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Maximizing Landfill Energy Plant Benefits with Metal Bellows Expansion Joints

Posted on July 23, 2018

Landfill waste-to-energy plants and gas-to-energy plants provide a number of benefits to the environment, to the community, and to the landfill owners and operators themselves.

The degree to which landfill energy plants provide the benefits hinges on the efficiency of the plants. More efficient gas-to-energy or waste-to-energy plants trap and eliminate more environmental hazards; provide more cost-efficient energy to the community; and generate greater revenue for the owners and operators.

The more efficient the Municipal Solid Waste landfill energy plant, the greater the benefits for everyone involved. And metal bellows expansion joints from an experienced custom provider are pivotal to the efficiency of landfill energy plants.

Gas-to-energy and waste-to-energy plants largely are turbine systems in which waste or gas is burned to generate steam and turn a turbine. These turbine-based electricity operations are inherently prone to high and fluctuating temperatures, which cause thermal damage; axial, angular, lateral and rotational movement leading to misalignment of components; as well high vibration that is transmitted along ductwork and can cause damage and misalignment.

Metal bellows expansion joints — including pipe expansion joints, stainless steel bellows, exhaust bellows, and exhaust expansion joints — are flexible and made to custom-made to mitigate the thermal, movement, and vibration damage in large industrial operations. Metal bellows expansion joints help a turbine-based electricity operation like a landfill energy plant operate at peak efficiency for maximum benefit.

In other words, metal bellows expansion joints from an experienced custom provider help ensure that the environmental, community, and owner-operator benefits of a landfill energy plant are realized to the greatest degree possible.

The Benefits of Municipal Solid Waste Landfill Energy Plants

Whether the landfill energy plant produces electricity from burning garbage or from burning the methane gas generated from the decomposition of garbage, landfills that perform such waste-to-energy operations benefit the environment by reducing greenhouse gas emissions and air pollution.

Municipal solid waste landfills are the third largest human-generated source of methane gas in the United States, according to the U.S Environmental Protection Agency, and landfills that burn methane gas for energy can prevent 60-90 percent of the methane gas from escaping into the environment — depending on the efficiency of the gas-to-energy plant.

Burning the waste itself — rather than the methane — likewise limits greenhouse gas emissions and air pollution; waste that is burned for energy is waste is that is not allowed to decompose and generate the methane gas byproduct in the first place.

There are community benefits as well. Municipal Solid Waste Landfill waste-to-energy and gas-to-energy plants create temporary construction jobs and permanent operations and maintenance jobs that keep the energy plant running as efficiently as possible. The waste-to-energy and gas-to-energy plants also provide a cost-efficient source of electricity to the community, replacing more expensive, and more environmentally-damaging, fossil fuels.

Finally, the owners and operators of landfill gas-to-energy and waste-to-energy plants benefit as well. Landfill energy plants generate revenue for owners and operators as the electricity is sold to the community. Environmental compliance costs are also reduced as the landfill energy plants represent a more cost-efficient (in fact, revenue-generating) way of capturing the emissions the landfill is already required to capture under the Clean Air Act.

Understanding Landfill Energy Plants: Challenges to Overcome for Efficiency

Understanding how landfill waste-to-energy plants operate, and the challenges inherent in the operation, is key to understanding how to operate the energy plants at top efficiency — with the help of metal bellows expansion joints or stainless steel bellows — for maximum benefit.

Most landfill energy plants use turbines to produce electricity in a high-temperature, high-vibration environment that requires metal bellows expansion joints to mitigate the damage otherwise caused by heat and vibration. (Manufacturers of expansion joints, both metal bellows and fabric expansion joints, usually are familiar with turbine-based energy plants and the thermal and vibration challenges they face. Expansion joints from Flexcom are used in turbine-based electricity generation.)

