Which Valve Technologies Fulfill the SAE J2601 Refuelling Protocol requirements?
SAE TIR J2601 establishes safety limits and performance requirements for gaseous hydrogen fuel dispensers. The criteria include maximum fuel temperature at the dispenser nozzle, the maximum fuel flow rate, the maximum rate of pressure increase, and other performance criteria based on the cooling capability of the station’s dispenser.
There are two main valve technologies used to achieve the fuelling ramp quality according to the SAE J2601:
- Remote Controlled Pressure Regulators
Currently this is the most common technology used. The main advantages of using remote controlled pressure regulators are high accuracy, no or very limited inlet pressure dependency, fast response and an overlapped mechanical - electrical control loop with high stability.
- Remote Controlled Flow Valves
Remote controlled flow valves offer medium accuracy, a certain level of inlet pressure dependency and a sometimes unstable, but good response. Maintenance or re-adjustment is required on the sealing for the regulating stem.
Both technologies are usually air or pneumatically operated and therefore require an entire sub-station of their own including an air compressor, filter/regulators/lubricators (FRLs) and air preparation equipment, plus the associated piping and tubing. The sub system must also comply with all safety-related requirements such as ATEX, as well as being able to operate successfully in both warm and cold environments.
Reducing the number of subsystems needed provides cost and operational benefits by way of a significant reduction in the total number of components. In turn, delivering fewer potential leak points, higher component reliability and, ultimately, a less complex system design.