horizontal or vertical installation. Its maximum working pressure is 150 psig and can operate at up to 230° F (110° C).

Rigid Coupling
Victaulic has introduced the Style W89 AGS Rigid Coupling for use exclusively with stainless-steel pipe
Schedule S10 or higher. Developed for use with HVAC and industrial pipe installation to provide an inflexible joint, the coupling greatly reduces linear and angular movement through the use of wedge-shaped coupling housing keys that fully engage the grooves to provide rigidity on valve connections and other points where inflexibility is necessary.

Available in sizes from 14 to 24 inches (350 to 600 mm), these couplings are provided with plated bolts and nuts and FlushSeal gasket Grade “E” EPDM for multiple uses. Grade “T” nitrile and Grade “L” silicone are also available. Offered in standard galvanized steel or painted upon request, the couplings are suitable for use on stainless-steel piping where the corrosion-resistant properties of stainless steel are not required for the external environment.

Pressure Transducer
Setra Systems, Inc. announces the Model 209 pressure transducer. Rated for a variety of cost-sensitive applications, this transducer is made for use in HVAC applications, as well as for fuel cell development, OEM and industrial applications. It is compatible with a number of liquids and gases and contains no seals or “O” rings that could cause leakage. The weather-resistant transducer offers a small footprint (1.62-inch diameter x 2.24 inches, end to end) and is lightweight (3.5 oz). It has a stainless steel/Valox housing, stainless-steel wetted parts, choice of cable, or optional Hirschmann or Packard termination.

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If you fully understand the cause, effect and prevention of cavitation as related to the process and the hardware, feel free to move on to another article. However, if you are new to the industry or don’t have a strong understanding of cavitation, read on.

Definition
Cavitation in a pipe occurs only with liquids, since by definition cavitation is the result of a liquid temporarily being converted to a vapor state followed soon after by a return to the liquid state. But if we have a pipe with liquid flowing through it and the liquid is under pressure, how and when does the liquid change itself to a vapor and then back again to a liquid? And why is this a problem?

How and When
Figure 1 demonstrates the velocity and pressure within a pipeline when the flowing media, liquid in our example, flows through a restriction. Obviously, the same amount of liquid is flowing through all portions of the piping. The smaller flow area of the restriction requires that the media flows at a much higher rate when passing through the restriction. Likewise, the media flows at a faster than normal speed as it approaches and as it leaves the restriction.

A few hundred years ago, Daniel Bernoulli pointed out that, ignoring friction, the amount of energy within a flow stream is the same at all points in a pipe and is the total of the energy due to velocity + pressure + elevation. If we consider a horizontal pipeline, then for energy to remain the same at all points in the piping when velocity increases, the pressure portion of the energy equation must be less. Summation: When the velocity in a pipe increases, the pressure decreases, sometimes to very low levels.

Liquids
If we heat water above the boiling point, it will turn to steam, i.e., the vapor form of water. The temperature at which water boils decreases as the pressure on the water decreases. At sea level it requires a higher temperature to boil water than it does in the mountains. If a mountain is high enough, water would boil at room temperature, i.e., we can boil water at any temperature by lowering the pressure to below the vapor pressure of the liquid at that temperature.

In a pipe, if the flowing velocity is great enough, the pressure within the liquid may fall to below the vapor pressure of the liquid. If this occurs, the liquid will boil at this location and turn to vapor.

Restrictions and Cavitation
Figure 2 portrays the velocity and pressure values as a liquid flows through a restriction. Note that at the smaller sectional area, the velocity increases and the pressure decreases. In the first graph, the pressure does not decrease to below the liquid’s vapor pressure; therefore it remains as a liquid at all points in the flow stream. There is a lower downstream pressure caused by energy losses caused by the restriction.

This is pressure drop. The lower graph shows what would occur if the velocity were to be great enough to cause the liquid pressure to fall below its vapor pressure value. At the point where this first occurs, some of the liquid converts to vapor and this conversion process will continue as long as the pressure remains below the vapor pressure of the liquid. However, some short distance downstream of the restriction, the flow area increases and the velocity returns to normal, raising the liquid’s pressure to above the vapor pressure. When this “pressure recovery” occurs, the media returns to a liquid state. The vapor is said to implode back to a liquid – i.e., cavitation.

