Process Control

During the past 60 years, the use of the natural gas combined cycle (NGCC) process for electricity generation has grown to make it one of the world’s leading sources of power. Along the way, natural gas combined cycle efficiency has improved because of engineering advancement.

This blog offers an overview of NGCC. It includes a brief look at its history, covers the advantages of NGCC over other power generation types, and discusses some of the challenges engineers still are confronting as the technology moves to the future.

 

Read part 1 of our white paper- 2021 Power Generation and Renewable Energy Trends, to learn how fossil-based power generation technologies are rapidly evolving and renewable technologies are being scaled to meet the demands of the 21st-century market.

 

   
A brief history of gas turbine power 

The history of natural gas turbines to generate electric power starts in 1940. In that year, a plant in Switzerland came online and produced 4 MW of power by passing superheated gas through a turbine; a process now known as a “simple cycle.” This was the first time a natural gas turbine had been used to supply the public with electricity. Larger plants were built in the decades that followed. In 1960, a simple cycle plant in British Columbia, Canada became the first to generate 100 MW of electricity.

A year later, a newer gas technology arrived: Natural Gas Combined Cycle (NGCC). The world’s first combined-cycle power plant, a 75 MW facility in Austria, started operation in 1961. By the time of its retirement in 1974, and thanks to combined cycle efficiency improvements, NGCC had established itself as “the most efficient and low-cost route to electricity production,” according to an article in International Turbomachinery. Today, NGCC is one of the leading natural gas power technologies in the world.  

 

How NGCC works 

To understand how NGCC works, it’s helpful to understand the ways it’s different from simple cycle technology. 

In a simple cycle gas turbine plant, hot gas is burned and propelled at high pressure through a single turbine. The turning of the turbine is used to generate electricity. Wasted heat is simply lost in this design, and the overall efficiency of such a plant is approximately 35 to 40 percent. 

An NGCC plant improves on this design, leveraging that waste heat and an additional generator cycle to maximize overall plant efficiency.  

In the first cycle of an NGCC plant, natural gas is burned to directly power a generator that produces electricity. The hot exhaust that would otherwise be lost in a simple cycle plant is instead captured for a second cycle. That heat energy is delivered to a boiler and used to generate steam from water. This, in turn, is used to power a steam turbine generator that produces additional electricity. The steam then condenses back into liquid water and is recycled for further use. With these multiple cycles, overall efficiency is boosted to around 50 to 60 percent. Today’s NGCC plants range in size, with the largest producing more than 1,500 MW. 

 

Improvements to natural gas combined cycle efficiency 

NGCC technology has evolved over the years, and plants have been built with increasing capacities. Global and U.S. capacity for gas-fired electricity has continued to grow steadily in recent decades. Natural gas plants (all types) now supply more than half of the energy for both residential and commercial use, and 41% of the energy used by U.S. industries. And as consumers and industries alike become more aware of the broader impact of their energy use, they can rest easier knowing that natural gas plants produce significantly fewer emissions than the average coal-fired plant.  

 

NGCC benefits 

An article in the journal Science Direct lays out several key advantages for NGCC technology.  

• Boosted electrical efficiency. NGCC plants have an efficiency of between 50 to 60% of fuel used. This is the highest efficiency currently available among power plant generating technologies; it compares to an efficiency of 30 to 35% for a coal-fired plant. A large, simple cycle, natural gas plant has an efficiency of 35 to 40%, according to Bridgestone Associates.

• Lower capital costs. The capital cost of an NGCC plant larger than 200 MW ranges from $450 to $650 per kW. A smaller plant ranges from $650 to $1,200 per kW. Additionally, a large NGCC plant can be built in less than 24 months. 

• Lower emissions and environmental impact. NGCC plants have the lowest emissions of unburnt hydrocarbons, nitrogen oxides, and carbon monoxide of any current thermal power plant technology. NGCC plants also have a more compact footprint than other major power plant types, further lessening their impact on the environment.

• The highest recorded efficiency for an NGCC plant is 63.08%. This was achieved at the 1,190 MW Chubu Electric Nishi Nagoya plant in Japan, according to a 2018 article in POWER magazine.  

