Arrow takes a wider aim with A54-E engine platform

It might seem strange to consider something that has been around for decades as “new”. Considering all the changes and enhancements that Arrow Engine Co. has made to its A54 gaseous fuel engine platform, it’s hard to think of the A54-E as anything but new.

The well-known A54 engine, which has been working away for decades in wellhead compression, gas lift and other oil and gas applications, has gotten a significant makeover that firmly positions it for a greater number of 21st century applications.

Rick Harris, director of engineering for Tulsa-based Arrow, which is part of the Trimas Corp. family of businesses, said, “We originally acquired that engine from Waukesha in 1993. It’s been our number one engine over the past 27 years.

“Now we have modernized and relaunched it as a new engine model that is technology-driven, EPA-certified and with an attractive new price point. This will allow us to get into new markets and expand our current markets.

Future focus on mobile power generation manufacturers
“It’s been a compressor engine, a pump jack engine and a driver for various steady-state applications, but mobile power generation has never been an area we’ve played in.

“But now with the technology improvements, EPA certification, and significantly improved price point, Arrow has a proven industrial engine option for mobile power generation manufacturers.”

The Arrow A54-E is a 5.4 L six-cylinder natural aspirated industrial engine

The A54-E is an inline six-cylinder industrial engine with bore and stroke dimensions of 100.9mm x 118.49mm and an overall displacement of 5.4 L. Naturally aspirated, it incorporates two valves per cylinder, a pushrod-style valvetrain, replaceable cylinder sleeves and a dry air filter and spin-on oil filter. With a 17.5 qt. oil capacity, the A54-E has an oil change interval of 750 hours.

The engine is rated 68 hp (50.7 kW) continuous and 75 hp (55.9 kW) intermittent at 1800 rpm with a peak torque of 233 lb. ft. (315.9 Nm) at 900 rpm. It is certified to the USA EPA’s stationary and non-road mobile emissions standards operating on pipeline-quality natural gas, propane or 700 to 1600 Btu wellhead gas.

Harris explained, “The base A54 design is industry-proven, extremely durable and is completely rebuildable. It’s a true industrial engine.

“But before now it hasn’t been EPA certified. So with customers facing EPA challenges everywhere, we didn’t have a good cost-effective solution to offer.

“Our previous solution offering for emissions compliance was to simply bolt on an aftermarket AFR (air/fuel ratio) control system in conjunction with a big, expensive catalyst, but it wasn’t the best solution for our customers. It came with a hefty price tag and the customer had to endure the hassles of site certification typical of non-certified engines.”

Adding key system suppliers helped bring compliance and versatility
Arrow worked closely with several key system suppliers to bring the engine to compliance and bring new versatility to the package, notably Woodward and DCL. Woodward and Arrow co-operated in the development and integration of a proven ignition and air/fuel ratio control system, Woodward’s PG+ control technology.

Casey Mulder, marketing director for Fort Collins-based Woodward Inc, said, “Woodward has a 150-year pedigree of developing very robust products designed for long life and harsh environments. So we felt it was a perfect match to work with Arrow on this engine, given the A-54’s workhorse reputation and its need for reliability and long life in the field.”

The Woodward PG+ system provides a total system approach to engine control, providing air, combustion, fuel, ignition and knock control – all in a single integrated system. This integrated approach eliminates multiple control boxes, minimizes wiring complexity and simplifies the overall engine application process.

The PG+ System utilizes Woodward’s L-series industrial throttle. designed with no gears or motor commutator brushes to wear out

The PG+ electronics, valves, integrated sensors and advanced control algorithms provide the correct gas and air flow under varying conditions, enabling the engine to run at an optimal level with low emissions.

At the core of Woodward PG+ system is the Electronic Flow Regulator (EFR). Operating as part of the PG+ total system, the EFR provides full authority fuel control for precise fuel metering over a wide range of changing environmental conditions.

Mulder added, “Customers today want to run engines on just about every fuel quality imaginable, and the EFR allows just that while maintaining tight air/fuel ratio to continually keep the engine in emissions compliance.