Why Should We Care?
First, if cavitation occurs, the flow volumes no longer act in accordance with established flow sizing equations, thus rendering inaccurate the data upon which the valve and piping sizes were selected.

Second, cavitation is accompanied by considerable noise levels. Described accurately as sounding like heavy gravel passing through the pipe, cavitation can create noise levels above those acceptable for nearby personnel.

Third, cavitation is accompanied by often severe damage to the valve and downstream piping. The implosion from vapor to liquid removes surface particles from contacted materials, eventually destroying the subject component.

Therefore, we want not only to understand what cavitation is, but what we might do to prevent its occurrence.

If the Restriction is a Valve
Figure 3 portrays the effect on velocity and pressure that might be expected when a valve is controlling flow.

As a liquid flows through the valve, the flow area is less in the valve than in the open pipe and the flowing velocity in these areas is higher than in the open pipe. Additionally, the valve may cause a distortion of the flow stream such that lesser and greater flow volumes occur across the open areas.

Shown for example and discussion is a butterfly valve and a globe valve. Each acts as a variable restriction to the flowing media but each has differing affects on the flow stream and the likelihood of whether cavitation may occur.

Butterfly valves with their relatively straight through flow path, allow very high velocities to occur within and downstream of the valve. Globe valves have a rather torturous flow path, thus the internal flowing velocities are less than in a butterfly valve, given the same eventual pressure drop. Is one valve type more likely than another to create a situation where cavitation occurs? Globe type valves are often referred to as “high recovery” valves, whereas butterfly valves would be said to be “low recovery” valves. What does this mean, and how does it relate to the onset of cavitation?

Earlier in this article it was stated that the pressure “recovers” as the velocity slows downstream of a restriction. The same applies when a valve is employed as the restriction. Internal to the valve there is higher velocity than there is both upstream and downstream.

When the velocity increases internal to the valve, the pressure decreases. Downstream, the velocity slows and the pressure increases, or recovers, from the lower values internal to the valve.

With its more torturous flow path, a globe valve creates an equivalent pressure drop to that of a high butterfly valve but with lower velocities within the valve. Therefore, given the same pressure drop, the pressures internal to the globe valve will not be reduced to as low of a level as they would be in a butterfly valve. Since there is a smaller difference between the internal pressures of a globe valve and the downstream pressure, the globe valve is described as a low recovery valve. Logically, butterfly valves are described as high recovery valves.

Given identical differences between upstream and downstream pressures (pressure drop) there will be lower pressures internal to a butterfly valve than in a globe valve, although again, each causes the same pressure drop.

Figure 3 shows three situations. One is where the internal pressure of a high recovery and a low recovery valve is equal. The downstream pressure will be greater, by definition, for a high recovery valve.

The second situation shown in Figure 3 shows that while the downstream pressure, and pressure drop, may be identical with either a high or low recovery valve, the internal pressure within the high recovery valve will fall to a lower value that it does within the low recovery valve, and may fall below that of the vapor pressure of the liquid. Thus one valve type might experience cavitation while another, though controlling the same pressure drop, may not experience cavitation.

The third situation shows that a high recovery valve may induce cavitation even though the pressure drop it creates is less than the pressure drop caused by a low recovery valve.

If using a valve to cause a pressure drop (as opposed to control of flow volumes), it is safe to say that a low recovery valve will resist causing cavitation more so than a high recovery type. Of course, all valves can cause cavitation and to a differing degree at different travel positions. To predict if a valve will experience cavitation, certain valve manufacturers have performed extensive testing and can be relied upon to provide prediction and prevention information to users.

Can We Design to Reduce Cavitation?
Absolutely. With the information available from your valve supplier, it is possible to select an optimum valve type. Occasionally, it may be possible in a pressure control application to fit two or more high recovery valves in tandem within the piping, taking an equal fraction of the drop across each valve. In addition, some valve manufacturers have developed extremely effective “trim” or valve internals that combat both the onset and effect of cavitation. Again, look to your supplier for assistance.

ED HOLTGRAVER is CEO of QTRCO, Inc. (www.qtrco.com), located in Tomball, TX. Reach him at 281-516-0277.

The Pressure Relief Valve
The pressure relief valve is designed to provide protection from over-pressure in steam, gas, air and liquid lines. The valve “lets off steam” when safe pressures are exceeded, then closed again when pressure drops to a preset level.

