Use a Swagelok Regulator to Speed up Analytical Systems

Posted by Katie Reid on Fri, Nov 18, 2016 @ 12:11 PM


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The lower the pressure of a gas, the shorter the time delay to the analyzer

In an ideal world, you would be able to get a fluid sample instantly from the process line to the analyzer. The real world, alas, it is far from ideal. So it's important to learn a bit about time delays and how do minimize them.

First, realize that a delay may occur in any of the major parts of an analytical instrumentation system: the process line, the tap and probe, the field station, the transport line, the sample conditioning system, the stream switching system, and the analyzer itself. A small delay at each stage will add up.

One way to minimize the delay is with a pressure regulator. In gas systems with a controlled flow rate, the lower the pressure, the faster the gas moves, which means the shorter the time delay.

Start at the tap

Ideally you want to tap the process line as close to the analyzer as possible. But you also want to stay upstream of drums, tanks, dead legs, stagnant lines, or other sources of delay. Because of that, you may have to make do with a location that's less than ideal. If the tap is a long distance from the analyzer, a fast loop is a good means of quickly delivering fluid to the analyzer and returning the unused portion to the process.

Another typical source of time delay is the probe. The larger the probe's volume, the greater the delay. Minimize the delay by choosing a low-volume probe.

At the field station

For an analyzer that requires a liquid sample it is better not to use a regulator. High pressure will help prevent the formation of bubbles. But with a gas sample, a field station is one of the means of reducing pressure in the transport lines. Time delay decreases in direct proportion to absolute pressure. At half the pressure, you will get half the time delay. The sooner the pressure is dropped, the better, so put the field station as close to the tap as possible.

There are a few different ways to configure the regulator. With a drop in pressure, almost all gasses lose heat. If the gas is close to its dew point, the result from this cooling is condensation. In some cases, the loss of heat may be great enough to cause the regulator to freeze up. In those cases, a heated regulator may solve the problem. If you don't expect condensation, a standard regulator will probably do. Read more about Pressure Regualators and how to read a flow curve here

If a liquid must become a gas before it can be analyzed by a gas chromatograph or other analyzer, it's time for a vapourizing regulator.

Another means of attaining a faster response is to move the regulator closer to the analyzer with the aid of a second fast loop.

The details

There's a lot more to these tips than simply plugging in a component. Vapourizing regulators, in particular, require extra care because the volume of a sample can increase greatly as it changes from liquid to gas. Done incorrectly, the addition of a vapourizing regulator can actually increase the time delay to the analyzer.

Fortunately for you, Edmonton Valve & Fitting loves to discuss regulators, analyzer systems and all things dealing with fluid systems. Tell us about your analyzer system and let's get started finding the right configuration.

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Topics: Sample Systems, Regulators

Let's Talk About Tagging

Posted by Katie Reid on Thu, Sep 01, 2016 @ 11:09 AM

(But not the spray-paint kind.) A tag makes sure that vital information always stays with the component


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Pictured above is an example of a custom tag that has been done up for hose. Important information is included for a quick reference for tracking and repurchasing. Get in touch with us today for you tagging needs.


Imagine you are giving your systems a quick once-over, and your eye falls on a hose. Has it been in service long enough that you should think about replacing it? What's it made of? Who made it? If you wanted to order another one, what's the part number?

If someone was thoughtful enough to tag the hose, you'll have all that information right at your fingertips.

Why you should tag

A tag is a simple way to keep vital information about a component right there with the component. You never know when that information might be needed in the future, and you never know who is going to need it. With a tag, anyone who needs the information will have it right away.

With a good tag, it's easy to track your parts and reorder them. A tag can tell you the part number, the purchase order number, install date, maybe even specs such as its working pressure and temperature. We'll put Edmonton Valve & Fitting's name on the tag if you buy directly from us, or the name of an intermediary that sells the part. If you have an urgent need to replace a hose, we've been able to get one out the door in less than an hour when the customer has been able to give us the tag information.

A tag also can be useful if you are gathering parts in a holding area prior to assembly. The tag can include a separate number for each valve, flow meter or other part. That way it's easy to check them off a list as they are installed.