• According to another analysis, prepared in 2019 by the consulting firm Sargent & Lundy for the U.S. Energy Information Administration, a 1,100 MW NGCC plant would have an estimated capital cost of $958 per kW. A 240 MW simple cycle gas plant would have a total capital cost of $713 per kW. A 650 MW coal-fired plant without carbon capture, meanwhile, would have an estimated total capital cost of $3,676 per kW. Adding incremental levels of carbon capture technology to the coal-fired plant would increase this cost correspondingly. 

The Science Direct article also predicts that:

These (NGCC) plants will displace coal in the power generation sector by 2050, under a model scenario where industrialized nations reduce CO2 emissions by 2050 through carbon emission pricing. Large emerging economies such as Brazil, China, and India will reduce CO2 emissions by 2070. 

 

The annual energy outlook for NGCC in the US 

According to the U.S. Energy Information Administration, NGCC first surpassed coal-fired plants for producing electricity in late 2015 and early 2016 when natural gas prices were very low. This trend reversed itself when gas prices rose, until February 2018. As of 2020, NGCC is responsible for 26% of electricity generation in the U.S., making it the clear leader. With the growing number of NGCC plants and the retirement of more coal-fired plants, the technology should be the leading source of power in the U.S. for the foreseeable future.  

 

Managing NGCC operations and maintenance costs 

Compared to other types of power generation, operations and maintenance costs for NGCC plants are relatively low. Data from the International Energy Agency show that NGCC has an average O&M cost of $25 per kW. This matches solar photovoltaic ($25 per kW), and beats coal ($43 per kW), onshore wind ($46 per kW), hydropower ($53 per kW), and nuclear ($198 per kW). 

Nevertheless, plant operators are smart to take a planful approach to maintenance, especially for NGCC plants used in applications with frequent starts and stops.  

 

Rely on Parker Hannifin for NGCC plant maintenance needs 

Parker Hannifin offers a wide range of solutions for power plants. These include products for automation, filtration, fluid connections, hydraulics, instrumentation, and sealing. One utility company managing a 790 MW NGCC plant was able to increase the life of its electrohydraulic service valves from 3,100 hours to more than 60,000 hours, simply by switching to Parker's solution.

 

 To learn more about advancements in power generation, read our Power Generation and Renewable Energy Trends White Paper – Part 1.

  

This article was contributed by the Process Control Team.

 

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In onshore and offshore oil and gas, operators' demand for components that satisfy a reduction in leakage paths resulted in our designing the Monoflange valve, combining primary and secondary valves into one compact unit. Integrating piping and instrument valves into a single unit delivers cost and safety benefits to the oil and gas, petrochemical, and chemical markets.

The Monoflange has a needle valve primary and secondary rather than ball valves. The result is a lower system mass, which reduces loading and vibration stresses, further improving safety and reliability. Being smaller than a traditional double block and bleed valve, gives even more space and weight advantages. This ensures that the Monoflange valve is a cost-efficient option for both owners and operators.

 

How to safely replace a plugged Monoflange with uninterrupted production

Let's take a look step-by-step at how to safely remove a plugged Monoflange using our integrated Monoball solution to enable the processing pipeline to continue operation. For this example, the application is using a close-coupled Monoflange with an integrated Monoball. This enables the process pipeline and service to continue while the Monoflange is being serviced or replaced. This unique product combination allows the process to continue with no loss of production, increasing uptime.

 

Step 1 - To ensure the safe removal of the Monoflange valve, we will isolate the Monoball valve by turning the handle 90 degrees - this will prevent any process media from escaping to the atmosphere while the Monoflange is absent. 

 

 

 

 

Step 2 - To ensure all media is vented, open both the Monoflange block valves ( Primary and Secondary) and finally turn the vent on the Monoflange anticlockwise. This will remove the trapped volume of liquid or gas between the process and the instrument in a controlled manner. For substances such as H2S, an integral tube fitting and tube can be used to ensure safe removal.

 

 

Step 3 - Close the isolation vent on the Monoflange, two clockwise rotations. This will return the product to normal service-ready conditions. 

 

 

 

 

 

Step 4 - Remove the four top nuts and washers with a spanner/wrench. This will allow the operator to remove the Monoflange and transmitter from the Monoball for transfer to the service workshop to clean or replace the Monoflange. 

 

 

 

 

 

Step 5 - In the service workshop, the maintenance team will remove the transmitter and either clean or replace the Monoflange. 