BY PATRICK A. TOENSMEIER

Few jobs are more critical to the development of a process engineer’s skills than specifying valves and actuators. Working as part of a team and dealing with a range of application needs, from performance requirements to code standards, installation schedules and aftermarket service, specifying provides young engineers with a wealth of on-the-job training and lays the foundation for building a store of problem-solving knowledge.

Yet this introduction to the hands-on world of process engineering is not without challenges, many of which reflect recent trends within the industry. For example:

The layoffs, corporate consolidations and business slowdowns of the 1990s that reduced staffing levels in the process industry, left young specifiers with less access to older colleagues who once mentored and shared their expertise with them.

Specifiers must increasingly acknowledge the bottom-line concerns of accounting departments and deal with pressure to procure products based on installation quotes rather than more expensive life-cycle cost projections.

There is a tendency among novice specifiers to bundle commodity and engineered valves together when seeking quotes, a practice that makes it difficult to get comprehensive information about products for severe-service applications.

Many young engineers are attracted to what one observer terms “the glitzy stuff”—distributive controls, computer systems and other high-tech components of an installation—rather than the actual hardware on which applications are based, leaving a significant gap in their understanding of flow-control technology.

Poor Specification Choices Are Costly
With business in the process industry on a solid upturn, the ability to produce experienced valve and actuator specifiers is critical to the growth and profitability of engineering companies and their customers. Poor specification choices may result in problems ranging from costly shutdowns of process lines to catastrophic plant failures. Among the sources engineers tap for guidance and expertise in specification are the suppliers of valves and actuators, both manufacturers and distributors, who report playing a more active role in this area.

“We are much more involved with the specification of valves than we used to be,” says Morris Lavergne Jr., Houston contractor sales manager for the Masoneilan business unit of Dresser Consolidated Industries. “When we first began doing this it was a value-added benefit. Nowadays, it’s a given.”

Lavergne attributes the growing involvement in specification by companies like Masoneilan, which supplies control valves, to a knowledge gap in engineering firms that stems from the downturn of the late 1990s, when experienced engineers left the industry and engineering graduates looked to other businesses for job opportunities.

When Lavergne entered the process industry 30 years ago, a project team of 10 had at least several engineers who knew a great deal about the products they were specifying. “Most specifiers now only have a handful of guys [company-wide] who know about control valves,” he remarks. “We have resident engineers who go on-site and work with our customers on our products, which they know inside and out. As a result, our customers don’t really need that level of expertise.”

“There’s a big age gap between the experienced engineers who are 50 and over and the younger engineers,” remarks George Milleret, president of Myers-Aubrey Co., a distributor in Tulsa, OK. “There are new hires, but few people in the age group between 30 and 50.” This loss of “tribal knowledge,” as Bruce Broxterman calls it, not only affects a company’s ability to specify valves for current applications, but has an impact on maintenance work at older installations. Broxterman, president of the Valve Group of Richards Industries, Cincinnati, OH, says that in these facilities, “There are quirks and unusual aspects of the plant that older engineers understood and knew how to handle. This information used to be passed along, but with all the changes in the industry, laying people off and transitioning ownership, it’s not always there anymore.”

One manufacturer in particular sees how the loss of institutional knowledge at many companies affects the abilities of young engineers. “The simple mating of flanges has suddenly become an issue,” says Ed Ross, marketing director for instrumentation products at Tyco Valves, Baytown, TX. “The experience of the engineer is not there when it comes to knowing how to put two flanges together correctly without having an issue with the gasket in between. You’d think it’s pretty simple, but we’ve had to sit down and write detailed instructions for that.”

Relationships Are Key
Manufacturers and distributors say that in many cases the best way for new specifiers to acquire practical knowledge for their jobs is to develop long-term relationships with them. This might appear self-serving, but vendors offer a wealth of technical information and application experience that specifiers can use to broaden their engineering knowledge and judgment. Manufacturers and distributors also say they want specifiers to make the right product choices, even if it means that in some cases they lose business to competitors.

