To stay at the forefront of the competitive transportation markets, fleet managers are turning to alternative fuels that meet the environmental and economic needs of today and in the future.
Natural gas (NG) is widely recognized as a fuel that offers high potential to offset society’s concerns about pollution, climate change and depletion of natural resources — it produces fewer greenhouse gas emissions than gasoline or diesel, and is safer, with a low chance of flammability.
NG engine availability is increasing and offers longer vehicle life with less long-term expense for the consumer. As a result, more fleet operators are choosing cleaner-burning natural gas as a fuel choice for trucks and transit buses.
Most energy outlooks predict significant growth in the use of natural gas for transportation vehicles. According to the U.S. Energy Information Administration, strong increases are projected for the natural gas share of total energy:
- Large trucks from 1% in 2012 to 15% by 2040
- 50% of bus energy will be natural gas by 2040
- 17% of freight rail will be natural gas by 2040
Types of gas
Compressed natural gas (CNG), liquefied natural gas (LNG) and liquefied petroleum gas (LPG) are three forms of natural gas used in various types of vehicles and mobile equipment. Each has its own unique characteristics making its suitability specific to different applications.
CNG applications include mobile (on vehicle) and infrastructure (fueling station). CNG is used in light-, medium-, and heavy-duty applications. From the refueling receptacle to the engine compartment, high-quality CNG components make a noticeable difference in performance.
LNG is suitable for heavy-duty vehicles, locomotives and marine vessels that require longer ranges because the liquid is denser than gas (CNG) and, therefore, more energy can be stored by volume in a given tank. However, because LNG is stored at extremely cold temperatures and requires ultra-fine filtration, it is important to choose components that accommodate these requirements.
LPG is used worldwide for propane-powered mobile solutions and a wide variety of industrial and commercial LPG/propane delivery and supply applications.
Choosing components for NG applications
When selecting components for NG applications, manufacturers should consider the following:
- The specific temperature required by the application
- The need for stable durability in the presence of gases such as methane, ethane, propane, and CO2
- Ability to withstand high-flow pressure conditions when required
- Certification and/or testing to meet the applicable recognized standards
Certifications and testing
Standards and certifications governing the design of components used for natural gas vehicles and refueling stations have been established to provide assurance that components and systems have been objectively evaluated for their function and safe operation in the intended application.
- The importance of testing and validation
- Descriptions and contact information for certifying organizations
- Types of certifications for on vehicle and fueling station products
- Information on CNG inspector training and certification programs
Benefits of using certified, listed products
Safety and performance are the primary drivers for products carrying certification to defined standards. These overlaying priorities influence the entire supply chain from design to final installation and operation. By maintaining a consistent standard, manufacturers, as well as customers, gain the peace of mind that the components and systems have been tested and monitored in their intended area of application, and have met the pre-defined criteria for safe use and performance.
“There is always a risk in using untested, unvalidated components in an NGV application. You face safety concerns as to whether the component can handle the pressure extremes and temperature variations. The biggest risk of using uncertified components is leakage. If you use a component that has not gone through the rigors of certification, you will not have the assessment that the component will not leak and become a safety hazard,”
— Ken Loewenthal, product manager, alternative vehicle fueling, CSA Group
Risks of using non-certified products
Financial performance: Although non-certified components may present material cost savings, using them could result in financial risks. Any material savings would be lost with even one safety issue caused by a leak or other failure. The cost of replacement products, downtime, and potential liability would be substantial.
Reputation: The failure of a non-certified component could reflect negatively on the manufacturer suggesting a lack of quality, disregard for standards, and low priority placed on safety.
Productivity: Certifications help ensure components safely perform in the application. Using non-certified components may delay approval of the equipment by Authorities Having Jurisdiction (AHJ) inspectors if they think additional on-site testing is needed.
"Certification marks offer peace of mind to retailers, regulators, consumers and end users the world over by indicating that your products have been independently tested and have met the required standards for safety and performance"
— CSA Group
Organizations and associations
For safety and performance standards, several organizations provide certifications, requirements, specifications and guidelines to verify that natural gas vehicle fuel systems and components offer the highest quality and reliability. These include:
- CSA Group
- Underwriters Laboratories (UL)
- National Fire Protection Organization (NFPA)
- International Organization for Standardization (ISO)
- Economic Commission for Europe (ECE)
Comprehensive range of fully certified products
Parker offers the most comprehensive range of fully-certified, multi-technology systems and components for natural gas vehicles and fueling stations. Our proven subsystems and components in fluid management, motion and fluid control, filtration, and temperature control provide NG solutions that offer improved service life, reduced risk, and greater value to customers. Here’s a snapshot of some of our product solutions:
High-pressure particulate filter FFC-112 is ideal for CNG-powered vehicles, such as airport shuttles and taxis, to protect critical engine components from contaminants in CNG fuel. The machined aluminum housing is anodized to enhance durability and its robust yet small, lightweight size allows for versatile installation and easy servicing. Both 1/4” NPT and 9/16” SAE connections are available on this 3600 PSIG rated assembly.
FM80 fuel regulation module is a fully integrated CNG flow control and regulation system for medium and heavy-duty vehicles and is constructed of robust anodized aluminum, a high-grade low-sulphur “Vericlean” stainless steel poppet, and Parker VG109 seals. Integrated internal regulator components, with fewer connections, work together to eliminate fuel line failures due to freezing, dampen flow induced vibration, reduce drop at high flow, and extend cycle life. Features include an advanced metal piston style regulator, coalescing filters, pressure sensors, lock-off solenoid valve, heat exchanger, and low-pressure relief valve all in one compact body. Exceeds industry standards for leakage and safety and is certified to ANSI NGV3.1 / CSA 12.3.
5CNG high-pressure CNG hose is specially developed for the conveyance of compressed natural gas. It is constructed of an electrically conductive nylon core designed to dissipate static build up and fiber reinforcement for maximum pressure and flexibility. The polyurethane jacket provides abrasion resistance and protection from outdoor elements including ultraviolet light. Conforms to and is listed per NFPA 52, ANSI/ CSA NGV 4.2, CSA 12.52, Class A & D Certificate # 1053249 (hoses for natural gas dispensing systems).
CNG fueling station
Seal-Lok™ for CNG o-ring face seal (ORFS Fittings) offers a leak-free design and a rugged construction to make them optimal for use in situations with high-pressure, vibration and impulse environments. Seal- Lok™ for CNG provides a zero clearance fitting system, which allows for ease of assembly in tight installation areas. Seal-Lok™ for CNG applications has been tested and certified by TUV according to the following standards: ECE R110 regulation (Economic Commission for Europe), ANSI NGV 3.1-2012/CSA 12.3-2012 (Natural Gas Vehicles/ Canadian Standards Association), and ISO 15500.
LNG on vehicle and fueling station
Metal LNG hose is designed for extreme chemical and temperature applications, Parker’s metal hose offers excellent chemical resistance with zero permeation. Hydro-formed design yields a uniform wall thickness, promoting even distribution of stress during flexing and reduces concentrated residual stress. Maintains its integrity up to 1200°F.
As natural gas technology continues to advance, manufacturers are motivated by their desire for quality and safety to verify that their components are tested and in compliance with the most current standards. Understanding applicable natural gas certifications provides assurance to both manufacturers and consumers that components and systems will perform safely and reliably.
This post was contributed by Steve Duricky, business development manager, Parker Hannifin