 

 

 

 

 

 

 

Step 6 - Return the Monoflange and transmitter to the Monoball.

 

 

 

 

 

 

Step 7 - Retighten nuts with spanner/wrench.

 

 

 

 

 

 

 

Step 8 - Open the Monoball valve to return to normal working conditions. 

 

 

 

 

 

 

Watch this video and see all the steps to safely removing a plugged Monoflange valve by using a closed coupled Monoball valve arrangement. 

 

 

 

 

 

This helpful support content was contributed by the Instrumentation Products Division, Parker Hannifin 

 

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Small and mid-scale LNG plants are dramatically changing the application sphere for natural gas as an alternative fuel for transportation, both onland and for marine shipping use. They are helping drive adoption in various high horsepower applications and making gas capture and distribution from remote areas and wells without pipelines a reality.

LNG plant requirements drive need for smaller line and fittings

As the requirement for small and mid-scale LNG plants grows, so does the need for tube connection technology for smaller line sizes. In the past, connection technology was limited to either orbital welding or double ferrule compression fittings. Today, driven by cryogenic applications, there are four connection options in the less than two-inch space: instrumentation compression double ferrule fittings; instrumentation compression single ferrule fittings; O-ring face seal fittings; and permanent fittings.

Connection in a cryogenic application should focus on five critical areas:

• Safety
• Leakage and fugitive emissions
• Ease of assembly
• Longevity
• Code compliance

Safety first

Safety is critical in small and mid-scale LNG plants. In these complex plants, electricity, gas and water will often coexist in close proximity. Add cryogenic temperatures to the mix and the environment becomes extreme.

The most important rule of safety in an LNG plant is to keep the media contained. Good tube connections prevent catastrophic failure at connection points. A failure mode and effect analysis reveal the threat that a bad connection – or a poorly made one – can pose to a plant. In addition to explosion leaks, the danger of frostbite exists with cryogenic temperatures. A good connection is a first defense in preventing exposure and harm to personnel.

Leakage and fugitive emissions

Leakage of methane, a greenhouse gas -- while still not regulated -- is a major concern in LNG plants. Overall, fugitive emissions will become increasingly important; keeping hundreds and thousands of connections in an LNG plant from leaking will be key.

As a basic requirement, ensure bubble-tight connections that follow appropriate leak specifications to future-proof against fugitive emissions while not limiting solely to safe exposure levels. Apart from methane leaks, cryogenic fluid leaks can cause frostbite and major freezing hazards. A small, seemingly safe leak is also a loss of revenue and efficiency. Leak-tight connections can add up to savings and notable percentage points of efficiency.

Ease of assembly

A big challenge for small-scale, modular LNG plants is the flexibility to connect on-site to a dispensing system or a point-of-use system. This often means a lot of field connections and the capability to carry out repairs. Other times it means making certain connections at the time of installation. While welding sometimes seems to be the most straightforward strategy for a permanent joint, finding certified and trained welders may not be simple or easy.

Longevity

With the operational life of an LNG plant in the range of 15 to 25 years or more, it is critical to select corrosion-resistant, robust and reliable connection technologies that outlast the moving parts. Longevity can be achieved by choosing materials that resist corrosion from environmental sources and that are compatible with the media or fluid being transported.

Code compliance

Finally, it is essential to consider applicable codes of construction that, in some environments, may include marine standards such as those for ABS or DNV GL. Code compliance helps ensure that all the above topics are covered. Codes to consider include:

• In the US: NFPA 59A
• In Europe: EN 1473:2007 and EN 13645
• Globally: ISO (draft) 116901, ISO TC 67, ISO 18638, ISO TC 252

The end-use must take into account all possible interface points such as vehicles, tankers, vessels or rail cars to define application standards.

Connection technology challenges and advantages

• The double ferrule compression fitting is a well-known component to most fitters in the industry. A single ferrule fitting allows the use of the same skill set as a double ferrule fitting but reduces the risk of making a wrong connection since one ferrule is eliminated. Both types provide good field make-and-break capability.
• The O-ring face seal fitting and flanged tubes may be tightened and remade many times, and to set torque, provide zero-clearance tube entry. Additionally, the metal seal ensures LNG compatibility.
• Finally, the permanent fitting can replace a normally welded joint or a fitting joint that typically would never need to be reopened in the field. A permanent fitting can also be made much faster and without field orbital welding.

