Key Factors to Consider When Purchasing a Fire Truck
When selecting a fire truck, it is essential to evaluate the following technical parameters and performance indicators:
1. Maximum Permissible Gross Weight of the Chassis
This refers to the maximum allowable total weight of the chassis as specified by the chassis manufacturer (excluding the spare tire). It is a key indicator of the load-bearing capacity of the chassis.
2. Power-to-Weight Ratio (kW/t)
The power-to-weight ratio is the ratio of the engine’s maximum net power to the vehicle's maximum permissible gross weight, measured in kilowatts per ton (kW/t). A higher ratio indicates better power performance, which enhances operational efficiency during emergency tasks.
3. Curb Weight
Curb weight refers to the total weight of the fire truck when it is fully equipped, with coolant and fuel filled to specified levels, but without any extinguishing agents or occupants (excluding the spare tire). It reflects the vehicle's weight in an unloaded, ready-to-operate condition.
4. Fully Loaded Gross Weight
This is the total weight of the fire truck when fully equipped, with coolant and fuel filled, extinguishing agents loaded, and all designated occupants (including the driver) on board (excluding the spare tire). This weight represents the vehicle in actual operation conditions.
5. Approach Angle
The approach angle is the maximum acute angle formed between the ground and a line touching the outer edge of the front tires when the vehicle is fully loaded and stationary. It indicates the vehicle's ability to approach obstacles without the front end scraping.
6. Departure Angle
The departure angle is the maximum acute angle between the ground and a line touching the outer edge of the rear tires when the vehicle is fully loaded and stationary. It measures the likelihood of the rear of the vehicle making contact with the ground when leaving an obstacle.
7. Minimum Ground Clearance
Minimum ground clearance is the vertical distance between the lowest point of the vehicle (excluding the wheels) and the ground when the fire truck is fully loaded and stationary. A greater clearance allows the vehicle to pass over obstacles such as rocks and stumps more easily.
8. Breakover Angle
The breakover angle is the smallest acute angle formed on the vehicle's side profile by lines drawn tangent to the front and rear tire contact points and intersecting at the lowest point of the vehicle's underbody. It reflects the vehicle’s ability to cross over crests or raised terrain without bottoming out.
9. Minimum Turning Diameter
The minimum turning diameter is the diameter of the circular path traced by the center of the outer front tire when the wheels are turned to the maximum angle. Since left and right turning angles may differ, there are separate measurements for left and right turning diameters. This parameter indicates the vehicle's maneuverability in confined spaces.