If an inspector comes through and sees the part's CRN number on a tag, they'll know it's good to go without having to check it.

How we tag it

Stainless steel tags are by far the most common. Think of a soldier's dog tags, and you'll have the basic idea. We use a laser engraver to burn the information on a small piece of stainless steel, punch a hole in the tag and attach it with a wire to the part.

Lamacoids are also a popular choice. It's basically a sheet of plastic with two layers in different colors, typically a dark color on top and white underneath. In this case, the laser engraver burn away the top layer, resulting in clear white letters and symbols (though we have multiple color combinations to choose from). If you can type it out, we can put it on a Lamacoid label, including descriptions of the part and lists of safety precautions. We’ve even photocopied a drawing and loaded it into our system as an image to be burned into the Lamacoid. The plastic has a sticky back for easy adhesion on flat surfaces, making this a popular choice for panels. We've done Lamacoid tags as small as one square inch and as large as a standard sheet of paper.

There are other types of tags that usually show up on hoses. We can use self-adhesive labels, matte tags that can be color-coded, and Perma Tags with up to five lines of information and protected by a silicone gel and sleeve. We also offer a lanyard tag.

What we tag

We tag hoses, panels, regulators, valves, cylinders, and assemblies such as steam lances — nearly anything you want to order. While we're sure there are a few objects that can't be tagged, we probably can find a solution from among our various options.

We can also help you keep track of information through the use of tags. For example, we keep a spreadsheet of all the hoses we build for a customer, and assign a serial number to each. The tag will have the number, so all you need to do is read it off to us and we can tell you exactly what you have.

Adding a tag doesn't affect the delivery time, and it doesn't add much to the cost. In fact, it saves you time and labour because you won't have to track down information.

Since you're already reading this, you don't even have to track down Edmonton Valve & Fitting either. Just tell us what kind of tag you want, and what information you want on it, and we'll do the rest - get in touch today!

Topics: Custom Solutions, Hoses, Regulators

An Inside Look at Swagelok's Pressure Reducing Regulators

Posted by Katie Reid on Thu, Jul 28, 2016 @ 14:07 PM

They do only one thing, but they can do it in several different ways


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To get all the technical information on Swagelok's Pressure Reducing Regulators, download a copy of the K Series Catalogue here.


The name says it all. A pressure reducing regulator reduces pressure. That's it. It doesn't regulate flow, it doesn't regulate back pressure, it doesn't regulate anything else. It just makes sure that the downstream pressure stays constant.

But how does it do that?

It starts with a poppet and a seat. That's where the pressure drop takes place. When the poppet moves away from the seat, it opens up a space. A large space means a small drop in pressure. A small space creates a large drop in pressure. The poppet will move up and down as conditions change to give you the outlet pressure you've asked for.

Each regulator is designed to work best within a certain range of conditions. Bump up against one end of the range, and the pressure will build up enough to close off the inlet. That’s called lockup. Go all the way to the other end of the range, and the regulator will be wide open, and is no longer regulating pressure. That’s called choke flow.

Feel the force

Regulator operation — that is, moving the poppet as conditions change — is all about balancing forces. There are four forces.

The first is the loading force. In analytical systems, most regulators are spring loaded. There's a coiled spring in the top of the regulator pushing down. That's the part we can control, increasing or relaxing the force of the spring to get the outlet pressure we want.

Second is the force of a much smaller inlet spring. It's down under the poppet pushing up. It holds the valve against the seat and closes it off if there's no flow.

Third is the outlet pressure force, and fourth is the inlet pressure force.

The regulator automatically tries to maintain balance. If the flow rate suddenly increases, you'd have a higher pressure drop if no other elements changed. So the regulator will balance that by moving the poppet away from the seat and creating more area.

Not all regulators are spring loaded. Some are dome loaded, meaning that there's pressurized gas in a dome on top of the regulator. There are even designs that use a combination of spring and dome loading. And there is a type called a ratio regulator, which works off a set ratio of the dome pressure.

Righting droop

Regulators can be subject to droop, which means the outlet pressure increases somewhat as flow increases. Spring-loaded regulators are more susceptible to droop than other types. That's because as the spring lengthens, the loading force gets weaker. Using a longer spring will minimize this effect.

