Diminishing functionality of combustion turbine components due to aging parts is a concern for plant and maintenance managers. The harmonization of each individual part of a machine is crucial to efficient operation, and that is especially true in aging 7E, 7F and 9F combustion turbines. The valves, which were originally branded as Dana-Gresen and distributed by Tri-Line Automation, have been supported and manufactured by Parker for many years. As the parts continue to age, there is increased potential for inefficiency and performance issues. So, when is the best time to take a deeper look at your vintage turbine valves?
The answer is yesterday. It’s never too early to have a replacement on hand or get your current valves serviced. If you’re too late in responding to the potential issues, your production, efficiency, and uptime will all suffer. Find out why right now is the time to inspect your turbine valves.
Plan to register for our upcoming webinar, Parker Legacy Valve Service: How to Maintain the Future of Your 7E/7F Turbine Valves.
There are three combustion turbine control valves that all plant and maintenance managers should keep on their radar:
Each valve has a different purpose, but if any of the aging valves are overlooked, they may cause issues or even unplanned shutdowns.
Gauge Selector ValvesThis valve allows for fuel pressure measurement of each supply line feeding the combustion cans. With 20 to 30 years of wear and tear from stagnant fluids or heavy cycling, the condition of this valve should be closely monitored.
There are many potential issues that may occur. First, the gauge selector handle may become hard to move. An even bigger concern involves fuel oil pressure leaking into the common port connecting the fuel pressure gauge. This type of leakage would result in the gauge always showing some amount of fuel pressure, regardless of the selector handle position. As with most elastomeric type seals, thermal and process exposure contribute to a limited seal lifespan.
This large multi-port “check valve” delivers fuel to the primary and secondary ports on each combustor can, only permitting fuel flow when actuated. Fuel isolation valves are actuated by a single-piston to ensure each combustor can get fuel at the same time. This eliminates the risks of turbine cold spots and avoids startup or fuel transfer issues. This valve also has zero internal leakage and has a limit switch to confirm the valve operation.
While there is no internal leakage to a fully functional valve, there is likely internal wear and damage due to old, dirty, and stagnant fluids, which could eventually lead to corrosion and leaking.
A new fuel isolation valve offers protection against the risk of cold spots. Contamination can cause restrictions that create an increased pressure drop across the valve, resulting in less than the desired amount of fuel being delivered to the engine. Contamination, corrosion/erosion, and heavy cycling can also cause internal leakage across the check valves and in extreme cases, external leakage.
Water Staging/Isolation ValvesThe water staging/isolation valves control water that is used for NOx reduction and combustion temperature control. They also have the same number of ports as the gas turbine has combustion cans.
The potential issues for water staging/isolation valves are identical to the fuel isolation valves. Valves with 20 to 30 years of wear are more likely to experience pressure spikes, leakage, and control issues. The longer a valve has been in service, the greater the possibility of internal wear, corrosion, and seal degradation.
Why now?
Based on the vintage of the turbines and valves and a recent spike in requests for service and overhaul, it is crucial to understand the condition of the valves at your power plant. Parker has developed a Valve Service Plan for the replacement or refurbishment of these valves scheduled around your planned outages, minimizing disruption to plant operations.
Plant and maintenance managers should begin thinking about replacing these aging valves prior to planned spring or fall outages, avoiding downtime during the year. The inspection of these valves is important to the performance of 7E, 7F and 9F combustion turbines, and the age of the valves is enough reason to assess them immediately.
The next step is to rely on Parker. We have been an experienced and trusted partner in the industry for decades, and our goal is to help you minimize downtime, create efficiencies, and increase plant output. Inspect your valves and schedule a call to discuss Parker’s Valve Service Plan with the Energy, Oil & Gas Team. Learn more on our turbine valves website.
If nothing is wrong with your valves, that’s great! But it is never a bad idea to have a known support path, contacts within Parker’s manufacturing operations, experienced field-based engineers, and spare parts on the shelf!
If you just want to learn more about the valves in your combustion turbine and the importance of their maintenance, register for our webinar: How to Maintain the Future of Your 7E/7F Turbine Valves, which takes place at 11 a.m. ET March 18.