“As a vendor we have a responsibility to educate [specifiers] and help them review their specifications to be sure they not only meet their process needs, but the codes and standards they have to comply with,” says Charlie Weiland, president and general manager of Chalmers & Kubeck-South, Watkinsville, GA. Weiland says his company has helped engineers specify lower-cost valves simply by learning the details of what an installation requires. “We say to the specifier,

‘Let’s talk about the job first and be sure we understand what you’re trying to accomplish, and that the valve you’re asking for is what you should have for that application from a metallurgy standpoint, a capacity standpoint, and a codes and standards standpoint.’ In some cases we might not get the order,” Weiland notes, “but at least we’ve done the right thing” in letting the engineer understand that the valve he or she was asking for was not the correct valve.

It’s essential that specifiers discuss projects with vendors as soon as possible, especially when they are building relationships with these companies. “It would probably be better to speak with a distributor first,” suggests Ross. If the distributor is experienced in the product a specifier needs, the distributor can provide direction, and “if the product required is unique or if the specifier needs additional information, the manufacturer can be involved.”

“Project specifications can be the easiest thing that you do or the hardest, depending on your reference material and whether or not you get any assistance from vendors, which is absolutely critical,” says John Faulkinberry, Houston contractor sales manager for Dresser Consolidated Industries.

A common problem that vendors note when discussing projects with new specifiers is a lack of detail about applications. Specifiers usually don’t present all the information a supplier needs to assist in the product selection process. To a large degree this is due to their inexperience, and is an important reason why face-toface meetings and relationships are vital to the learning curve.

“The biggest thing we have trouble with is getting complete application details,” says Broxterman. “That entails a variety of information: the media that flows through the valves, inlet-outlet pressure, flow rate, and even where in a pipe a valve will be installed.” The more specifiers can tell valve makers about what they want the valve to do, “the better we can do our job,” he adds.

Ross similarly advises that a specifier should research the requirements of an application prior to meeting with a supplier. The specifier needs to look at what the process conditions are, what materials are most suitable for that process, and what codes and standards will apply to the specification. Once this information is gathered, the specifier can determine what needs to be accomplished with the valve, and what type of valve he or she needs to buy, says Ross.

Milleret recommends that in addition to technical data, young specifiers must know how to accurately express themselves in language suppliers understand. The specifier “can’t have a conversation without knowing industry terminology,” Milleret says. This not only involves accurately describing the valves a specifier is thinking of procuring, but being conversant with their performance characteristics, metallurgy properties and relevant ASME codes.

Commodity vs. Engineered
A related issue is the tendency of inexperienced specifiers to bundle different types of valves together in an effort to streamline the bidding and supply process. “The term ‘valves’ covers a very broad category,” says Weiland. “One of the things a specifer has to be cautious about is not to group engineered products with commodity valves.” The problem is that by putting different valves in one broad category, specifiers create barriers to information that would help them make smarter choices regarding performance, installation and cost.

“When they do that, specifiers really put a gap between themselves, the manufacturer and people with the product knowledge to protect against [a valve selection] not meeting a specification or a code and standard,” Weiland notes.

“The potential for a valve to be installed in the wrong application because an engineer with specialty knowledge has been removed from the specification process increases considerably.”

According to many vendors, part of this comes from efforts by financial people to reduce procurement costs, a worthy effort, to be sure, but one that can produce unintended consequences such as early replacement of a valve or the failure of a process line. The best way to deal with this attitude, says Faulkinberry, is to explain its potential ramifications to the specifier, who needs to understand that a buying decision has a lot of issues to it. “There are upfront costs and long-term ownership costs. The entire cost of the product they’re purchasing can’t be valued in the initial quotation stage.”

“The procurement guys are doing what they’re supposed to do—drive down costs,” says Weiland. “But they have to be careful not to group products under an umbrella where they don’t belong, like engineered valves with commodity valves.” The older engineers knew what worked, whereas the younger engineers may yield more readily to the influence of the procurement process, he suggests.

Faulkinberry adds that the total cost of a project should be one of the first points a manufacturer or distributor explains to a specifier, even if there is initial resistance to learning about higherpriced valves. “It is my job as a technical salesperson to justify the cost that my products warrant,” he remarks.

Shopping the Net? Buyer Beware
Cost considerations may make some specifiers look to new areas as potential sources of supply. One such source is the Internet, a purchasing option that draws mixed reactions from distributors and manufacturers, though most discount the impact of online valve purchases.

