This article's table of contents introduction:
This is a specific model designation for a heavy-duty industrial fan used in underground coal mining ventilation. Here is a breakdown of what the model number FBCDZ-6-No13 means, along with the key features implied by the description.
Model Breakdown
F = Fan
B = Explosion-Proof (防爆)
C = (Typically) Counter-Rotating or "Forced" depending on the specific Chinese standard, but in this context (Exhaust + Counter-Rotating) it means Vertical installation (or "Shaft" type) for mine use. More accurately, in the standard MT/T 754-2005, 'C' stands for a vertical (shaft) installation configuration.
D = Electric Motor Direct Drive (the impellers are mounted directly on the motor shafts, no belts or long shafts).
Z = This is context-specific. In many Chinese fan naming conventions, this can denote a specific design feature like a diffuser, silencer, or a particular blade profile (e.g., 'Z' for 直板/Straight blade or 轴流式/Axial flow). In the FBCDZ series, it generally refers to the fan being part of a specific standardized series with a diffuser cone.
6 = Pole Number of the Motor (The motor runs at 6 poles, nominal speed ~980-990 RPM for a 50Hz power grid).
No13 = Impeller Diameter (The fan impeller is 13 decimeters in diameter, which is 3 meters).
Full Description: FBCDZ-6-No13
Primary Function: This is a main mine ventilation fan designed for exhaust (suction) service. It is placed at the top of a mine shaft or at a surface opening to draw stale, contaminated air (methane, dust, etc.) out of the underground workings.
Key Features & Technology
Counter-Rotating Axial Flow:
This fan has two impellers (rotors) that rotate in opposite directions.
There are no stationary guide vanes between the impellers.
Air enters through the 1st rotor, gets accelerated, and then passes directly into the 2nd rotor (spinning the opposite way). The 2nd rotor acts as a stator/rotor combination, straightening the airflow and recovering rotational energy. This principle provides very high efficiency (up to 85%+) and high pressure generation for a single axial fan stage.
Explosion-Proof (B) :
The fan casing and motor enclosures are designed to contain any internal methane gas explosion, preventing it from igniting the surrounding atmosphere.
The impellers are made of brass or aluminum alloy (non-sparking) to prevent frictional sparks against the steel casing.
Direct Drive (D) :
The two impellers are directly mounted on the shafts of two separate, specially designed explosion-proof motors housed within the fan cylinder.
Advantage: No belts, pulleys, or bearings to maintain in the airstream. High reliability and no power loss from mechanical transmission.
Reversible Ventilation:
A critical feature for mining. Because it is counter-rotating, the fan can achieve reverse airflow simply by swapping the electrical phases of one or both motors. This changes the rotation direction of the impellers, effectively reversing the airflow path.
Important: In reverse mode, the efficiency and pressure are lower than in forward mode, but it is sufficient for emergency anti-reversal operations (preventing gas from back-flowing into the mine). Typically, reverse airflow can reach 60-70% of the forward volume flow rate.
Technical Specifications (Approximate for this model)
| Parameter | Value / Range |
|---|---|
| Fan Model | FBCDZ-6-No13 |
| Type | Explosion-proof, Counter-rotating, Axial Flow |
| Impeller Diameter | 3 m (No13) |
| Airflow Volume (Q) | Typically 25 - 65 m³/s (90,000 - 230,000 m³/h) * |
| Static Pressure (P) | Typically 1500 - 3500 Pa * |
| Motor Speed | ~980 RPM (6-pole motor, 50Hz) |
| Motor Power (per motor) | Typically 2 x (30 kW to 75 kW) * |
| Motor Voltage | 380V / 660V / 1140V (Mining standard) |
| Efficiency (η) | ≥ 80% (Static efficiency) |
Note: Actual performance depends on the specific blade angle setting (adjustable in most models).
Application & Installation
Location: Installed on the surface at the exhaust air shaft head.
Configuration: Often installed in a vertical orientation (shaft outlet) or in a horizontal bypass duct system with isolating doors.
Backup: Typically installed in a pair (A & B fans) with isolating dampers. One operates while the other is on standby.
Regulation: Speed can be controlled via Variable Frequency Drives (VFDs) for energy savings, or blades can be adjusted on the impellers (if designed for pitch adjustment).
Summary
The FBCDZ-6-No13 is a robust, high-efficiency, explosion-proof axial fan specifically built for the demanding task of primary mine ventilation. Its counter-rotating direct-drive design offers high pressure, simple reversal (critical for safety), and minimal maintenance compared to old-style centrifugal fans or belt-driven axial fans. It is a standard choice for medium to large-sized coal mine ventilation systems.
