Product Description Ventilation principle of drop hammer fan The main function of the hammer fan is to cool and exhaust, so do you understand its ventilation principle? The fan exhausts the air outward, which makes the indoor air pressure drop and the indoor air become thinner, forming a negative pressure area. The air flows into the room due to the compensation of the pressure difference. In the practical application of industrial plant, the fan is installed on one side of the plant, the air inlet is on the other side of the plant, and the air is convective from the air inlet to the fan. In this process, the doors and windows near th fan remain closed, forcing air into the workshop from the door and window on the air inlet side. The air in line and orderly flows into the workshop from the air inlet, flows through the workshop, and is discharged from the workshop by the fan. Detailed Photos Product Parameters Modle specification Diameter blades(mm) Blades rotational speed Motor rotational speed rpm Air flow (m³/h) (Pa) total pressure Noise decibels Import power(w) Rated voltage(v) Height(mm) Width(mm) Thickness(mm) JMD-800(29'') 710 660 1400 22000 60 ≤60 370 380 800 800 400 JMD-900(30'') 750 630 1400 28000 65 ≤65 550 380 900 900 400 JMD-1000(36'') 900 610 1400 30000 70 ≤70 750 380 1000 1000 400 JMD-1100(40'') 1000 600 1400 32500 70 ≤70 750 380 1100 1100 400 JMD-1220(44'') 1100 460 1400 38000 73 ≤70 1100 380 1220 1220 400 JMD-1380(50'') 1250 439 1400 44000 56 ≤75 1100 380 1380 1380 400 JMD-1530(56'') 1400 325 1400 55800 60 ≤70 1500 380 1530 1530 400 FAQ 1.Are you trading company or manufacturer ? We are manufacturer and produce by ourself. 2.When can i get the quotation? You will be able to obtain it within 24 hours once we get your inquiry. 3.How about your delivery time ? We will finish the order within 15 days for 40ft container,if more we need negotiate with you. 4.Do you provide samples? Is it free ? Yes, we could offer the free samples for evaluation but do not pay the cost of freight. 5.Can you accept OEM or ODM? Yes, of course.