“All components in the PG+ system are designed for extreme robustness, knowing how harsh the environmental and fuel conditions can be for industrial engines.

“We hear from many end users their frustration with light duty control systems typical in the market today that are derived from automotive components that fail frequently and require continual replacement and unplanned maintenance.

“Customers who have switched to PG+ are thrilled with the reliable performance and lower maintenance costs PG+ provides.”

Working hand-in-hand with Woodward engineering team
Developing a new engine application during the pandemic posed some potentially challenging issues for both Arrow and Woodward engineering teams. Some of the development was completed at Arrow facilities, while final calibration and EPA emissions testing was completed at the Woodward Technical Center.

Despite the challenges the teams collaborated 100% remotely and in less than five months completed the engine application and submitted all emission testing results to the EPA.

Mulder enthused, “I think this is a testament to the amazing talents and capabilities of both the Arrow and Woodward engineering teams.”

The Woodward technology enables a number of significant new capabilities for the A54-E, and the development effort with Woodward allowed Arrow to bring the updated engine to market in less than a year.

Harris said, “We’ve been working hand-in-hand with Woodward on this engine since Q4 of last year. They have been exceptional to work with and, by combining both companies’ expertise, the development cycle was not only very meticulous but extremely efficient.

Arrow Engine has made significant enhancements to its A54 gaseous-fuel engine platform, shown here in a field test application

“We’re most excited to provide an EPA-certified package with the flexibility of running on various fuels for both stationary and non-road mobile applications.

“We also placed an emphasis on providing an IoT connected engine for end users to remotely monitor their equipment. They now have that option through the use of telematics devices, that can broadcast the available J1939 data from the ECM.

“Another advantage of the A54-E is its bi-fuel capability. The new fuel system allows for automatic switching between natural gas and propane. This means our customer could connect both fuel sources and before the propane tank runs out the engine will switch to the available natural gas source, preventing down time.

“The system uses an advanced fuel quality learning strategy, so no adjustments are required. As long as the engine is getting the proper Btu content fuel, the system will perform all necessary corrections to maintain compliance and performance.”

DCL, the well-known manufacturer of aftertreatment technology, supplied the three-way catalyst.

Harris stated, “A lot of engines in this range tend to use a cheaper, automotive-style catalyst. We opted to go with a bit more industrial integral catalyst.

“It’s slightly oversized for the application, because we wanted to carry on the tradition and customer expectation of the Arrow engine being a durable and reliable product.

“DCL has a very good reputation. When I talk with potential customers about the A54-E, their first question is what fuel system are you using and the second question is what catalyst are you using?

“When responding with Woodward and DCL, the reactions have been about positive experiences with both manufacturers and they’re happy that’s who we chose.”

Introduction of an a la carte ordering experience
The A54-E engine is available with a number of options, with Arrow seeking to utilize an a la carte ordering experience for its customers. One such option is the engine control panel. Arrow’s standard engine control panel is a customized programmable color display.

A DCL three-way catalyst is utilized in the new emissions-certified Arrow Engine A54-E

Harris explained, “We wanted to provide a rugged control panel with features our customers get value out of. This panel provides relevant engine information, including engine vitals and diagnostics, as well as an intuitive menu structure for displaying and configuring set points, timers and alarms useful for automation applications.”

Other options include various engine configurations from a certified engine kit, aimed at OEM packagers to a fully enclosed power unit or stationary generator set. Other engine options include oil coolers, fans, silencers, clutches, bases, autostart systems, telematics, fuel filtration and various shut down devices.

Arrow will also provide engineered-to-order solutions for customers in niche applications or who want to maintain product continuity with an existing fleet of equipment.

The A54-E is the first of a new range of EPA-certified engines that Arrow Engine will begin launching in 2021. In the second half of the year, the company will debut the initial model in the new KP series of gaseous-fueled engines that have been in development since early 2020.

Harris declared, “I think our customers will be really excited about what the future holds for Arrow. The next wave for us will be a complete series of new engines, ranging from 24 hp to 95 hp, that we are excited about because it will continue to expand our product offering and bring greater market opportunities.” 

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