In the case of a landfill energy plant the methane byproduct of decomposed garbage, or the garbage itself, is incinerated to boil water. The boiled water creates steam, which turns a turbine to generate electricity. In the process, exhaust systems composed of heavy duty ductwork and industrial air-moving systems filter out heavy metals and toxins from the burning process.

The methane gas used as a fuel source at landfill gas-to-energy plants burns at 1950 degrees Celsius (3542 degrees Fahrenheit or 2223 Kelvin), creating extreme thermal stress and fluctuations, particularly as the turbine starts from a cold state. The extreme heating and cooling, and expansion and contraction, cause landfill energy plant components to become misaligned or fail, reducing efficiency if not leading to a critical failure that requires downtime, or worse, results in injury.

Vibrations and mechanical movement add significant additional stresses to turbine-based energy operations like landfill energy plants, creating constant stress on ductwork and its connected parts. The turbulent flow of gas through the components increases vibration as well as creating rapid shifts in gas pressure, called flutter, that can damage ductwork or cause it to become misaligned.

Furthermore, the exhaust bellow or exhaust expansion joint connecting the turbine duct and exhaust duct often represents a single point of failure. Without a metal bellows expansion joint custom engineered for the specific application, the plant can be prone to shut down at any time.

Metal Bellows for Efficient Landfill Energy

Landfill gas-to-energy and a waste-to-energy plants operate in a high-temperature, high-vibration environment that requires custom metal bellows expansion joints to compensate for the stressful environment.

Since metal bellows expansion joints are manufactured to be flexible and a custom fit for the components and ductwork that they connect, the landfill energy plant enjoys enhanced structural flexibility to compensate for the stresses of temperature, movement, and vibration.

From the beginning, such as where a pipe expansion joint compensates for movement and vibration at the point where gas is piped into the operation, to the end, such as where exhaust bellows or an exhaust expansion joint helps carry out exhaust, the landfill energy plant can be more efficient.

While metal bellows expansion joints guard against the type of damage that causes downtime, they are on a day-to-day basis guarding against the smaller movements or misalignments that allow energy to escape. In an operation that aims to leverage heat for steam and ultimately electricity, the loss of energy is the loss of output — and the loss of environmental, community, and owner-operator benefit.

Custom metal bellows expansion joints create the most efficiency and ultimately maximum benefit for the environment, community, and owner-operators of landfill energy plants.

Custom Metal Bellows for Caterpillar and Other Landfill Energy Plant Equipment

Metal bellows expansion joints from FlexCom are custom made in a variety of sizes and shapes with a ranges of metal stiffness and flexibility to fit almost any landfill gas-to-energy equipment for maximum efficiency and equipment durability.

This includes custom equipment as well as standard equipment, such as equipment from popular providers like Caterpillar, which makes equipment for landfill gas-to-energy plants (as well as equipment for traditional daily landfill operations).

FlexCom pipe expansion joints are ideal for fuel intake at landfill gas-to-energy plants, where methane gas is typically piped in as a fuel source for turbine-based electricity generation. As methane gas is piped into the system pipe expansion joints compensate for extreme pressure, movement, vibration, and abrasion to preserve adjoining components including Caterpillar equipment

Meanwhile, flexcom exhaust bellows and exhaust expansion joints preserve components in the exhaust equipment and ductwork of landfill gas-to-energy plants, compensating for extreme movement, vibration, and other stresses in systems expel carbon dioxide and other emissions.

Whether for Caterpillar landfill energy equipment or any landfill energy equipment, the key is a range of stiffness and flexibility that creates a custom-fit for almost any application. FlexCom carefully chooses a metal stiffness from stainless steel to other metals, and achieves a range of flexibility with single-ply and multi-ply expansion joints

The result is maximum durability and efficiency for intake and outtake components and landfill gas-to-energy plants as a whole.

Landfill Energy Plants: Maximizing Efficiency for Greatest Benefits

The benefits of landfill gas-to-energy and waste-to-energy plants are broad.