Article contributed by James Hoke, capital projects manager, Parker Hannifin’s Energy Team, and
Mitch Eichler, business development manager, Parker Hannifin Hydraulic Valve Division
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Firefighters have one of the most dangerous and demanding jobs in the public’s eye. They are called upon to face complex fires or natural disasters to save lives or property. Innovative technology to help protect people and property is in high demand from firefighting forces around the world. This demand led Crash Rescue Equipment to team up with Parker’s Cylinder Division to design a telescoping nozzle on fire trucks that allow the nozzle to penetrate composite fibers and be placed inside small door openings or other restricted areas.
“Our Snozzle is a quick attack tool that can penetrate all current building, aircraft, automobile or train container materials including composite panels. By using Parker’s Helac hydraulic rotary actuator to position our piercing nozzle, we can quickly penetrate and maneuver into tight spaces in a variety of aviation and municipal applications,” stated Grady North, chief engineer for Crash Rescue Equipment.
Before using Parker’s Helac rotary actuator, Crash Rescue Equipment used two electric motors to position the piercing and water volume nozzles on the telescopic booms found on the fire trucks. When the object was pierced, a load was also put on the water volume nozzle, taxing the motors. The result of this overload condition caused the motors to slip and lose positioning control of the piercing nozzle.
Crash Rescue Equipment changed the overall design of the telescoping boom assembly to overcome this problem. They separated the function of the piercing nozzle from the water volume nozzle and used Parker’s helical, hydraulic rotary actuator to stow and deploy the piercing nozzle through 180 degrees on the telescopic boom. “Because of the inherent (zero-drift) features of a Parker’s Helac rotary actuator, our piercing nozzle could receive higher torque loads and hold side loads during piercing operations,” said North.
It’s the operating technology that makes Parker’s Helac hydraulic rotary actuators unique and offers a powerful combination of features – high torque and moment loads capacities, high angles of rotation and compact configurations. Sliding-spline operating technology replaces multiple components and functions as a rotating device, mounting bracket and bearing, all-in-one. This innovation converts linear piston motion into a powerful shaft rotation.
Each actuator is composed of two moving parts – the central shaft and piston. Helical spline teeth on the shaft engage matching teeth on the piston’s inside diameter. A second set of helical splines on the piston’s outside diameter mesh with the gear in the housing. When hydraulic pressure is applied to the piston, it moves axially, while the helical gearing causes the piston and shaft to rotate simultaneously.
Researching the choiceCrash Rescue Equipment looked into several electric positioning alternatives before proceeding with a hydraulic rotary actuator. They wanted to avoid adding hydraulic lines to the internal electrical flex tube if at all feasible. They began their search with electric linear cylinders, yet quickly discovered that the geometry wouldn’t fit the application and that the cylinders also needed a much higher degree of rotation. Additionally, cylinders have external rods and linkages that would increase the maintenance costs associated with particle contamination to the electric circuitry.
Electric motors were also researched. This possibility failed to offer the torque requirements or mounting strength needed for the piercing nozzle application. The selected rotary actuator provided the engineers with compact configurations, 180° of smooth rotation, and a durable, enclosed envelope without any external moving parts. It also offered torque output to 740,000 inch per pound, even though only 4,200 inch per pound of torque were needed to operate the piercing nozzle.
The Helac L20-4.5-180° rotary actuator was mounted directly onto the boom. Because of the actuator’s high radial and torque capacity, auxiliary bearings are not needed. All external forces are supported solely by the actuator.
This article was contributed by Jessica Howisey, marketing communications manager and Daniel Morgado, applications engineer, Helac Business Unit, Cylinder Division and was originally published by Pneumatics Tips Fluid Power World Resource
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Considering that more than six million people live in the Philadelphia region, government officials realized they needed a fast-response emergency river vessel with both fire fighting and rescue capabilities for any type of emergency it may encounter. Philadelphia officials turned to Derecktor Shipyards, New York, to manufacture the Independence, a 2000-Class Fireboat, which was christened in December 2007.
