1、 1 Profile In order to provide you with a comfortable and quiet living and working environment, reduce the pollution of noise to the environment and improve peoples health, Hydromechanics Education and Research Institute of Tsinghua University developed 6-32, 6-45 and 6-41 series products of boiler
2、forced draft fan and induced draft fan together with our company. The noise limit values have reached the requirements of 1984 JJE No. 16 File issued by Beijing Environmental Protection Bureau in 1984 and 1986 on the noise limit of boiler forced draft fans. In 1993, we won the approval certificate f
3、or fan production issued by Beijing Environmental Protection Bureau. After tryout by the users in recent years, the after-sale feedback and monitored performances like flow rate, total pressure, efficiency and noise all meet the environmental and design requirements. With satisfactory effect, the pr
4、oducts are favored by the users. Advanced optimized pneumatics design methods are used for the fans, which have been detailed in the magazine Fluid Engineering, 11th Issue, 1988. Since 1985, we have developed a full set of quality assurance system gradually. The chairman of the board is mastering th
5、e quality work himself. The quality control system centering director, section chief and inspector has been established in the workshops and section offices, which has controlled the product quality at a high level and is improving it steadily. In 1987, we got the production license issued by State
6、Machinery Committee, and won Level 3 certificate of approval on measuring in the same year. During production, we carry out international, national and industrial standards on fans and internal control standards strictly to control the quality of products. In the inspection and assessment on auxilia
7、ry machines for boilers performed by China Industrial Boiler Inspection Center and Shanghai Industrial Boiler Research Institute in 1988, our six models of G/Y6-41 forced draft fans and induced draft fans, including 2t/h, 4t/h and 6t/h, were all awarded title of high-quality product. In 1988, we won
8、 the Second Prize of Beijing Science Progress, and in 1989 our products were awarded title of Beijing High-quality Product. In 1990, we won the Certificate of National Technology Achievement. In 1991, our products were listed in the 13th group of energy-saving products of mechanical industry, and at
9、 the end of the same year, the 2 Y6-41NQ 7.1C boiler induced draft fan was awarded High-quality Product of Year 1991 by the Ministry of Machine-building and Electronics Industry. On July 28th, 1993, the G/Y6-41 series was listed as a product under supervision by Boiler Pressure Vessel Inspection and
10、 Research Center of the Ministry of Labor of PRC. In May, 2000, the G/Y6-41 series passed the examination of State Mechanical Industry Bureau and was re-recognized as a practical project of energy-saving M survive with quality and develop with variety! Beijing Xishan Shengtong Fan Co., Ltd. (predece
11、ssor: Beijing Xishan Fan Factory) Tel: 62591627-8698 62591557 62593224-8698 Fax: 010-62593223 Post Code: 100089 Address: No.50, Xingkou Road, Haidian District, Beijing Route: Bus 347 from the Zoo to Xipingzhuang 3 I. Usage of fan Low-noise 6-32, 6-41 and 5-56 series boiler forced and induced draft f
12、ans are applicable to coal burning boilers. They can be equipped for 0.2t/h-90t/h boilers to work as the forced and induced draft system. The relevant machine numbers of fan for the different kinds of boilers are shown in the following table: Boiler output (t/h) Model No. and machine No. of forced d
13、raft fans Model No. and machine No. of induced draft fans Below 0.5 G6-41-11 N0.2.5A Y5-43-11 N0.2.8C Y6-41-11 N0.3.3C 0.5 G6-41-11 N0.2.5A G5-43-11 N0.2.8A Y6-41-11 N0.3.55C Y6-32-11 N0.3.7C Y6-41-11 N0.4C 1 G5-56-11 N0.3.3A G6-41-11 N0.3.3A Y6-32-11 N0.5C Y6-41-11 N0.4.5C 2 G6-45-11 N0.5.4A G6-41-
14、11 N0.5.4A Y6-32-11 N0.6C Y6-41-11 N0.5.4C 4 G6-45-11 N0.6，3A G6-41-11 N0.6.4A Y6-45-11 N0.7.5C Y6-41-11 N0.7.1C 6 G6-45-11 N0.7.1A G6-41-11 N0.7.1A Y6-45-11 N0.8C Y6-41-11 N0.10C Y6-41-11 N0.9C 10 G6-41-11 N0.8.5A G6-45-11 N0.8A Y6-41-11 N0.10.8D Y6-41-11 N0.11.2D Y5-56-11 N0.9.5D 20 G6-62-11 N0.9.