The degree to which the benefits are realized, however, can vary greatly based upon the efficiency of the landfill energy plant: it was pointed out, for example, that according to the U.S. EPA, the amount of methane gas captured and burned at a methane gas-to-energy plant can vary from 60 to 90 percent depending on the efficiency of the plant.

In other words, the environmental, community, and owner-operator benefits of a landfill gas-to-energy plant can be 50% greater if the plant is running at maximum efficiency. The more efficient and landfill energy plant, the more greenhouse gasses and air pollution are kept out of the environment; the more cost-effective energy is created for the community; and the more costs are controlled and revenue generated for owners and operators.

Whether gas-to-energy or waste-to-energy, landfill energy plants are high-temperature, high-vibration turbine operations that benefit from the heat and damage mitigation of custom metal bellows expansion joints. Custom metal bellows expansion joints — including stainless steel bellows, pipe expansion joints, exhaust bellows and exhaust expansion joints — help ensure the plant minimizes environmental impacts, produces the most cost-effective electricity, and generates the most income.

Landfill energy plants provide benefits to the environment, community, and owners — and custom metal bellows expansion joints maximize the benefits.

For Industrial Air-Moving, Fan Isolation Joints Take Care of Fans

Posted on January 15, 2018

You need to take care of the fans.

It’s true in any line of work — you need to take care of the most enthusiastic customers and colleagues. Yet nowhere is taking care of fans more important than in the business of heavy-duty industrial blowers, industrial air-moving equipment, and industrial fans.

Industrial fan manufacturers who want to provide customers the greatest durability, performance, and safety for industrial-air moving installations can provide installations that include fan isolation joints from an experienced custom manufacturer.

Whether fabric expansion joints, metal bellows expansion joints, or composite expansion joints, fan isolation joints are critical for the lifetime value of heavy-duty air-moving equipment.

Centrifugal, Axial, Radial — You Have All Kinds of Fans.

Whether the air-moving installation includes centrifugal fans, axial fans, radial fans, or custom-engineered fans, custom fan isolation joints are essential to the efficiency and longevity of heavy-duty industrial fans, blowers, and ductwork.

Heavy-duty air-moving equipment installations require custom fabric expansion joints or metal bellows expansion joints – fan isolation joints that provide the structural flexibility to withstand vibration, and movement day after day, month after month, year after year.

Heavy-duty air-moving installations with poorly designed fan isolation joints, or lacking fan isolation joints, are inherently rigid and more prone to damage from vibration. Particularly in the case of industrial air-moving equipment, rigid structures are prone to damage from vibration.

Fan isolation joints are the solution. Expansion joints for fans and blowers help isolate heavy-duty fans from the fixed portions of the industrial air-moving installation such as rigid ductwork, the parts most prone to vibration or movement damage.

Heavy-Duty Air-Moving Equipment Needs a Heavy-Duty Solution

Heavy-duty air-moving equipment is just that: heavy-duty. And that causes heavy-duty vibration.

Expansion joints for fans and blowers compensate by deflecting axial movement, lateral movement, bi-directional movement, angular movement, torsional movement, and combinations of these movements. The movements otherwise cause damage to fixed portions of air-moving equipment, such as piping and ducts.

Fan isolation joints from FlexCom are accustomed to heavy-duty. For example, FlexCom expansion joints are used in the dynamometer cells where Indianapolis 500-winning IndyCar engines are tested.

The “dyno” cells feature exhaust systems that included power-ducted fans and ductwork that expel air and fumes at more than 1 million cubic feet per minute. (The heat is extreme as well with the racecar engines generating more than 1 million BTUs per hour. FlexCom fan isolation joints can withstand temperatures of 600 degrees Fahrenheit.

Flexibility is the key to avoiding vibration damage. Heavy-duty systems require expansion joints proven to hold up to heavy-duty vibration.

Fan Isolation Joints with Sound Attenuation Leaves the Noisy Fans Behind

Aside from movement and damage, vibration caused by high-powered fans creates another problem for industrial air-moving installations: noise.