Established in 1947, Derecktor Shipyards builds a variety of commercial vessels and custom mega yachts for customers around the world. The waterways around the Philadelphia region pose a significant and serious set of obstacles that needed to be considered when designing and building the Independence. With regional responsibilities from as far north as Trenton, New Jersey and as far south as the Delaware Bay, the Independence would find itself in water depths as shallow as 30 inches. Furthermore, some of the waterways are very narrow, so the Independence was designed to make 360° turns.
The Independence is powered by four 825 horsepower engines, allowing it to achieve speeds of 36 knots. Its fire fighting arsenal includes a water pump capable of 5500 gallons per minute and 200 foam tank capacity. It also has a 16-ft rescue boat, and its galley can be converted into a trauma unit complete with advanced life support equipment.
However, the greatest challenge for the fireboat was its height. Many bridge structures in the area only allow vessels with an air draft of 18 feet to pass underneath. Air draft is the distance from the water surface to the upper-most point of a vessel. Therefore. keeping the air draft of the Independence less than 18 feet was imperative to its safe travel and access to all areas within its range.
Making movesTo enable the Independence to achieve an air draft of only 18 feet, a navigation tower on top of the pilot house needed to be pivoted 110°. This is accomplished using a helical rotary actuator from Parker’s Cylinder Division.
According to Joe Beckham, project manager at Derecktor Shipyards. “With the navigation mast situated on top of the pilot house, determining how to rotate it through its 110° of travel was difficult." Hydraulic cylinders and electromechanical positioning devices had been considered, but a Helac L20-15-E-FT-180 rotary actuator was specified to position the mast.
Operating technology
Helac actuators are designed to replace multiple components and function as a rotating device, mounting bracket and bearing, all-in-one. The innovative, sliding-spline operation technology of a Helac actuator converts linear piston motion into powerful shaft rotation. Each actuator is composed of a housing and two moving parts — the central shaft and piston. Helical spline teeth on the shaft engage matching teeth on the piston’s inside diameter. A second set of helical splines on the piston’s outside diameter mesh with the gear in the housing.
Rotary actuator benefitsBeckham summarized the rationale of partnering with Parker in four major points. First, the Helac rotary actuator makes better use of space than the other alternative considered. Hydraulic cylinders and electromechanical positioning devices would have required a well or cavity below the mast. This well would have protruded down into the pilot house. Considering the limited space available, the compact design of the rotary actuator made it the optimal choice.
Second, the Helac rotary actuator requires less maintenance as a positioning device than hydraulic cylinders. Sealing occurs against smooth cylindrical surfaces, effectively eliminating all leakage and holding selected positions without drift. There are no external moving parts, which eliminates the service and maintenance issues often associated with hydraulic cylinders and mechanical linkages in a marine application.
Third, this helical rotary actuator delivers high torque and 110° of smooth rotation from the limited hydraulic supply with power to spare. Achieving 110° of rotation is possible with alternative solutions. However, the L20-15 delivers up to 15,000 pounds per inch of torque and produces consistent, smooth motion from a 3,000 psi hydraulic source..
Fourth, Derecktor shipyards saved substantial installation time and cost because the L20-15 serves the double function of rotary actuator and bearing support all in one compact package. This self-contained design reduced the number of parts required of the mast assembly.
This article was contributed by Jessica Howisey, marketing communications manager and Daniel Morgado, applications engineer, Helac Business Unit, Cylinder Division and was originally published by Hydraulics & Pneumatics
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After witnessing first hand what the PowerTilt Tilting Coupler and the PowerGrip Multi-Purpose Jaw Bucket could do for a neighboring county’s public works department, Paul Stubbs, Road Supervisor with Idaho's North Latah County Highway District proposed the acquisition of PowerTilt and PowerGrip to his county commissioners. After receiving budget approval, Stubbs’ team procured the productivity-enhancing attachments they coveted, in the form of two PowerTilts and two PowerGrips for their CAT excavator fleet.