Better protection against fugitive emissions

In both single and double ferrule fittings, stainless steel parts that rub together under high pressure have a strong tendency to cold weld and seize, leaking to leaks and the resulting fugitive emissions.

Using fittings coated with molybdenum disulfide can avoid this problem. Solid molybdenum disulfide readily adheres to surfaces, is noted for its lubrication and anti-seizing properties, and does not squeeze out under extreme pressure. The result is low assembly torque and consistent, leak-free performance, even with repeated remakes.

Many fittings manufacturers also combat fitting leaks – and the resulting possibility of fugitive emissions – through proprietary ferrule-hardening processes designed to heighten corrosion resistance. For example, Parker treats its ASTM 316 stainless steel, single and double ferrule fittings with Suparcase®. The chemical process provides greater resistance to pitting, as well as excellent stress corrosion performance to provide longer, leak-free service life.

 

Article contributed by the Process Control Team. Original article published at LNG Industry in September 2015.  

 

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Increasing customer demand requires new process applications with needs for reliable lubrication and resistance to galling under stringent conditions of temperature, pressure, vacuum, corrosive environments, process sensitivity to contamination, product life, and maintenance requirements. The various applications within power generation and industrial and chemical processing have advanced lubrication needs. Specifically, this blog is related to the science of molybdenum disulfide coatings in compression fittings. In demanding environments, such as power generation plants, where tubing connections are exposed to stringent requirements and extremes, consistent leak-tight performance is critical and molybdenum disulfide coated fittings provide a solid solution. 

 

Lubrication evolution increases demand

Molybdenum disulfide is a naturally occurring black colored solid compound that feels slippery to the touch. It readily transfers and adheres to other solid surfaces with which it comes into contact. Its mineral form – called molybdenite – was commonly confused with graphite until late in the 1700s. Both were used for lubrication and as writing material for centuries. Wider use of molybdenite as a lubricant was impeded by naturally occurring impurities that significantly reduced its lubricating properties. Methods of purifying molybdenum disulfide and extracting molybdenum were developed late in the 19th century, and the value of molybdenum as an alloying addition to steel was quickly recognized. The demand for a domestic source of molybdenum during World War I resulted in the development of the Climax mine in Colorado, which started production in 1918 and continued into the 1990s.

The availability of high purity molybdenum disulfide spurred extensive investigations into its lubrication properties in various environments during the late ’30s and ’40s. These investigations demonstrated its superior lubrication properties and stability under extreme contact pressures and in vacuum environments. These investigations resulted in extensive applications in spacecraft.

Download our white paper Molybdenum Disulfide - The Ideal Solid Lubricant and Anti-Galling Material for a closer look into the science behind high-performance compression tube fittings required for demanding environments.

 

Exceptional lubricity

Molybdenum disulfide’s exceptional lubricity is a consequence of its unique crystal structure, which is made up of very weakly bonded lamellae. The lamellae tend to align and adhere to contact surfaces, particularly under conditions of sliding and pressure, as shown here. This “burnishing in” of the molybdenum disulfide gives it its exceptional performance life.

 

 

Since molybdenum disulfide is a solid phase, it is not “squeezed out” like liquid lubricants under conditions of extreme pressure. The lamellae are very “hard” to forces perpendicular to them. This combination of properties provides a very effective “boundary layer” to prevent the lubricated surfaces from contacting each other.

The surfaces of objects are generally rough on a microscopic scale. When two objects are in contact with each other, they actually “touch” at very small regions of contact (i.e., asperities).

 

These contact regions have considerably less area than the bulk surface area, typically in the range of 0.5 to 0.001 percent of the bulk area for a machined metal surface, and consequently, the stresses at these contact points are considerably higher than the stresses calculated for the bulk surface area. When these objects slide relative to each other the frictional forces add to the stresses at the contact points, and the resultant stresses may be sufficient to cause deformation of the contact points.

When stainless steel objects slide against each other under high load, they will “gall” or “seize” due to the deformation at the contact points. The objects will actually “cold weld” themselves to each other, which is indicated by the transfer of material from one object to the other on the sliding surfaces. This causes a very rapid increase in friction, quickly to the point that further sliding is impossible without damage to the objects. To prevent this, it is necessary to introduce an “anti-galling” or “anti-seizing” agent between the surfaces. This is a substance that can maintain separation of the surface asperities under high compressive loads – that is, to provide a “boundary layer” between the surfaces. Anti-galling materials are generally very thick grease-like substances or solid materials in powder or plated layer form. Molybdenum disulfide is an ideal anti-galling compound because of its combination of high compressive strength and its adherence (ability to fill or level) to the sliding surfaces.