Custom fan isolation joints combined with sound attenuation pillows help reduce noise from industrial air-moving equipment and other industrial installations.

When sound attenuation was needed at a more than 60-year-old power plant outside of Las Vegas, for example, FlexCom expansion joints were installed with sound pillows to reduce noise caused by high-vibration plant operations.

Isolate Industrial Fans and Blowers

Heavy duty air-moving equipment is used in hundreds of industries across thousands of applications, from simple industrial ventilation to heavy duty pollution control.

In ducted-air systems, flue systems, damper systems, and almost any system that incorporates industrial fans and blowers, high-quality fan isolation joints are essential. Fan isolation joints from an experienced custom manufacturer mitigate vibration damage and are critical for the durability, performance, and safety of industrial air-moving systems.

Expansion joints isolate industrial fans and blowers from rigid ductwork and piping so that heavy-duty air-moving system avoid can deflect vibration that otherwise would lead to reduced efficiency, downtime, increased maintenance costs and liability.

Efficiency: Even the slightest gap or misalignment caused by movement represents reduced efficiency. For example, in a system such as a Heat Recovery Steam Generator that leverages heat for steam, for example, heat that escapes through even minor misalignment ultimately represents a loss of output.
Downtime: Beyond vibration damage that reduces efficiency is vibration damage that causes downtime – the ultimate loss of efficiency.
Liability: Particularly for industrial air-moving installations that exhaust dangerous gases or fumes, vibration damage is a liability that can cause serious injury or death. In the IndyCar dynamometer cells, for example, FlexCom custom expansion joints are part of an exhaust system responsible removing high-levels of carbon monoxide from an enclosed working environment.

Giving the Fans What They Need

Fan isolation joints from an experienced custom manufacturer perform an indispensable role in the durability, performance, and safety of not just heavy-duty industrial fans and blowers but also the industrial air-moving system in which they reside.

The team at FlexCom has honed its expertise in fan isolation joints since 1991, providing custom metal bellows expansion joints and custom fabric expansion joints that are tested and proven to perform in heavy-duty environments.

FlexCom is here to care for the fans.

Metal Bellows Expansion Joints from FlexCom Help IndyCar Manufacturer to Finish Line

Posted on November 6, 2017

In an industry where success rides on machine performance, teams trust their machines to FlexCom.

A major manufacturer of IndyCar and FomulaOne racing engines relies on FlexCom custom metal bellows expansion joints at their dynamometer test cells, where racecar engines are tested to see if they have what it takes to compete at world-class levels.

The engines are tested at the “dyno” cells to determine how optimally they can propel a 1,800-pound vehicle at as many as 240 miles per hour for approximately three hours or more at a time.

Ideally the engines wouldn’t need to run for quite three hours if they are to beat the best times at the Greatest Spectacle of Racing. Regardless, testing engines to such extremes creates some equally extreme conditions that can only be controlled in engine dynamometer cells with top-flight exhaust systems and ductwork.

Indoors dynamometer cells typically include stainless steel flexible exhaust tubing systems, or other metal exhaust systems, that incorporate custom metal bellows expansion joints to mitigate the extreme conditions.

Dynamometer test cells experience extreme heat and other conditions that must be controlled by machinery befitting the IndyCar 500 Champion-caliber engines that they’re built to test. The engine must be at its best in front of 300,000 spectators at the Indianapolis Motor Speedway, and that means it first needs trial in the best testing environment.

In Dyno Cells, You Must Take the Heat

With high-performance motors running on what can be close to a 24-7-365 basis indoors, dyno cells are a site of extreme heat generation.

From the exposed engine surfaces, exhaust, and cooling systems, a racecar engine can generate more than 1 million BTUs per hour. And in a dynamometer cell the heat is usually generated indoors where it cannot freely escape on its own.