“When you get on the Internet you really don’t know the reputation of [the vendors] you are dealing with,” notes Weiland. “There are a lot of pitfalls out there, and the term ‘buyer beware’ is very true, even in our industry.”

“The Internet might be fine for buying commodity products,” says Broxterman, “but if you’re buying engineered products, it’s pretty tough. It can be done, but all that application knowledge won’t be there.”

“It would be very difficult to make an online purchase of a control valve,” asserts Lavergne. “We’ve had many customers attempt to do that without
any success.”

“I don’t think our industry is Webbased at all,” says Milleret. “We are a competitive industry and a specifier can get a better price, but probably not on the Web.”

Ross suggests, “There’s nothing wrong with buying on the Web, but engineers should do their research to make sure they’re buying an apples-toapples product.”

Another alternative supply source is foreign manufacturers with operations in North America. Manufacturers and distributors advise against going this route unless the company convincingly demonstrates it has locally available products, ample inventory, technical assistance and extensive field-support capabilities.

“You have to look at the total lifecycle of a valve,” says Weiland. “These products require periodic servicing and may entail multiple repairs. The availability of replacement parts, technology, customer support and a long-term relationship should be of prime concern to a young engineer.”

Make Time for Education
Vendors actively promote educational opportunities for specifiers beyond those related to specific applications. Programs are designed to increase the awareness of young engineers about different types of valves and actuators, how they are used in installations and what makes them fail. The goal, the companies say, is to familiarize specifiers with the nuts-andbolts details of valves, focusing for the most part on generic designs and capabilities, and minimizing overt sales pitches for particular products.

One popular format is the “lunch-andlearn” presentation, which almost every distributor and manufacturer sponsors throughout the year in various areas for any specifier who wants to attend.

Some companies balance this approach with more targeted audiences. Faulkinberry prefers to train a handful of select specifiers for several hours, making technical presentations that can be generic or product related based on the group.

Another option is to invite specifiers to a manufacturer’s factory where they not only receive technical presentations on valves and actuators, but see how they work in a lab under simulated operating conditions. Ross says a key feature of the factory seminars his company presents is demonstrating the results of incorrect piping, installation practices and valve specification.

“Showing them what actually happens when you do things badly sticks out in their minds.”

Despite all these efforts, most of the education process depends on specifiers’ willingness to make time to learn the details of their trade.

“The engineer can’t be afraid to invest time in face-to-face meetings,” says Broxterman. “Everyone is busy and tends to shy away from that dreaded sales call or lunch-and-learn, or whatever it happens to be that’s going to take time out of the day. But if specifiers see this as an investment in their knowledge or in vendor relationships, then it has a great deal of value for making them better engineers, and their companies better from an operations standpoint.”

Writer PATRICK A. TOENSMEIER, based in Hamden, CT, specializes in manufacturing and technology issues. His background includes covering the global plastics and tooling industry for 20 years and writing for a variety of industry and business publications.

American Pipe Fittings Association
Represents manufacturers of fittings and couplings for our industry
              703.538.1786       

American Society of Mechanical Engineers
Develops standards for valves, ASME standards
              212.591.7000       
www.asme.org

American Supply Association
Represents manufacturers, wholesalers and distributors of plumbing valves
              312.464.0090       
www.asa.net

Fluid Control Institute
Represents similar companies as VMA and develops standards
              216.241.7333       
www.taol.com/fci

Fluid Sealing Association
Manufacturers of mechanical packings, sealings and gaskets
              610.971.4850       
www.fluidsealing.com

Hydraulic Institute
Pump manufacturers
              973.267.9700       
www.pumps.org

Industrial Distribution Association
Represents distributors of industrial products including valves
              404.266.3991       
www.ida-assoc.org

Manufacturers Standardization Society
Develops valve standards, MSS standards
              703.281.6613       
www.mss-hq.com

National Fluid Power Association
Manufacturers of hydraulic and pneumatic valves
              414.778.3344       
www.nfpa.com

Plumbing Manufacturers Institute
Manufacturers of plumbing valves
              847.884.9764       
www.pmihome.org

Some valves may be located in extremely hostile or toxic environments, which preclude manual operation. Additionally, as a safety feature, certain types of power actuators may be required to operate quickly, shutting down a valve in case of emergency.