Dome loaded regulators also can experience droop. The use of a pilot regulator can help, adjusting the pressure in the dome as needed. Even better performance can be obtained by sampling the pressure downstream, called external feedback, and sending it to the pilot regulator.

There's no hard and fast rule about how far downstream you can tap. In general, try to stay within 10 or 15 diameters of the main regulator.

There's a lot more to be said about regulators, more than we have room for in a blog post. We'll be glad to talk with you about them; tell us what you want your regulator to do, and the conditions in which it has to operate, and we can help you pick out the best one for your needs. If in the meantime you would like to get your hands on the technical information for Pressure Regulators, K Series - download the catalogue.

Topics: Regulators

Need High-flow Process Regulators? Ask for RHPS

Posted by Katie Reid on Wed, May 04, 2016 @ 14:05 PM

We sent our associates right to the source for training and a tour of the factory

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  Pressure Regulators RHPS Series, pictured above, are available in sizes up to 4 inches with a working pressure up to 10,500 psi. To learn more about this regulator product line download the RHPS Series catalogue here.

When Swagelok wanted to add a line of high-flow process regulators, nothing could top the ones made by a company called RHPS. So Swagelok bought the company.

Pressure Regulators RHPS Series have been engineered for applications in the chemical/petrochemical, oil and gas, power, biopharmaceutical, semiconductor, and alternative fuels industries. Made of 316L stainless steel, the RHPS Series is more structurally sound than the cast designs and carbon steel used by some competitors. The cartridge design allows you to change the seat without taking the whole regulator out of the line. The series includes pressure-reducing regulators, back-pressure regulators and specialty regulators for applications such as tank blanketing.

RHPS Series regulators come in several different models: spring-loaded, dome-loaded and pilot models, in standard sizes up to 4 inches, and with customized flange sizes over 4 inches. The working pressure of the RHPS Series line up to 10,500 psi, but it also can handle challenging applications that require high flow or volume and only inches of water column pressure control.

RHPS training trip

To ensure we had the RHPS Series expertise in Edmonton, we sent two of our associates to the Isle of Man a few months ago to tour the factory where the regulators are made. Custom Solutions Manager/Swagelok field engineer Stacey Phillips and Drayton Valley account manager David Flett spent five days getting a thorough education.

"We went through the whole product line of the RHPS, learning all the different models that they have, and how to size regulators," Flett says.

The factory, which is also where Swagelok has its aerospace division, has 235 associates. That makes it a major employer on an island with a population of only about 85,000. With a capable work force, and with airplanes and ships always coming and going, the island makes a good base from which the RHPS factory can serve the world.

"The thing that stuck with me the most is that they're very quick to respond to special requests, especially for the RHPS line," Flett says. "They want to really support engineered-to-order and configured-to-order requests."

There also was a little bit of free time to check out the sights on the island, which sits in the Irish Sea between England and Ireland. Motorcycle fans know the island as the site of the International Isle of Man Tourist Trophy Race, known more familiarly as the TT Race. Our associates got to tour part of the 37-mile course and talk to a past winner.

Now with CRNs

Most of the RHPS Series line already has CRN numbers, and we're working on the remainder. It's a large line, so if you want a particular RHPS regulator model that doesn't yet have its CRN number, don't worry. We will do our best to find one that will take care of your needs.

We can also troubleshoot regulators, eliminating or minimizing poor performance characteristics that can cause droop, choked flow, lock-up, hysteresis the Joule-Thomson effect.

Does it sound like we know a lot about RHPS regulators? We do. We'd like to share that knowledge with you. Download the Pressure Regulators RHPS Series catalogue, and then talk with us about the model that will work best for you.

Topics: Regulators

More Alphabet Soup: Swagelok Products & Industry Acronyms (P & R)

Posted by Katie Dennis on Fri, Nov 06, 2015 @ 16:11 PM

When you see these abbreviations, now you'll know what the letters mean


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When it comes to Swagelok and industry acronyms, we have you covered! From PrESS products to regulators, find out what they mean in our acronym series blogs. Have one that has you stumped? Ask Us here.