A high-powered exhaust system like a stainless steel flexible exhaust tubing system removes heat from the dyno cell, but the exhaust system in the engine dynamometer cell will experience heating extremes itself. Heat is one of the greatest sources of stress in ductwork, causing metallic elements to expand and become misaligned.

Misaligned ducts will not expel heat at intended levels, creating a hotter-than-intended dynamometer cell that makes accurate testing impossible. With severe misalignment or damage, the dyno cell can become inoperable or dangerous, requiring costly repairs or downtime.

Custom metal bellows compensate for the extreme heat by providing flexibility. Rigid ductwork that normally would become misaligned by consistent exposure to 1 million BTUS per hour, when augmented with custom metal bellows expansion joints, instead provide the flexibility to expand and contract in accordance with the temperature without causing misalignment.

FlexCom metal bellows expansion joints compensate for temperatures as high as 2,500 degrees Fahrenheit. It’s a grade required for testing engines that are intended to cross the Brickyard finish line first.

Movement and Vibration in Engine Dynamometer Cells Can Be Damaging, Dangerous

Heat isn’t the only factor that can lead to misalignment and other damage in dynamometer test cell ductwork, even at world-class racecar engine testing facilities. Stainless steel flexible exhaust tubing systems needs to compensate for movement and vibration as well.

The ductwork and exhaust system are high-powered in their own right. They typically include hoods, dampers, and high-powered power-ducted fans that expel air and fumes at more than 1 million cubic feet per minute. For the highest powered engines, exhaustion may need to occur at more than 1.5 million CFM.

It takes high power to clear the engine dynamometer cell of hot air and keep temperatures ambient, and the high-powered fans and components can cause ductwork to move and misalign. Constant vibrations reverberating along the ductwork eventually reduce operating efficiency, damage components and increase operating and maintenance costs.

The answer to the persistent movement and vibration is custom metal bellows expansion joint. Metal bellows expansion joints compensate for axial, angular, lateral and rotational movement and combinations of these movements, and also are designed for specific load requirements that compensate for vibration without sacrificing load tolerance, thrust resistance or joint reliability.

Carbon monoxide is another critical consideration in dynanometer cells and their exhaust systems. The danger of running car engine in an enclosed garage for only a few minutes is commonly known. At racecar engine testing facilities, even more powerful engines run in an enclosed space for much greater periods of time.

Carbon monoxide extraction is of paramount concern, and it relies on the same ductwork. Custom metal bellows expansion joints become of paramount importance to compensate for heat, movement, and vibration that otherwise would cause damage and misalignment that allows carbon monoxide to escape the system in unintended ways.

The movement and vibration that racecar engine manufacturers want to focus on are the movement of the IndyCar and the vibration powerful engine that propels it along the racetrack. At the engine dynamometer cell, they’re happy to let movement and vibration be the concern of custom metal bellows expansion joints from an experience provider like FlexCom.

Even A Little Bit of Damage Can Make Accurate Testing Impossible

No two IndyCar or FormulaOne races are held under identical conditions, so racecar engine manufacturers need to test engines under a great range of conditions.

The dyno cells manufacturer need to control air pressure, air temperature, and humidity to simulate the conditions of all the various environments the engine might run, ensuring the engine performs optimally for each. The engine needs to perform just as well in 55 degrees at 1,600 feet of elevation in a place such as Denver as it does in 95 degrees at 45 feet of elevation in a place such as St. Petersburg, Fla.

Damage to engine dynamometer cell ductwork makes precision testing impossible. Ducts even slightly misaligned or damaged by heat, movement, or vibration begin to diminish the capacity to control pressure, temperature, and humidity creating unintended variation in condition. In short, damaged ducts throw off the tests.

In order for an IndyCar to have a shot at the Borg-Warner Trophy, it needs an engine vigorously proven in the testing environment. It’s important to have custom metal bellows expansion joints that compensate for heat, movement, and vibration so that precision testing controls remain in place.

