Overview SDS series jet fan specifications from 630mm ~ 1600mm, sub-way operation and reversible axial fans (two-way) running axial fans into two categories, the maximum thrust has 3500N, for any load and operating conditions can be selected for high efficiency, low noise fan. SDS series jet fan use of advanced technology to achieve good quality assurance, fan casing use of US imports of machine tools for spinning flanging, the inner wall of the impeller section through the processing, both to ensure concentricity and strength of the cabinet and ensure blade radial clearance, the appearance of hot-dip galvanized or other equivalent coating process, appearance and corrosion, excellent performance, fan blades, hub using Toshiba automatic CNC boring and milling machining center into a die-casting mold cavity, respectively, high pressure casting and low pressure casting machine aluminum high (low) die casting, by road tunnels, railway tunnels, hydroelectric dam project and other users of the actual use of proven, the fans of the performance indicators and corrosion resistance, reliability, economy and other technology quality requirements and is fully able to adapt to all kinds of economic indicators tunnel, subway use. Product usage instructions in the subway, tunnel, railway tunnel construction and other infrastructure projects, which air quality standards, safety factor by a forced ventilation fans to meet the requirements. For the purposes of the ventilation system, to maintain long-term good air quality, or harmful, as described below. Tunnel ventilation system design and product selection based on traffic tunnel in principle be divided into three categories: the subway, tunnel, railway tunnel. Running under normal operating and emergency safety, reliability is a prerequisite to ensure coordination between the various systems installed and fully functioning environmental control system. A mechanical systems: ventilation, fire ', sewerage B power system: power supply, transmission and distribution, emergency power lighting system C: through lighting, local lighting, fluorescent indicator D communication system: telephone, radio, computer terminals E transport: light , signals, signs, monitoring F control system: traffic situation and equipment condition monitoring equipment operation and tunnel ventilation systems can have the following three basic ways or hybrid approach can be taken. 1 Longitudinal Ventilation System: This is the most basic ventilation. The new wind tunnel airflow from the inlet end to the outlet end, longitudinally along the tunnel without having to install the ventilation pipe. The ventilation is generally used in jet fan can be reversed. The fan mounted on the top or side of the tunnel, two directions can be fully ventilated in order to achieve two-way ventilation or smoke control; if the tunnel is longer, you must add a central delivery, ventilation shafts, shaft with the atmosphere to form a hybrid ventilation mode. 2 full-transverse ventilation system: Set send along the tunnel direction, flues, fresh air from the air pavilion centralized collection and exhaust are excluded from wind towers, typically the air flow passage provided in the pavement below the upper part of the exhaust path is provided in the driveway, sending flue duct and has sent at regular spacing, air vents, under accident conditions along the tunnel cross-section in a timely manner the exhaust, thereby extracting smoke. 3 semi-transverse ventilation system: The system can be divided into air-type semi-transverse ventilation and exhaust-type semi-transverse ventilation, the general type of semi-transverse ventilation exhaust, fresh air enters from the hole, similar to full-transverse ventilation exhaust system . Factors that should be considered Tunnel Ventilation System: A project investment B power capacity C above factors operating costs assurance measures for comprehensive economic safety factor D E F air quality after the establishment of an emergency program to optimize 5, tunnel ventilation system fan number, machine No selection factors: A CO, NOx and smoke density B traffic (vehicle density, speed) C wind loads (tunnel L * W * H) D emissions (vehicle age, the number of) emergency measures in case of fire E 6, Axial Tunnel Ventilation System to calculate a theoretical calculation based on the thrust tunnel ventilation system inlet and outlet pressure loss? inferior equipment tunnel surface friction coefficient and friction coefficient of the vehicle (in the most disadvantaged conditions calculated vehicle motion or piston wind effects) the most disadvantaged conditions outside the cave wind speed on the impact of the entrance? tunneling topography, location (slope, elevation) of the desired thrust in case of fire (temperature, pressure, time) 2 tunnel buck (Pa) theory is converted to the desired jet fan thrust (N) jet fan thrust of momentum change fan inlet and outlet, both the fan thrust N = C * Mass Flow * airflow velocity (N) Where: N = fan static thrust (LSO) N value learning correction coefficient C = mass flow = air density * volume flow relative velocity jet fans used in the tunnel and the tunnel airflow between the friction coefficient and the tunnel are arranged in parallel with the impact of the group, so that the effective thrust jet fan is: N = N * (1- V / V) C * C where: N = fan effective thrust (N) V = wind speed in the tunnel (m / s) V = jet velocity (m / s) C = C = coefficient of friction of the tunnel with the group arranged in parallel flow losses (such as loss of lag between the fan unit Fan diameter 100 times, so that the jet velocity along the flow direction does not affect the operating conditions can not be considered). 7, tunnel ventilation system applications Fan structural characteristics of sub-way tunnel fan jet fan (SDS) and two-way jet fans [SDS (R)] two kinds of ventilation fans in the form of the body, muffler, mounting foot: CNC automatic welding steel plate and mechanisms for molding, the appearance of the surface coating, so as to ensure the fan strength and corrosion fan impeller: To meet the tunnel ventilation needs, SDS series fan may change the number of leaves, and changing the fan blade angle muffler: muffler length is usually a fan diameter times, when the noise requirements of high, fans also can take twice the diameter, muffler and fan body with bolts. Matching motor: SDS series jet fan matching motor is totally enclosed squirrel cage motor has a flange mounting plate, electrical insulation class H, corrosion rating to IP55, motor lead cable can be connected to the turbine casing body junction boxes, motors with lubricating grease nipple, the external metal hose connected to the blower nozzle body grease cabinet. Fans reversible switching time: in an emergency, jet fan reverse switching time is extremely important, SDS (R) type fan with electronic and mechanical switching method two, you can reverse the fan switch to the rated speed in 30 seconds. SDS series jet fan thrust test detection test: A test device measured thrust. High-temperature fire test: Test the Ministry of Public Security Tianjin Fire test center. Noise: Fan Importers mounted muffler and muffler are not installed for testing (atmospheric wind speed approaches zero) in the open field, fans SPL test for a 45 ° angle along the fan axis measured at 10m from the fan. Fan efficiency: Fan operating efficiency was determined by the thrust (N) and motor input power (KW) is defined. The test detected by the company to build on Engineering Technology Center (Experimental Research) strictly in accordance with national and industry standards were, and by the provincial and national authorities test for detection of the supervisory authority.