There are many methods of applying molybdenum disulfide to a surface, from “high tech” techniques such as vacuum sputtering, to simply dropping loose powder between sliding surfaces. The most versatile technique is the application of the powder mixed with a binder and a carrier to form a bonded coating. The binder may be a polymeric material or several other compounds, and the carrier may be water or a volatile organic. The characteristics of the molybdenum disulfide powder, the binder, the carrier, and particularly the application process must be carefully developed and controlled to optimize the performance of a specific product. A properly developed bonded coating of molybdenum disulfide can provide exceptional lubrication performance over a temperature range up to approximately 500°C, under very high pressure and corrosive exposure conditions for extensive lifetimes.

 

Molybdenum disulfide in compression fittings

During fitting make-up, the ferrule(s) is driven forward into the body seat and tubing surface as the nut is turned per the makeup instructions. The ferrules seal at contact points with the fitting body seat and tubing surface. The fitting is carefully engineered such that the ferrule and tubing do not rotate with the nut, moving only in the axial direction. This is critical to forming a high integrity leak-free tubing connection during the first make-up and subsequent remakes. Therefore, the sliding takes place between the back of the ferrule and the flange of the nut under very high pressure. This region of contact between the nut and the ferrule must have excellent lubrication for the proper action to occur during make-up to ensure ease of assembly, low make up torques, and optimum fitting function. The nut is “pulled” against the ferrule during make-up by the threads, which are also sliding under very high pressure and require high-performance lubrication.

Stainless steel compression fittings have the additional problem of preventing galling in these areas of sliding under very high contact pressures. This requires a “boundary layer material” – a substance that maintains separation of the surfaces during sliding.

Our instrumentation engineers have developed and used a bonded molybdenum disulfide coating on the nuts of our premium CPI™ compression fitting products for 30+ years. These fittings are readily recognized in the field by the “black nut” – the molybdenum disulfide coated nut, and have been providing exceptional service in many demanding applications.

The molybdenum disulfide coating has been carefully formulated and processed to optimize the performance of the CPI™ compression fitting. This fitting, with its single ferrule and the molybdenum disulfide, coated nut, has easy initial make-up with very low torque, consistent remake, and exceptional, leak-tight performance under demanding power generation applications including pressure, temperature, corrosion exposure, and vibration.

 

One product, multiple applications

We also offer a “Moly Inside” nut for use with our CPI™ and A-LOK® compression fittings. This is an optional version of our premium compression fitting products with the molybdenum disulfide coating only where it is needed, on the inside surfaces of the nuts. This offers the same low make-up torque and consistent remake-ability of the standard CPI™ compression fitting in both the CPI™ and A-LOK® versions due to the use of molybdenum disulfide on the critical mating surfaces of the interior threads and flange of the nut, but without the molybdenum disulfide on the external surfaces to rub off onto hands, gloves, or other equipment for industries requiring a “clean” appearance.

 

Download our white paper Molybdenum Disulfide - The Ideal Solid Lubricant and Anti-Galling Material for a closer look into essential attributes of high-performance compression tube fittings required for extreme environments.

 

 

 

 

 

 

Article contributed by Kevin Burke, marketing manager, Instrumentation Products Division, Parker Hannifin.

 

 

 

 

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In the quest for a decarbonised society there is no doubt that Hydrogen as an environmentally friendly fuel source is gaining a lot of popularity to become the fuel of the future. And the hydrogen revolution is happening now. Driving the ecological transition, hydrogen-based technologies are rapidly evolving, mass entering the market and becoming part of our daily lives. From clean power generation to environmentally friendly cars, the possibilities are endless.

The transportation sector is a prime example of how hydrogen technologies are taking off and making truly sustainable mobility more tangible than ever. Heavy trucks with hydrogen-powered cells are already hitting the roads, and although developing a global hydrogen refuelling infrastructure might take several years or even decades, the commitment to hydrogen economies from governments all around the world will certainly accelerate its pace.
 