It Does an Engine Good

The process of getting a driver a jug of milk in the winner’s circle at the Indianapolis 500 starts well before the green flag waives. It starts in research and development, with engine prototypes running in world-class testing facilities, and with sourcing the right parts for a champion.

At every step of the way, success rides not just on human performance but machine performance. The ability to work with the best machines and parts at every step of the way is critical to auto racing success.

That’s why an IndyCar and FormulaOne engine manufacturer relies on FlexCom, experts in industrial expansion joints since 1991. FlexCom designs and builds each metal bellows to your specifications from stainless steel to handle pressure up to 300 psi, temperature loads up to 2500°F, and the transfer of liquids through joints and surrounding piping.

Well before the gentlemen are encouraged to start their engines, custom metal bellows expansion joints from FlexCom are busy at world-class testing facilities to help ensure the best possible result when the checkered flag flies.

HRSGs Designed with Custom Expansion Joint Technology from an Experienced Manufacturer Lead to Greater Operational Efficiency

Posted on August 29, 2017

When it comes to equipping a sophisticated machine like a Heat Recovery Steam Generator with damage-mitigating expansion joints, a sophisticated, experienced manufacturer matters.

Professionals know that Custom Industrial Expansion Joints are critical for the energy efficiency, operational efficiency, and cost efficiency of Heat Recovery Steam Generators (HRSGs) due to their strong ability to mitigate damage caused by extreme temperature changes and other damage incurred over time.

Expansion joints from un-established or inexperienced manufacturers who fail to produce expansion joints specific to the application and tailored for the project can cause significant downtime and loss of efficiency due to damage over time.

An HRSG is not only an intricate machine with sophisticated components, but it is by its nature highly susceptible to damage from temperature-induced expansion and contraction. With sub-optimal expansion joints, over time, the repeated expansion and contraction due to extreme heating and cooling will damage components such as the economizer, evaporator, superheater and water preheater and the structures that connect them.

To mitigate the inevitable temperature-induced damage, a Heat Recovery Steam Generator design should include Custom Industrial Expansion Joints such as Metal Bellows Expansion Joints or Fabric Expansion Joints from an experienced manufacturer. These will give the HRSG maximum structural flexibility to better withstand expansion and contraction. Ultimately, Custom Industrial Expansion Joints from an experienced manufacturer will reduce maintenance and operational costs and boost efficiency.

A Heat Recovery Steam Generator design with sub-optimal Custom Industrial Expansion Joints invites inherent structural rigidity, which exacerbates the damage the temperature-induced expansion and contraction. Without Metal Bellows Expansion Joints or Custom Industrial Expansion Joints from an experienced manufacturer, however, the structure will not have maximum flexibility to expand and contract as the temperature changes and the structure will deteriorate. The same can be said for other structural damage over time such as damage from pressure, movement and vibration.

Flexcom has close to 25 years of experience manufacturing Industrial Expansion Joints and chooses the best configuration and materials for a given application. The expansion joints are custom, and Flexcom engineers work with the customer to ensure the joints meet the customer specifications and the machine as a whole – the specifications that will allow maximum flexibility within the design of the HRSG and therefore the most uptime and efficiency.

Second-rate Custom Industrial Expansion Joints will ultimately result in a loss of energy efficiency that, in turn, will result in a loss of operational and cost efficiency. Even small cracks or separations in a Heat Recovery Steam Generator’s components or ducts will allow heat to escape.

In an operation that aims to leverage heat for steam, the loss of heat is the loss of output. When heat escapes, either the output (and the value that can be derived from it) is diminished or the operator must increase costs to generate more heat to replace what is lost. In the plainest terms: without Industrial Expansion Joints from an experienced, custom manufacturer, either output goes down or input goes up.

The HRSG owner or operator may repair damage, but also at a cost. Moderate-to-severe damage may require not just the hard cost of the repair but also the opportunity cost of downtime during which the Heat Recovery Steam Generator is producing nothing at all. The most severe damage, meanwhile, may become a steep liability for safety reasons.