This is our third post detailing some of the acronyms you'll run into when you read our blog. Our first installment covered letters A through E. The second installment took us from F through N. This time around, we have room for only two letters: P and R. There's a lot to cover in that tiny slice of the alphabet.

PASS - A process analyzer sampling system is a device that automatically measures some aspect of the fluid in a system. A PASS typically consists of a sample tap, a sample system, an analyzer, a sample return, and a signal transmission and control system. Swagelok wrote the book on industrial sampling systems. From time to time we offer PASS training too.

PFA - Perfluoroalkoxy is a translucent, slightly flexible polymer developed by DuPont Co. It is most commonly used for lab equipment as it has an extreme resistance to chemicals. PFA flexible tubing is good for highly corrosive process applications. Swagelok offers a variety of fittings and tubing in PFA as well as ultrahigh purity PFA fittings. You can use Teflon or metal fittings with Swagelok PFA tubing. Swagelok also uses PFA for packing and seals in some of its ball valves. 

PrESS – Pre-Engineered Subsystems are a series of Swagelok components predesigned and pre-assembled for use anywhere that fluids are processed. They range from simple weldments to complex manifolds. The list includes fluid distribution headers, sample probe modules, calibration and switching modules, and others. We’re continuing to add to the list. This array of subsystems can be designed to customer specs, and are ready to plug and play.

PRV - A proportional relief valve is designed to open gradually as pressure increases. It opens when the system reaches a set pressure, and closes when the system falls below that same set pressure. They are available for liquid or gas service, but they should never be used as safety relief devices as specified by the ASME Boiler and Pressure Vessel Code.

PTFE - Polytetrafluoroethylene is a synthetic compound discovered by DuPont Co., and marketed by them under the Teflon brand name. One common application in fluid systems is TFE tape, used to seal pipe threads. Swagelok also makes PTFE hose. The X, S, and W series of PTFE hose are extremely flexible while maintaining strength. The secret is in a unique process that bonds a nonmetallic fiber braid to the outside of the hose's extruded smooth-bore PTFE core.

RHPS – No, it does not stand for "Rocky Horror Picture Show," at least not at Edmonton Valve & Fitting. This RHPS is a line of pressure regulators. The initials come from the Dutch company that developed for applications in the chemical/petrochemical, oil and gas, power, biopharmaceutical, semiconductor, and alternative fuels industries. The series includes pressure-reducing regulators, back-pressure regulators and specialty regulators for applications such as tank blanketing.

Stay tuned as we finish off the rest of the alphabet with our next post featuring acronyms from S to V!


Additional resources:


In a hurry or have a question? Please click here to get in touch - we respond fast! Or call 780.437.0640


 

Topics: Training, Valves, Sample Systems, Hoses, Regulators

Alphabet Soup Part II: Swagelok Acronyms From F to N

Posted by Katie Reid on Fri, Oct 16, 2015 @ 16:10 PM

There are some long and informative names behind all those letter combinations


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Product groupings that have common Swagelok acronyms include the Pre-Engineered Subsystem products, regulator series, and Swagelok fittings.


In an earlier post we went through some of the acronyms you'll run into when you read our blog. Last time we covered letters A through E. This time we continue on through the middle of the alphabet. Check back to see future posts that will take us all the way to Z.

FDH – Fluid distribution headers are common components used in a variety of gas and liquid applications. An FDH provides a flow path while allowing multiple outlets, acting much like a large branch fitting. This is one of the many preassembled subsystems available from Edmonton Valve & Fitting.

FLIR – Forward looking infrared radiometer cameras are sophisticated thermal-imaging tools for detecting leaks. Any time there's a problem that generates heat, a FLIR camera can find it. A hydrocarbon leak shows up as a cloud on the camera screen, even though it's invisible to the naked eye.

FLM – Fast loop modules are designed to handle high flows in sample transport lines to reduce time delays for online analyzer systems. Located at the analyzer shelter and offering a bypass, the Swagelok FLM can isolate the sample system and introduce a purge gas for system cleaning. The FLM extracts a sample through a filter while using the high flow rate of bypass to keep the filter element clean. 