Download our white paper: Addressing the Challenge of Hydrogen Embrittlement in Metallurgy.

 

 

 

 

 

The hydrogen challenge

Hydrogen is the most abundant element in nature and its versatility can offer compelling advantages as an accessible, sustainable and efficient alternative source of energy.

However, hydrogen can be very damaging to most metallic materials, causing what is known as hydrogen damage or hydrogen attack. Hydrogen is an extremely small particle and hydrogen degradation is directly connected to its capability to be easily absorbed by metals coupled with the high mobility those particles have at microstructural level.

Nearly every metallic material can be susceptible to hydrogen damage, and there are several forms of hydrogen degradation. Hydrogen embrittlement cracking is the most common form and affects the three main areas of industries that use hydrogen:

• Production
• Transportation
• Storage

  What causes hydrogen embrittlement?

Fig. 1. Embrittlement process.

Embrittlement occurs when a material loses ductility and becomes brittle as a result of the diffusion of hydrogen into the material. The hydrogen atoms find preferential places in the structure of the material, modifying its physical properties and its mechanical behaviour. The result is a loss of ductility which makes the material more brittle and more susceptible to cracking. Hydrogen can be a silent assassin, weakening the material slowly and without any clear signs of damage, often leading to critical failure.

 

The effect of hydrogen embrittlement is determined by three main challenges:

 

• The Environment
• The Mechanics of the material
• The Microstructure characteristics of the material.

Environment

Hydrogen and stress need to be present on a susceptible material for hydrogen-assisted fracture to happen. Firstly, hydrogen absorption can happen at both production and service stages. Processes such as uncontrolled melting, electroplating or welding can promote the pre-charge of hydrogen into a given metal.

Microstructure

In terms of microstructure, and as a rule of thumb, materials that bestow high mechanical strength or show a great number of defects and inclusions are likely to be more susceptible to this type of failure. The severity of hydrogen embrittlement is also a function of the operating temperature, with low temperatures being the worst case scenario in terms of material ductility and higher temperatures in terms of hydrogen absorption rate.

The factors that can affect the quality of the microstructure are numerous and have been widely documented by the materials society. Due to the complexity of the subject, the effect of microstructure as a major contributing factor to hydrogen behaviour, cannot be evaluated in simplistic terms. Taking one variable in isolation is not enough to guarantee the quality or performance of a given component and can be misleading. For example, a material grade with a ‘perfect chemistry’ or with high levels of a particular ingredient can still result in a very low quality product.

The common consequences of improper and non-controlled material processing, heat treatment and/or manufacturing operations are high densities of undesirable phases and inclusions in the raw material. These will inevitably lead to fatal and premature hydrogen assisted cracking during service in demanding H2 environments.

Application mechanics

The mechanics of the application also play a major role. Stress states in components can be caused by the presence of residual stresses associated with certain fabrication techniques as well as stresses applied during service. Improper product design and improper installation can cause overloading of stress onto the material. All of these factors can cause premature failure of components in Hydrogen service.

Can hydrogen embrittlement be prevented?

When it comes to handling hydrogen, material and equipment selection becomes, more than ever, an essential ingredient for success.

According to the International Industry Standard ISO 15916-2015, due to the fact that most metals are susceptible to different levels of H2 embrittlement, materials of construction and suitable equipment must be carefully selected to avoid failure when hydrogen exposure is anticipated. The positive news is that hydrogen embritllement can be prevented. End users need to pay special attention to the materials of construction and the quality of the equipment that goes into their assets.

How Parker is at the front end of innovation for the hydrogen market

As a manufacturer of pressure containing equipment, Parker has decades of experience in serving hydrogen applications. Parker products are designed to minimise the risk associated with corrosion and hydrogen attack and deliver successful performance in the field. The raw materials that we use are fully traceable and closely controlled from melting stage to the finished product.

In addition, our manufacturing processes are selected to ensure minimum operating risk in hydrogen environments. As well as Stainless Steels (the prime material of choice for the H2 transportation sector), we can offer a variety of nickel alloys for a wide range of other applications.  

Parker's portfolio also includes EC-79 approved products. The EC-79 approval (the Regulation of the European parliament and the Council of 14th January 2009 on type-approval of hydrogen powered motors) is an EU normative for components and systems which are installed on hydrogen-driven vehicles. Product ranges certified to this regulation are extensively tested to guarantee the safety and performance of H2 equipment under different pressures, electric, mechanical, thermal or chemical conditions.

