I. Overview

SDF series tunnel ventilation fans are suitable for tunnel construction ventilation in highway, railway and hydropower projects, and other underground engineering construction ventilation. Main products include SDF _(A) type tunnel construction dedicated contra-rotating axial flow fan, SDF _(B) type tunnel worker dedicated contra-rotating axial flow fan, SDF _(C) type tunnel construction dedicated multi-speed contra-rotating axial flow fan, SDF _(D4) Energy-saving long construction tunnel construction four-stage contra-rotating axial flow fan, SDF _(E) New type tunnel dedicated axial flow fan, SDF _(P) New type tunnel construction dedicated variable frequency energy-saving ventilation fan, and hundreds of other specifications in five series.

II. Working Principle

The number of blades in the first and second stages is different. The two-stage impellers are very close to each other and rotate relatively. The first-stage impeller rotates clockwise, and the second-stage impeller rotates counterclockwise. After the first-stage impeller obtains energy, it directly enters the second-stage impeller for pressure increase before being discharged. The function of the second-stage impeller, in addition to increasing airflow energy, also has the function of the stationary guide vanes of other types of axial flow fans. While obtaining the guided straightening circumferential velocity component, it not only smooths the impact of the airflow and increases the energy of the airflow, but also reduces the noise.

III. Structural Features

1. Impeller: The impellers of the fans manufactured by our company adopt an adjustable moving blade design, which can be adjusted according to different ventilation needs. It also meets the ventilation needs of plateau environments. Material: Steel, and arc flame spraying treatment; its strength is 20 times that of ordinary materials, with advantages such as corrosion resistance and high strength.

2. Dynamic Balance Test: Our company has a ø2.0 dynamic balance test bench, and all fans are tested before leaving the factory to ensure product quality.

3. Fan Noise and Vibration: Silencers are installed at the inlet and outlet ends of the fan to meet the standard values stipulated in JB/T8690 "Noise Limits for Industrial Ventilation Fans". The A-weighted noise LSA ≤ 25dB(A) at the best efficiency operating point; vibration is lower than the vibration effective value (RMS) 4.6mm/s stipulated in JB/T8689 "Ventilation Fan Vibration Detection and Its Limit Values".

4. Housing and Other Component Materials: The housing adopts double-layer plate welding, with ultrafine glass fiber cotton lining in the middle to achieve good noise reduction effect. The fan is sturdy and durable, has a long lifespan, and has undergone strict surface treatment; the minimum design service life of the fan is not less than 15 years.

5. Fan Manufacturing Standards: The fan is strictly manufactured according to national standards and relevant industry standards.

6. The fan has the characteristics of compact structure, long air delivery distance, high efficiency, convenient maintenance, and convenient repair.

7. The fan's performance is strictly inspected before leaving the factory, and relevant certificates of conformity are included.

Special Note

I. Instructions for Use of Plateau Extra-Long Tunnel Ventilation Fans

The installation angle of the SDF series tunnel ventilation fans produced by our company is adjustable and can be used for construction ventilation in plateau environments. When using, simply adjust to the corresponding installation angle under the altitude conditions, with the characteristics of simple operation and convenient use.

When the fan is used in plateau areas, due to the low atmospheric pressure, the air density at the fan's usage site is lower than 1.2kg/m³, resulting in the actual pressure of the fan being lower than the value in the performance table. In this case, the calculation of the fan performance is as follows:

Flow rate Q = Qo (m³/min)

Pressure =

P _o ——Pressure in the performance table (Pa)

P _bo ——Standard atmospheric pressure 101235Pa

P _b ——The pressure at the fan's usage site, the relationship between atmospheric pressure and altitude is:

Where: H - Altitude, unit: km T - Temperature at the fan's usage site (°C)

II. When users select and use fans, the diameter of the matching air duct must be larger than the impeller diameter. When selecting air ducts, flexible air ducts are preferred, with a leakage rate ≤ 1%, to achieve the best effect. The fan outlet is equipped with a direct head that is easy to connect with the air duct (a variable diameter joint that meets the requirements can also be made according to user needs).

According to the construction situation, the manufacturer recommends using air ducts with the following corresponding diameters. (Note: It is forbidden to use steel ring negative pressure air ducts).

III. According to user needs, non-standard fan design can also be carried out, providing optimal aerodynamic and structural design solutions to provide users with economical and reliable fans.

SDF _(A) Tunnel Construction Dedicated Contra-rotating Axial Flow Fan

I. Features

The SDF(A) type fan features high wind pressure, low noise, and energy saving; it is suitable for small cross-section operations such as subways, water diversion projects, and oil pipeline projects, with particularly significant energy-saving effects.

II. Model and Meaning

The fan model and meaning are as follows: SDF(A) type tunnel construction dedicated contra-rotating axial flow fan

III. Technical Performance Parameter Table

IV. Structural Diagram

V. Dimensions

Note: If the fan dimensions change, the dimensions provided at the time of order confirmation will prevail.

The company's main business is the design, research and development, and manufacturing of various ventilators and their supporting products for mines, non-coal mines, and rail transit. Products involve 38 series of fan products, more than 3,000 specifications, including FB(D) series, FBC(D)Z series, FKZ series, rail transit SDS series, tunnel SDF series, etc.; supporting products include shaft, inclined shaft self-resetting explosion-proof doors, louver-type automatic regulating air doors, side-opening (vertical) automatic regulating air doors, butterfly valves, silencers, main ventilator online detection and fault diagnosis systems, non-stop fan reverse systems and intelligent oil injection systems, which can fully meet the ventilation needs of mines and are sold to various domestic fields and international markets such as Russia and Canada.

In recent years, the company has successively won the honorary titles of "Yuncheng Enterprise Technology Center", "Yuncheng Excellent Enterprise", "Yuncheng Intellectual Property Demonstration Enterprise", and "Innovative Small and Medium-sized Enterprise". The company has passed the "ISO9001 Quality Management System Certification", "ISO14001 Environmental Management System Certification", "ISO45001 Occupational Health and Safety Management System Certification", and its products have passed the "China National Compulsory Product Certification". It has also obtained a number of patents. With advanced process equipment, strong technical strength, excellent product quality, and a perfect service system, it has won unanimous recognition and praise from users. In particular, the green, environmentally friendly, and low-noise fans that have been focused on the market in recent years have achieved rapid development, becoming a well-known enterprise in the fan industry with leading technology.