FSM – When analyzing a gas sample, it's important to move the sample quickly. One way to speed up delivery is to lower the pressure. That's where a Swagelok field station module comes in. When this pre-engineered subassembly is placed directly off the supply tap, it lowers the pressure of a gas as soon as possible.

ISO – The International Organization for Standardization is an independent, non-governmental membership organization that sets standards of all kinds, from standard musical pitch (ISO 16) to sample preparation of iron ore (ISO 3082) to software testing (ISO 29119). Edmonton Valve & Fitting supports and maintains the ISO 9001 standard for quality management systems.

K Series – The letter K in our K Series regulators is a nod to the series origins at Kenmac Ltd., a British company that Swagelok acquired back in 2003. At the time, regulators were the only gap in Swagelok’s product line for analytical instrumentation. Since then, Swagelok has closed the gap to become your supplier for sample handling. The K Series includes 17 different models of pressure-reducing, backpressure and specialty regulators.

MPC – Our Modular Platform Component system lets you pack more instrumentation into less space. A substrate channel holds the drop-in components that provide the main flow path. Then it's literally a snap to add surface-mount components to create the fluid distribution system. Swagelok also makes an interactive software tool called the MPC Configurator to help you plan out the details.

MTR – When a customer purchases tubing, they are able to conveniently access our material test report website that will provide details on tubing heat numbers. For example, a sheet might tell you that a particular type of welded tubing contains so much chromium, nickel, and other elements. It also could list the tensile strength, hardness, and other properties. It also show that the product has passed a series of tests. 

NPT – The National Pipe Thread standard applies to tapered threads on pipes and fittings. NPT threads usually require application of sealing compound or tape to prevent leaks.

Up next we will be posting acronymns in the P-R range! 


Additional resources


In a hurry or have a question? Please click here to get in touch - we respond fast! Or call 780.437.0640.


 

Topics: Q&A, Resources, Fittings, Regulators

New Filter Retainer Assembly for Swagelok K Series Regulators

Posted by Katie Dennis on Thu, Oct 01, 2015 @ 09:10 AM

Improved one-piece assembly means fewer parts to handle and better results


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Looking for more information on this product line? Request a copy of the Pressure Regulators K Series catalogue.


Swagelok is always looking for ways to improve its products. Even a small tweak can make someone's life better in the field. A recent example is the new filter retainer and NPT ports for our K Series regulators.

These are improvements that distributors and customers had asked for, so Swagelok paid attention.

One-piece assembly

The new filter design is a one-piece assembly that replaces the separate "circlip" retaining ring, mesh and filter ring of the old design. The carrier maintains a seal around the inlet port wall, ensuring that contamination does not bypass the filter.

By adopting the new style of filter retainer, Swagelok has also been able to machine the regulator body's female NPT ports to Swagelok's NPT more stringent standards. (Previously, the ports were machined to commercial standards.) The result is a more consistent thread form, which can lower the chances of galling when components are installed.

Douglas Nordstrom, Swagelok Sr. Product Manager for Valves, has already been receiving positive feedback from customers on the recent change. Nordstrom says "they have also seen FAR fewer returns for galled threads and contaminated regulator seats, and selling fewer replacement kits (as a better filter will protect the seat longer)."

Maintenance tips

Removing the new style of filter retainer requires a pick or sharp tool that locks into the filter mesh or carrier. We have an appropriate tool (order number 9R0200), but any O-ring pick will do the job.

Don't reinstall a used filter. Removal usually damages the mesh to the point where it should not be used again.

Swagelok also offers filter insertion tools that press on the outside of the mesh, eliminating the chance of damage to the mesh or the retainer. Order 9R0198 for 1/8-inch and 1/4-inch ports, and 9R0199 for 3/8-inch and 1/2-inch ports.

Although the mesh is exactly the same in the old and new filters, the old-style filter retainers can't be used in the new NPT ports. The new-style filter retainers, however, can be installed in either the old or new K series regulator body.

We'd be glad to show you the new filter retainer and discuss all your fluid system needs. Just give us a call or stop by. 