Whether a Vertical HRSG or a Horizontal HRSG, the more sophisticated the Heat Recovery Steam Generator, the greater the need for an experienced, Custom Industrial Expansion Joint manufacturer. Single-pressure HRSGs feature one steam drum and a constant pressure. Double-pressure HSRGs and Triple-pressure HSRGs, however, bring additional steam drums and varied pressure, meaning more pieces subject to extreme temperature change. Similarly, a Heat Recover Steam Generator that relies upon duct firing for supplement heating during peak periods also adds greater sophistication and concern for damage, as well as a greater need for optimal expansion joints.

A Once-Through Steam Generator (OTSG), while simplified in many ways due to reduced variables and structural components, also benefits greatly from Custom Industrial Expansion Joints. The OTSG design relies upon sections being allowed to expand or contract based on the temperature, and Custom Industrial Expansion Joints such as Metal Bellows Expansion Joints or Fabric Expansion Joints are an ideal choice to provide the structural flexibility to allow this to happen.

By reducing damage caused by the extreme heating and cooling inherent in Heat Recovery Steam Generators, Custom Industrial Expansion Joints from an experienced manufacturer improve the energy, operational and cost efficiency in HSRGs. By enabling the maximum structural flexibility for pieces to expand and contract due to temperature, damage is reduced resulting in greater energy efficiency and greater retention of heat.

Operational efficiency is enhanced as the flexible structure avoids repairs and liability for greater uptime. And cost efficiency is enhanced due to reduced maintenance and repair costs, reduced need for increased input, and less reduction in valuable output.

Expansion Joint Challenges In Gas Turbine Exhaust Applications

Posted on June 5, 2017

Designing an effective custom expansion joint for a GTX (Gas Turbine Exhaust) application requires strict attention to a number of unique engineering problems. Typically installed in the vital space between the turbine duct and exhaust duct, a GTX expansion joint represents a single point of failure – if the joint fails, the plant ceases to operate as the turbine must be shut down. Therefore, when FlexCom engineers are tasked to design a custom expansion joint for a gas turbine exhaust system, we expect to face certain challenges common to most gas turbine applications, but unique compared to other industrial facilities.

Heat stress poses an intense issue to gas turbines, since the thermal state of a GTX system fluctuates severely during the course of turbine operation – particularly as the turbine starts. A gas turbine initiates from a cold state to extreme heat very quickly, subjecting an expansion joint installed on the exhaust outlet flanges to thermal shock. If the joint is not adequately protected against these rapid shifts in thermal stress, the heat will damage the joint and ultimately cause it to fail.

In addition to heat, vibrations and mechanical movement add significant stresses to an operating GTX expansion joint. As turbines and connected ductwork assemblies increase in size, power and temperature output, so too do they produce greater levels of duct movement and overall metallic vibrations.

The turbulent flow of exhaust gas through the joint additionally increases vibration – as well as “flutter”, rapid shifts in gas pressure that can damage an unprotected fabric joint. These mechanical stresses can cause significant damage to an inadequately designed joint in a relatively short amount of time.

For hot-to-hot configurations (one in which both flanges must operate at the exhaust gas temperature), we also recommend including an accumulation pillow in the custom joint design. A pillow will reduce the overall temperature of the joint, as well as limit vibration transmission to the turbine outlet flange and help absorb ductwork movement stresses in these very high temperature environments.

Custom design of a gas turbine exhaust (GTX) expansion joint requires a special level of engineering precision, as well as specialized expertise in compensating for the extreme stresses present in this type of exhaust ductwork. Don’t risk your gas turbine operation on a lesser quality product – call FlexCom offices today and let us show you how our custom designs deliver superior performance.

NV Energy Case Study

Posted on March 10, 2015

Customer: NV Energy • Las Vegas, NV

NV Energy, Inc. provides electricity and natural gas to more than two million customers throughout Nevada and parts of California. The company’s service area covers approximately 54,500 square miles.