Every day poses new challenges for the North Latah County Highway District, and it was imperative to find attachments that could work to keep up with the skilled team maintaining the North Latah County infrastructure. On any given the team may need to widen roads, slope banks, clean ditches, replace culverts, remove brush or trim trees. PowerTilt and PowerGrip allow the highway district to move seamlessly between these tasks without skipping a beat. “With PowerTilt and PowerGrip we complete a variety of roadside maintenance and repair projects faster and with a better-finished appearance than before," said Stubbs.
Before using the PowerTilt and PowerGrip combination, clearing brush and trees with the cylinder-style swing coupler and thumb combination was cumbersome, lacking gripping capability when rotated and involved a significant disturbance to roadside vegetation, resulting in a less-than-tidy finished look. However, with PowerTilt and PowerGrip you can use the PowerGrip’s jaw functionality through the full range of PowerTIt’s rotation. Tree and brush removal is less invasive due to the ability to grab the brush at the base and pull it out instead of having to dig the root system out. Branches of trees can be snapped off with PowerGrip leaving the tree. This has garnered positive feedback from county residents.
Equipment operator Tom Carter agrees with Stubbs’ favorable impressions of Parker’s Helac attachments. The department switched to the PowerTilt and PowerGrip combination from their previous cylinder-style swing coupler and thumb set up and has been very pleased with the performance. PowerTiIt allows them to hold the PowerGrip Jaw Bucket at the perfect angle for sloping and ditching work without drift. PowerGrip’s multi-purpose functionality is a tremendous time-saver since it can seamlessly transition between grading with the smooth lip, clamming material to move it out of the way, to trenching like a conventional digging bucket and functioning like a thumb or grapple.
A new angle on culvert installation and repairWith the PowerTilt and PowerGrip combination and an excavator, an equipment operator can handle all steps of culvert installation or replacement more efficiently and safely than ever before. The operator angles the PowerGrip Jaw Bucket with PowerTilt and scarifies the road surface with the corner of the bucket. Then the operator simply digs out the weakened soil or substrate to the depth of the existing culvert or to the appropriate trench dimensions for the new culvert installation. When replacing an old culvert, Stubbs values the safety enhancements offered by PowerTilt and PowerGrip. “Previously, culverts were lifted and stood on end to clean them out with chains which created some potential hazards. We can now' grab the culvert with PowerGrip and rotate it with PowerTilt, dumping any loose material out, virtually eliminating the risk of an uncontrolled event," according to Stubbs. PowerTiIt and PowerGrip have quickly made their mark for the North Latah County Highway District and the team expects that their opinions of Parker's Helac attachments will only increase as they log more hours using them.
“The PowerGrip Multi-Purpose Jaw Bucket really impressed me and our team with the tremendous maneuverability of its gripping action relative to a hydraulic thumb. I would rate both PowerGrip and PowerTilt very high on all accounts."
Paul Stubbs, road supervisor
PowerTiIt is available for equipment up to 75,000 pounds in eight sizes with a standard rotation of up to 180 degrees. Each model is designed for a specific class of machinery and individually customized to fit the carrier. PowerGrip buckets are available for equipment up to 20 tons, in three sizes, with bucket width ranges from 24 inches to 48 inches in the trenching profiles and 48 inches or 60 inches in the ditching profiles.
Learn more about PowerTilt and PowerGrip on www.parker.com/cylinder
This article was contributed by Jessica Howisey, marketing communications manager and Daniel Morgado, applications engineer, Helac Business Unit, Cylinder Division.
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Modern, highly mechanized forestry practices are known for being fairly carbon-intensive. New technologies, however, are being introduced with the potential to help lessen the environmental impacts of forestry while helping the industry be even more productive.
Modern technology used in forestry
Today’s mobile forestry equipment is purpose-built to make “light work” out of timber harvesting — traditionally very heavy, difficult, and time-consuming manual labor.
Within a matter of seconds, a modern harvester — a tracked vehicle weighing up to 20 tons — can transform a standing, 60-foot pine tree into a pile of logs. Another vehicle, known as a forwarder, can then haul those logs — up to 8 tons’ worth at a time — out of the forest and to a road for further transport.
