Differences between NGV1 and NGV2 dispensing guns

I. Basic Definitions and Execution Standards

NGV1 and NGV2 are the two major mainstream international standard interface specifications for Natural Gas Vehicle (CNG) refueling systems. They serve as the core basis for distinguishing vehicle refueling nozzles and vehicle receptacle adapters:

• NGV1: Corresponds to the CSA/ANSI NGV1 standard, designed as the refueling interface specification for traditional light-duty vehicles.

• NGV2: Corresponds to the ISO 14469 series standards, designed as the high-flow refueling interface specification for next-generation heavy-duty vehicles.

Core Essential Difference: They have different execution standards and nominal diameters (NGV1 is approx. 8mm, NGV2 is approx. 12mm). The filling flow rate of NGV2 is approximately twice that of NGV1, and their physical interfaces are completely incompatible and cannot be mixed.

II. Detailed Comparison Across Four Core Dimensions

1. Applicable Vehicles and Application Scenarios

NGV1 Refueling Nozzle: Primarily tailored for light-duty civil vehicles, specially designed for small-capacity cylinder vehicles with a wide range of applications. Mainly used for small passenger cars, private cars, taxis, light trucks, and small van trucks. Commonly applied in public natural gas refueling stations and civil standard stations, supporting both self-service and manual fueling modes. It is the mainstream compatible interface for private cars and light retrofitted vehicles.

NGV2 Refueling Nozzle: Tailored for heavy-duty commercial vehicles, optimized for large-capacity cylinders and high-frequency refueling scenarios. Primarily used for large buses, heavy-duty freight trucks, and large logistics transport vehicles. Mostly deployed in bus depots and heavy-duty truck-dedicated refueling stations to meet the high-frequency, large-volume, and rapid energy replenishment demands of commercial operating vehicles.

2. Structural Dimensions and Flow Design

NGV1 Refueling Nozzle: Compact and lightweight overall structure with a smaller flow path caliber, a nominal diameter of approximately DN6, and a standard diameter of 8mm. Suitable for small vehicles with small-capacity cylinders, offering moderate filling flow to meet the conventional refueling speed requirements of private and light-duty vehicles, free of high-pressure pressure drops or noise issues.

NGV2 Refueling Nozzle: The nozzle body and receptacle dimensions are bulkier, with a significantly expanded internal flow channel. The nominal diameter reaches DN10–DN14, with a standard diameter of 12mm. Flow performance is greatly improved, with filling efficiency being twice that of NGV1, perfectly matching the large-capacity cylinder filling needs of heavy trucks and large buses. It effectively shortens commercial vehicle refueling time and avoids flow velocity noise and throttling pressure drop caused by high-flow refueling.

3. Appearance Structure and Operation Method

NGV1 Refueling Nozzle: Resembles a traditional fuel dispenser nozzle in appearance, featuring a lightweight design, simple structure, and portability. Adopts a single-handed operation structure, push-pull sleeve, and handle-type claw design for convenient plug-and-pull and lightweight operation, suitable for civil high-frequency simple refueling scenarios. The locking mechanism uses a simple plug-and-pull, spring-loaded buckle structure suited for conventional low-pressure, low-frequency working conditions.

NGV2 Refueling Nozzle: Adopts a reinforced industrial-grade structure that is wear-resistant and impact-resistant, suitable for high-intensity commercial operating environments. Equipped with a reinforced push-lock claw mechanism for a more stable structure capable of withstanding high-pressure and high-frequency refueling operations. The mechanical locking structure is optimized for large-caliber, high-pressure conditions to eliminate high-pressure refueling detachment risks. The next-generation NGV2 has completely resolved the instability defects of earlier locking designs.

4. Interface Interchangeability and Market Popularity

Interface Interchangeability (Completely Incompatible): NGV1 and NGV2 nozzles and vehicle receptacles differ entirely in size, structure, and locking mechanism, making them physically non-interchangeable. Light-duty private cars cannot use NGV2 nozzles, and heavy-duty commercial vehicles cannot use NGV1 nozzles. Cross-specification mixing is strictly prohibited to prevent high-pressure safety hazards.

Market Popularity:

• NGV1: Mainstream in the domestic civil market, fully covering early retrofitted cars, private cars, and light taxi refueling stations with the highest penetration rate.

• NGV2: Focused on commercial vehicle dedicated scenarios, centrally applied in bus and heavy truck exclusive refueling stations, serving as the standard interface for commercial CNG vehicles.

III. Supplementary General Structural Details

Valve Core Drive Method: Both NGV1 and NGV2 adopt an insertion-push-open valve core design with consistent operating logic. The difference lies in NGV2's larger diameter, wider force-bearing area, specialized high-pressure optimization of matching seal ring structures, and superior operating feel, resulting in stronger sealing performance and pressure-bearing capacity.