As a leading manufacturer in motion and control technologies Parker offers a wide range of products orientated to the hydrogen market. 

 

 

Fig. 4. Parker A-LOK® two ferrule tube fittings

EC-79 approved for use on-board hydrogen vehicles up to 350 barg pressures.

 

Download our white paper and learn the main causes of hydrogen embrittlement and best practices on how to prevent it. 

 

 

Article contributed by Clara Moyano, innovation engineer - Materials Science, Parker Hannifin, Instrumentation Products Division Europe.

 

 

 

 

 

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Of the many transport fuel choices available today, none plays a more strategic role than natural gas in having an immediate and major positive economic and environmental impact. But of the two most widely available – CNG and LNG – which is most appropriate?

 

 

  Onboard vehicle filling stations  - Compressed Natural Gas

Compressed Natural Gas (CNG ) is a fuel produced by purifying natural gas and cooling it to less than 1% of its volume and stored onboard a vehicle in a compressed gaseous state at a pressure of up to  3600 PSI. CNG is used in light-, medium, and heavy-duty vehicle applications.

  Gas transport and storage - Liquidized Natural Gas

LNG is a fuel produced by purifying natural gas and cooling it to -161°C to turn it into a liquid. LNG is suitable for trucks that require longer ranges and typically used in heavy-duty vehicles. Parker Bestobell’s cryogenic valves are widely used on road LNG trucks transporting LNG to fueling station sand storage tanks. 

 

On-board vehicle filling station - Hydrogen 

Hydrogen can be produced from fossil fuels, biomass, and water electrolysis with electricity. The environmental impact and energy efficiency of hydrogen depends on how it is produced. Hydrogen-powered vehicles work by converting compressed hydrogen from their fuel tanks into electricity that powers their engines. This process generates only water vapor and heat emissions.

  Solutions

• Fittings and tubing - Parker’s A-LOK® two ferrule fittings, CPITM single ferrule fittings and tubing provide reliable leak-free tube connections on-board CNG vehicles and at fueling stations. The unique SuparcaseTM hardened ferrule design provides superior grip and safe lifetime operation.
• CNG valves and pressure regulators - Parker’s high integrity precision ball valves Hi-Pro® and B Series, check valves and pressure regulators provide safe isolation, regulation and control onboard CNG vehicles and at fueling stations. 
• Fuel regulation module - Parker’s integrated gas regulator system, FM80 provides advanced fuel handling performance. Piston regulator design delivers better control, fewer connections, and longer range.
• Cryogenic safety relief valves - Parker Bestobell’s cryogenic safety relief valves are designed to protect LNG storage tanks or capital equipment on road-going transport trucks from damage caused by over-pressure.
• LNG Cryogenic check valves - Parker Bestobell’s cryogenic check valves with innovative loose flange bolted bonnet design allow for thermal expansion and contraction eliminating leakage and maximizing safety and performance.
• Cryogenic globe valves - Parker Bestobell’s cryogenic globe valves deliver smooth operation and reduced closing torque by use of a PTFE anti-friction disc between the valve spindle and the disc assembly.
• Fittings - Parker’s A-LOK® two ferrule fittings up to 1” size provide reliable leak-free tube connections onboard hydrogen-powered vehicles and at fueling stations. The unique SuparcaseTM hardened ferrule design provides superior grip and safe lifetime operation. EC-79 approved.
• Medium pressure valves - Parker Autoclave Engineers needle valves, check valves, filters utilize a coned-and-threaded connection design providing a leak-tight reliable connection at fueling stations in applications up to 20,000 PSI and temperatures from -73° to 316°C.
• Medium pressure tubing and fittings - Parker Autoclave Engineers medium pressure cone & thread fittings provide reliable leak-free and safe lifetime operation at fueling stations.

 

 

Alternative fuel solutions for trucks and buses contribute to a better world.

Alternative fuels (CNG, LNG, H2 ) are emerging as strong and viable alternatives to traditional fuels for HGVs for many reasons: energy security, economics and the potential to reduce emissions and noise. Parker’s solutions for reliable fuel distribution and regulation help OEM’s around the world drive towards a better future.

Contributed by the Process Control Team.

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