To balance engine power, cooling requirements, and explosion-proof scenarios, the key is to establish a three-step matching logic: "Scenario Adaptation - Parameter Calculation - Graded Selection." This avoids both performance redundancy and security vulnerabilities. Specifically, follow these steps:
1. Step 1: Identify the specificities of the explosion-proof scenario and identify the basic safety threshold.
First, determine the explosion-proof level and core limitations based on the operating environment. This is the prerequisite for avoiding "inadequate explosion-proof" performance. Two key pieces of information must be identified:

Explosive Substance Type: Distinguish between flammable gases (such as methane and propane) and combustible dusts (such as coal dust and flour). Select the appropriate explosion-proof structure. For gas environments, select "Explosion-Proof (Ex d)"; for dust environments, select "Dust Explosion-Proof (Ex tD)" to avoid protection failure due to incorrect usage.
Environmental Hazard Level: Zones are divided according to the GB 50058 standard (e.g., gas environments: Zone 0, Zone 1, and Zone 2; dust environments: Zone 20, Zone 21, and Zone 22). For high-risk areas where explosive materials are frequently present, such as Zone 1 and Zone 21, a higher explosion-proof rating (e.g., Ex dⅡCT6) should be selected. For areas where explosive materials are occasionally present, such as Zone 2 and Zone 22, a lower rating (e.g., Ex dⅡBT4) can be selected to avoid blindly selecting a higher rating and resulting in costly waste.
2. Step 2: Accurately Calculate Cooling Requirements Based on Engine Power
Insufficient cooling can lead to engine overheating, while excessive cooling increases fan load. Two key parameters are needed to establish a matching relationship between power and cooling:
Calculating Cooling Power Requirement: Based on the engine power formula, the following is derived: Cooling Requirement (Q) ≈ Engine Power (P) × Heat Loss Coefficient (typically 0.25-0.35). For example, a 100kW engine requires approximately 25-35kW of heat dissipation. Based on these parameters, select the fan's "heat dissipation capacity parameters" (e.g., air volume ≥ 5000m³/h, air pressure ≥ 300Pa) to ensure the fan can meet the engine's heat dissipation requirements at full load, avoiding downtime due to insufficient heat dissipation.

Matching the fan drive method: For small equipment with engine power ≤50kW, a "belt-driven fan" (low cost and simple structure) is an option. For large equipment with power >50kW (such as heavy trucks and generator sets), a "motor-driven fan" (with variable frequency drive and adjustable speed) is recommended. This fan delivers full power dissipation under high load, reduces speed to save energy under low load, and prevents friction sparks caused by belt slippage, achieving a balanced balance of heat dissipation efficiency and explosion-proof safety. 3. Step 3: Balancing explosion protection and cost using a "tiered selection" principle
Based on the "explosion protection threshold" and "heat dissipation parameters" determined in the first two steps, select components according to three tiers to avoid over- or under-performance:
Core component: Fan blade material grading: For high-risk scenarios (Zones 1/21 + high-power engines), choose carbon fiber composite (temperature resistance 180°C+, explosion protection rating Ex dⅡCT6); for medium-risk scenarios (Zones 2/22 + low- and medium-power engines), choose modified aluminum alloy (temperature resistance 120°C+, explosion protection rating Ex dⅡBT4); for low-risk scenarios (only occasional explosive materials), choose copper alloy (lower cost than composite materials and meets basic explosion protection requirements). Avoid using the most expensive material for all scenarios. Auxiliary Structures: Add protective features as needed: Redundant devices such as overspeed protectors and temperature sensors are only required for fans in high-risk areas such as Zone 1 and Zone 21. For Zone 2 and Zone 22, some auxiliary features can be omitted, retaining only the basic explosion-proof structure to reduce unnecessary component costs.
Verification: Conduct a "power-heat dissipation-explosion-proof" linkage test. After selecting a model, test it in a simulated environment. Run the engine at full power for one hour to monitor whether the fan's heat dissipation can keep the engine temperature within the normal range (e.g., ≤95°C for a diesel engine). Simultaneously, use a combustible gas detector to detect sparks and leaks around the fan to ensure both safety and performance meet standards, avoiding mismatches caused by theoretical calculations.
Would you like me to compile a matching table for engine power, explosion-proof scenarios, and fan selection? This table clearly identifies the fan materials, explosion-proof ratings, and heat dissipation parameters for different power ranges and hazardous areas, allowing for quick selection.