Additional resources


In a hurry or have a question? Please click here to get in touch - we respond fast! Or call 780.437.0640


 

Topics: Regulators

As Edmonton Valve Prepares to Enjoy the Holidays…

Posted by Katie Dennis on Mon, Dec 22, 2014 @ 12:12 PM

Plan ahead to make sure you have all the parts you need

Edmonton Valve & Fitting will take a little time off for Christmas and to celebrate the arrival of 2015.

We'll be open for a half-day on December 24th and closed on December 25th and 26th. Similarly, we will work a half-day on New Year's Eve, and be closed on January 1st. This is also a time of year when Swagelok takes some days off, so please factor that into your plans when you order. Shipping will take a little longer around the holidays. Normal operations for Swagelok will resume on January 2nd.  

Of course, here in Edmonton we'll always make time for our customers if there's an emergency. If it is after-hours or on a day we are closed, call our office (780.437.0640) and follow the prompts. We will do our best to help you the best we can.

Feeling pressure?

The winter holidays can put people under a lot of pressure as they wrap up their work activities, buy presents and get everything ready to spend time with friends and family.  And talking of pressure, what better time for a quick review of pressure regulators?

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Swagelok offers a variety of pressure regulators, but how do you know which one is right for the job? Find out here.

Not long ago we presented two ways to find the right size regulator for the job. The quick way is to answer the following five questions:

1. What do you want the regulator to do? Usually it will be to reduce pressure, but sometimes you'll want a back-pressure regulator.

2. What is the inlet and outlet pressure ranges?

3. Will you be running a gas or a liquid through it?

4. What is the operating temperature?

5. What is the flow requirement?

With those answers, you'll narrow down your choices from the Swagelok catalogue. The second method involves some math, which you can download here.

Grading on the curve

Regulators are designed to perform at their best within certain ranges of pressure and flow. When you graph it out, you get a flow curve. Learn how to read these charts and you'll have a good way to see whether a particular regulator is right for your needs.

Expert viewpoint

We've brought Swagelok Field Engineer Eric Kayla to Edmonton to conduct in-house training on regulators. Here's part of a session he gave to our account managers and customer service representatives. It included these 7 facts about regulators.

Watch out for the creep

"Creep" is an industry term for when outlet pressure rises even though a regulator's poppet is closed. Every regulator is susceptible to it. This post shows you how to prevent it.

Security blanket

Some fluids have to be kept away from air. That can be tricky in a storage tank, when the fluid level can rise or fall. One answer is to use a tank-blanketing regulator.

A special K

Swagelok's K Series regulators are designed for analytical instrumentation. The K refers to the original manufacturer, Kenmac, a British company that Swagelok acquired in 2003.

Go with the flow

Swagelok's high-flow regulators are in the RHPS Series. They come in flange sizes up to 4 inches. They're designed for applications in the chemical/petrochemical, oil and gas, power, biopharmaceutical, semiconductor, and alternative fuels industries.

If Santa didn't put any Swagelok regulators under your tree this year, you can always put them on your after-Christmas shopping list. We'll be back open on Dec. 27, ready to discuss all your needs. In the meantime, enjoy the holidays and Happy New Year!

 

Topics: Regulators

Two Ways to Find the Right Size Pressure Regulator for the Job

Posted by Katie Dennis on Wed, Nov 12, 2014 @ 15:11 PM

A few simple questions is usually all you need to do, but we also have formulas

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Download the Swagelok web-catalogue, How to Size a Pressure Regulator PDF heredescribe the image

We've blogged before about the importance of selecting a regulator that's the correct size for the job. By size, we mean how much pressure and flow it is designed to handle, not the size of the end connections.

Some customers have the math skills and the desire to go through a set of precise calculations leading to the right answer. Other customers want something simpler. We can accommodate both approaches.

Five questions

For those who want to avoid most of the complexities, we typically ask some combination of five basic questions:

1. What type of regulator are you going to be using? Usually it will be a pressure-reducing regulator or a back-pressure regulator.

2. What is the inlet and outlet pressure ranges? Generally speaking, you'll want a regulator designed to operate across a range beyond the pressures you are using. "For instance, if the desired outlet pressure is 500 psi, you wouldn't want the control range operating 0 – 500 psi" says Andrew Worthington of our Sales & Service team. "You would want it rated at twice that. The middle is where you get the most accurate reading."