To handle this sort of heavy work, mobile technology used in forestry is typically powered by large diesel engines. The process of harvesting is very carbon-intensive. As stated in a 2018 article in the ScienceDirect Journal of Cleaner Production:
While efficiency has increased through mechanization (Berg and Karjalainen, 2003), forest operations still account for the majority of emissions along the wood value chain: in that regard, harvesting is the most critical phase, due to its large consumption of fossil fuel (Dias and Arroja, 2012, Morales et al., 2015).
Fuel consumption during harvesting operation plays an important role in the overall timber extraction process: Lijewski et al. (2017) report that the fuel consumption of CTL harvesters represents 38% of the total fuel used along the technological cycle, which is higher than that consumed during forwarding (35%) and transportation (27%).
With this challenge in mind, several approaches are being taken to help reduce the environmental impacts of forestry equipment, including the use of hybrid power and digital technology.
Download our white paper Off-Road Trends: Driving Cleaner, More Efficient and Connected Machinery, and learn what influences the advances in mobile heavy machinery.
Digital technology used in forestry
While forest industries are thought to have lagged others in the adoption of digital technology, the tide is starting to turn. Digital technology is being used to increase productivity and sustainability, as forestry companies are leveraging tools such as geographic information system (GIS) mapping, satellite imaging, 3D simulations, big data and data collection, telematics and remote diagnostics, and supply chain digitalization. All this can help mobile forestry equipment operate more efficiently and improve forest productivity, getting more done with less impact on the environment.
As a 2018 report by McKinsey states:
Advanced technology can enable lower delivered costs for wood. It also makes possible higher wood yields from a given area of forest, which is especially valuable in Western Europe and East Asia, regions where little additional forest land is available.
The report goes on to project that forestry operators stand to realize productivity increases in the range of 5% to 25%. This is similar to what operators in general agriculture have realized as that industry has made the switch to digital.
The introduction of hybrid power
One European manufacturer has developed a hybrid harvester with a diesel engine and an electric drivetrain system. Software controls each drivetrain component, enabling it to react instantly based on workload. According to the manufacturer, the hybrid system delivers up to 510 horsepower and 2,000 Nm of force at working revs. The lower fuel consumption and stable engine performance also limit the amount of exhaust and greenhouse gases released into forest ecosystems.
The promise of a lowered environmental impact
Modern technology used in forestry makes light work out of tree harvesting. Because of its reliance on diesel power, this makes forestry a carbon-intensive activity. However, newer technologies — including hybrid-electric power and digital technology — hold great promise to help lower the environmental impacts of forestry.
To learn more about the environmental impact of modern forestry equipment, read our Off-Road Trends white paper.
This article was contributed by the Hydraulics Team.
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As the wheel loader is the stalwart of the construction site, equipment manufacturers know that technological advances are important in their customers' buying decisions. Add in the stringent government regulations regarding carbon emissions and the result has been more efficient, environmentally-friendly equipment. These efforts are key to increasing profits and occur through the design of components, the addition of maintenance improvements or the integration of data insights.
One area for future innovations is the use of more hybrid technology. The integration of hybrid components for wheel loaders can positively impact the environment as well as improve fuel savings, reduced maintenance, lower repair/rebuild costs and, in some instances, increased productivity. The goals for end-customers vary. For some, zero-emissions are key; for others, it might be burning less fuel or increasing power density. We know that customers won’t sacrifice quality, reliability or durability to achieve these objectives. That’s why our electrification strategy begins and ends with our customer needs. Working with design engineers to solve complex problems requires not a single solution but a versatile approach to helping match the right product to the application. This article discusses some of the components and technology that Parker brings to the table for wheel loader applications.