Challenge

The Edward W. Clark Generating Station, dating back to 1954, is the oldest steam-generated power plant in Nevada. Today, it is a multi-technology natural gas-fueled power-generating complex that includes a total of 19 gas-fired Pratt & Whitney turbines with Selective Catalytic Reduction (SCR) exhaust systems. The station is located just a few miles from the Las Vegas Strip and supplies much of the power for the city.

FlexCom was tasked with developing custom fabric expansion joints that could address several challenges:

internal operating temperatures of more than 900°F;
sudden and powerful rise in temperature in a very short period of time, putting great stress on equipment, compensation joints and connected pipes;
particulate contamination in the exhaust flow;
noise pollution generated by high vibration plant operations;
keeping the joint’s external skin temperature to within Occupational Safety and Health Administration (OSHA) requirements.

Solution

Based on NV Energy’s specifications, FlexCom designed and built composite fabric expansion joints to address all design requirements:

Frames were made from A387 chrome molybdenum steel composite, a custom alloy that provides high temperature and thermal shock resistance;
ChemShield^®, a composite material made from polytetrafluoroethylene (PTFE) thermoplastic film laminated to a PTFE-coated fiberglass cloth, provided excellent temperature and pressure tolerance and a surface that is inert to nearly all chemicals and solvents;
Ceramic fabric accumulation pillows ensured superior abrasion resistance and reduced exterior temperatures;
Vinyl joint covers further reduced exhaust noise and joint surface temperature.

When you have a demanding application, turn to the professionals at FlexCom for all your custom industrial expansion joint needs.

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Air Liquide Case Study

Posted on March 10, 2015

Customer: Air Liquide Inc. • Houston, TX

Air Liquide Inc., located in 80 countries, is a world leader in gases, technologies and services for industry and health. Air Liquide has more than 5,000 U.S. employees, over 200 locations including more than 140 industrial gas plants and approximately 2,000 miles of pipeline.

Challenge

Air Liquide’s Hydrogen Manufacturing Facilities in El Segundo, California and Pasadena, Texas, are the first of their kind to be built in the United States. Each is designed to create up to 90 million cubic feet of hydrogen per day, used to supply nearby oil refineries. Air Liquide turned to FlexCom for a variety of industrial expansion joints, in sizes up to 25 feet in diameter and capable of compensating for regular steam exhaust above 1000°F.

Solution

FlexCom designed and fabricated close to 80 percent of the industrial expansion joints in Air Liquide’s hydrogen plants in El Segundo and Pasadena, including flexible fabric expansion joints and composite fabric expansion joints.

Flexible fabric expansion joints provided a cost effective, low maintenance solution. These fabric-only joints are relatively lightweight and easy to install. They are constructed of ChemShield^®, a Teflon^®-coated, high strength fiberglass cloth that is laminated to a sheet of pure Teflon, providing necessary heat tolerance.
Composite fabric expansion joints were built for larger outlets, measuring 25-feet by 13-feet. With the same protective features of the flexible fabric expansion joints, the composite fabric expansion joints have heavy-duty stainless steel frames for additional structural integrity.

Turn to the professionals at FlexCom for all your custom industrial expansion joint needs. We provide cost-effective, reliable solutions for even the most challenging environments.

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Custom Fabric Expansion Joints

FlexCom’s composite fabric expansion joints tolerate heat stresses and pressure loads and provide movement compensation. Our flexible fabric expansion joints are a lightweight, economical option for low pressure and moderate heat applications.

About Fabric Expansion Joints »

Metal Bellows

FlexCom’s custom metal bellows are made from high quality alloys and handle pressure up to 300 psi, temperature loads up to 2500°F and the transfer of liquids through joints and surrounding piping.

About Metal Bellows »

When Connections Matter, FlexCom Delivers

6864 Chrisphalt Drive • Bath, PA 18014 • 888-376-FLEX • 610-837-3812 • sales@flexcomonline.com