In regards to inlet pressure, regulators whose inlet pressure rating closely match actual system pressure show less droop and a broader ideal operating range than those whose inlet pressure rating is much higher than the actual system pressure.

3. Will you be running a gas or a liquid through it? Gasses can be compressed, but liquids can't. That makes liquids a little easier to deal with.

4. What is the operating temperature?

5. What is the flow requirement?

Then we typically refer to the flow curves for the various regulators. A flow curve is a graph that shows the range of pressures that a regulator will maintain, given certain flow rates in a system. Typically it's best for a regulator to operate in the middle of its range, where the flow curve is relatively flat. When a regulator is forced to work at either extreme of the flow curve, you risk getting a choked flow, or having the regulator operate wide open and unable to control pressure at all.

Figuring the details

But for customers who like to work the formulas, we have plenty to offer.

For liquids, we start with the fact that volume flow (Qv) through a pipe cross-section (A) in a unit of time is always constant. So, Qv = A x V (velocity). This implies that velocity must increase as the cross-section becomes smaller to maintain the same volume flow. The conclusion is that the flow rate depends only on the pressure drop. As long as the difference between P1 and P2 is the same, the flow is the same whether the system pressure is high or low.

Then we have a rule of thumb that says velocities should not exceed certain limits for different kinds of pumps. Another rule of thumb says not to exceed a velocity of 4.5m/sec for pressure above 7 bar.

For gasses, the formulas get more complex. Since density of gas changes with pressure, it's important to calculate the size of two orifices in the regulator, the seat orifice, and the outlet orifice.

That’s a lot of information to take in, and there's even more to consider, enough to fill a couple of pages. But don't worry; your Edmonton Valve & Fitting representative’s already know that information. So bring us the basics, and we'll be glad to do the math for you, or even with you.

To download the complete Swagelok web-catalogue on How to Size a Pressure Regulator, click here

Topics: Q&A, Regulators

Find Highlights on Swagelok Regulators from Previous Posts

Posted by Taryn Hardes on Wed, Aug 27, 2014 @ 12:08 PM

When we started our blog in 2012, our first post was about regulators. We keep coming back to the topic because there's plenty to say. Here are some posts worth revisiting.

  Swagelok Regulators
 

The RHPS Series Catalogues looks at the two types of RHPS series pressure regulators, the variety of models available, and features. To request your copy of this catalogue, click here. 

Sizing up regulators

With so many types and sizes of regulators in the Swagelok catalogue, a person might wonder how to figure out the right model for the job. This post starts you down the right path.

Learning curve

One of the primary tools for matching a regulator to the job is the flow curve. If you learn how to read these charts, you'll feel a lot more confident when you talk to your Swagelok representative about your needs.

Straight from the expert

On one of his visits to Edmonton Valve and Fitting, Swagelok Field Engineer Eric Kayla was kind enough to give a quick training session to our account managers and customer service representatives. It included these 7 facts about regulators.

That's creepy

"Creep" is an increase in outlet pressure that occurs when pressure escapes, even though the poppet is closed. Every regulator is susceptible to it, but there are ways to prevent it. This post tells you how.

Blanket statements

Plain old ordinary air can cause problems when it comes into contact with some fluids kept in storage tanks. How do you prevent that when the level of fluid in the tank rises and falls? The best answer is often the Tank Blanketing Regulator. This post explains why.

An analytical look

For analytical instrumentation, Swagelok offers the K Series of regulators. It's a nod to the original manufacturer, Kenmac, a British company that Swagelok acquired in 2003. This post links to the full K Series catalogue.

High flow

When Swagelok wanted to add high flow regulators to its product line, the RHPS Series was the answer. These regulators come in flange sizes up to 4 inches. The Dutch company that developed them spent more than 20 years engineering them for applications in the chemical/petrochemical, oil and gas, power, biopharmaceutical, semiconductor, and alternative fuels industries.

Of course we're not done writing about regulators. So keep checking back to see what new aspects we cover.

Topics: Regulators