Electrification and hybrid systemsWhether it is an all-electric or hybrid wheel loader, the motor design has a direct impact on the maintenance and reliability of the components. Parker’s Global Vehicle Motor (GVM) advanced electric motor is intended to be used in electric and hybrid electric vehicle traction, electro-hydraulic pumps (EHP) and auxiliary applications. High power density, compact design combined with the highest efficiencies in the market provides the key. Introduction of electric solutions allow the efficiency recovery and storage of energy which would previously be wasted. Parker offers a wide range of motors with up to over 400kW of power. With a variety of sizes, lengths and voltages up to 650V each application can be uniquely engineered to maximize a machine’s performance.
The design of the GVM means that is can be used as a motor or a generator. This feature facilitates efficient system energy recovery whether from smart system design or braking solutions. This can provide a means of reducing expensive battery costs, extend the range between charges reduce overall machine operation costs.
As machinery moves more toward electrification, sensors become increasingly important to improve efficiency. Our UTS mobile sensors eliminate the need for redundant sensors lowering your total spend on electronic controls systems. For OEMs and their customers, this means one single part can perform the many functions that formerly required many individual products. This can reduce inventory requirements, simplify installation and replacement, as well as reduce related labor costs. Further contributing to less operator fatigue and higher productivity are steer-by-wire solutions. Our steer-by-wire system consists of an input device, SIL2-class control units, display and a hydraulic directional control valve. It has on-board diagnostics and component redundancy in the event of single component failure.
The incorporation of electric components require different plumbing. Equipment with the new Diesel Exhaust Fluid (DEF) engines require after treatment, and DEF fluid requires heated hoses. Designed for heating and conveying DEF (Diesel Exhaust Fluid) throughout the SCR system on wheel loaders, our SCR hoses are specifically engineered for equipment that requires Tier IV and EPA 10 compliance.
Reducing lifecycle costs of wheel loader ownership
In addition to product selection, maintenance still plays a crucial role in reducing the lifecycle costs of owning and operating a wheel loader. Harsh working conditions, poor maintenance and abusive operation can reduce the life of the machine by half. Often, it’s the simple details that lead to premature component failure and increased lifecycle costs. Managing equipment or machinery maintenance can be a challenge for even the most capable and well-resourced organization. However, maintenance schedules can be streamlined with the utilization of an assist management system such as the Parker Tracking System (PTS). This innovative system provides fast and accurate product information, speeding replacement regardless of where or when the original component was created. Because tagged products can be replaced sight unseen, PTS eliminates the need to wait for removal before new parts can be acquired. For instance, a customer can scan the barcode on Parker’s hydraulic GlobalCore hose and immediately find out the part number, size, rating, and length of hose; end fitting sizes, and configurations; and where and when the assembly was made. Documentation of the original bill of materials ensures hose assembly replacement to exact OEM specifications and compliance with applicable industry and safety standards. This information can immediately be communicated to the nearest Parker distributor, reducing unplanned downtime to a minimum.
Machine use is equally as important as maintenance. With the evolution of IoT, construction companies can measure and run reports regarding fuel consumption, productivity, machine utilization and health and more. Our Mobile IoT solution can help businesses lower cost and energy consumption by providing data that can reduce emissions for off-road equipment.Users can customize and adjust parameters, monitor their heavy equipment’s location, component health status including real-time signals. Our solution enables organizations to create quantifiable and real-time dashboard statistics about the performance or utilization of their industrial equipment. These insights have the potential of helping users avoid unplanned downtime events through continuous monitoring with the use of alarms or analytical models.
As we look to the future of wheel loaders there is no doubt that technology will play a major role in improving efficiencies and sustainability. The thought of replacing the traditional mechanical transmission with a generator, inverter and motor will increase in popularity. It won’t be uncommon for new powertrains to utilize switch reluctance technology, which will result in up to a 25 percent overall improvement in efficiency and up to 49 percent in high production tough digging applications. Wheel loaders are becoming more fuel-efficient, automated and connected and Parker's experience in the industry helps us to deliver the right solution.
The Parker Global Mobile Systems team of application engineering experts are available to assist our customers in designing and implementing new systems to meet your application needs. Contact us for more information, or if you'd like to receive more relevant hydraulics, pneumatics and electromechanical product and technology updates for wheel loaders in your inbox, subscribe here.
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