15、4D G5-56-11 N0.9A Y6-41-11 N0.12.2D Y5-56-11 N0.11.2D Y5-56-11 N0.11.5D Y5-56-1l N0.12D 30 G5-56-11 N0.10.2D Y5-56-11 N0.12.5D 35 G6-62-11 N0.12.4D Y5-56-11 N0.16D Y5-56-11 N0.14.2D 40 G6-62-11 N0.12.7D Y5-56-11 N0.16.5D Y5-56-11 N0.17D Y6-62-11 N0.12.7D 65 G5-56-11 N0.14.2D Y5-56-11 N0.18.5D 80/90
16、G5-56-11 N0.18.2D Y5-56-11 N0.20D 4 II. Type of fan The forced draft fans can be made in two types: right-handed rotation and left-handed rotation. Facing the fan from the drive line, if the fan impeller rotates clockwise, it is called right-handed rotation, short for “R“; and if the fan impeller ro
17、tates counter-clockwise, it is called left-handed rotation, shall for “L“. (See Fig. 1) The fans are made in single indraft type. The position of the outlet of fan is indicated with the angle of air outlet. “R and L“ can be both made in 0, 90, 180and 270. As shown in Fig.1, other angles like 45, 135
18、 and 225 can also be made as required. Boiler forced draft fans are designed for A-type or D-type transmission, and induced draft fans are designed for C-type or D-type transmission. Fig.1 Rotating direction and outlet position of fans III. Structure of fan A fan mainly consists of impeller, casing,
19、 air inlet, support and motor. 1. Impeller: tip-back circular arc line blades are welded between arc cone wheel cap and flat disc, after finish machining, with strict static and dynamic balance calibration, 5 they can run smoothly and reliably, with good pneumatic performance, low noise and high eff
20、iciency. 2. Casing: snail-shape shell welded with plain steel plate, independent of the support or welded to the support, steady and reliable. 3. Air inlet: convergent streamline structure, fixed at the entrance side of the fan with bolts. 4. Drive line: consists of main shaft, integral bearing box,
21、 antifriction bearing, belt pulley or coupling, lubricated with #46 engine oil, with good sealability, smooth performance and long life. IV. Selection and use of fan 1. When you decide to use our boiler forced and induced draft fans, please make your choice by referring to the fan performance parame
22、ters shown below according to the pressure and flow required for the working conditions. The working conditions shall be as close to the original design parameters as possible. 2. The parameters listed in the tables are the parameters under the following working conditions: For forced draft fan: med
23、ium temperature 20; atmospheric pressure 101325 pa; gas density 1.2kg/m3, relative humidity 50%. For induced draft fan: medium temperature 200; atmospheric pressure 101325 pa; gas density 0.745kg/m3. When your operating conditions are different from the above-mentioned conditions, they shall be conv
24、erted with the following formulas: Total pressure:P0*(B/101325)*(273+t0)/(273+t1) (pa) Flow: Q1=Q0 (m3/h) Effective power: N1=N0*(B/101325)*(273+t0)/(273+t1) (KW) In which: P0, Q0 and N0 are total pressure, flow and effective power in the performance table respectively. P1, Q1 and N1 are total press
25、ure, flow and effective power under actual working 6 conditions respectively. B is the atmospheric pressure on site (pa) T1 is the medium temperature when the fan is working ( ) T0 is the medium temperature stated in the performance table () Determination of fan power: Required power: N（P1Q1/1000136
26、00）K（P1Q1/3.61061）K (KW) In which: Q1 is the flow of the fan (m3/h) P1 is the total pressure (pa) K is the reserve coefficient of motor; usually K1.3- 1.5 1, mechanical transmission efficiency:10.95 (belt driven) 10.98 (Coupling driven) , internal efficiency of fan 3. The conversion relation between
27、 flow, total pressure, rotation rate and power under the same intake conditions as those in the performance table: n0/n1=Q0/Q1=P0/P1=3N0/N1 In which: n0 is the rated revolution per minute in the performance table From the above relation and the formulas in article 2, we shall notice that: Before the
28、 capacity of electric motor is increased, the induced draft fan (design working temperature) shall not be run under cold condition; and the rotation speed of the fan shall not be increased at will. Otherwise, the motor will be overloaded and even burnt out. 4. Use of non-dimensional graph See Fig.2
29、for the non-dimensional performance curve of 6-41 series fans, for your reference to convert to dimensional parameters. The formula is as follows: P=P222 ; Q=（Q2d22/4）2；N=N2（d22/4）23/1000 In which: P, the total pressure wanted (pa) P2, total pressure coefficient of the fan , gas density (kg/m3) 2, s
30、peed of impeller outer circle (m/s) Q, the flow wanted (m3/s) 7 Q2, Flow coefficient of fan D2, impeller outer diameter (m) N, the effective power wanted (KW) N2, power coefficient of fan Fig. 2 Non-dimensional Performance Curve of 6-41 Series Fan 5. Adjustment of flow When you are using the new fan
31、s, you may run into over flow or deficient flow from time to time. There are many causes, mainly as follows: (1) The difference between the actual value and the calculated value of pipe network resistance is too large. General pipe network characteristic equation: PKQ2 In which: P is the pipe networ
32、k resistance value K is the coefficient of resistance 8 Q is the gas flow. After the pipe network is determined, it must be mapped to a coefficient of resistance K. If the K value selected in design is different from the actual K value, there will be flow difference, as shown in Fig. 3b. When Ks K,
33、the flow is smaller; when Ks K, the flow is larger. Graph of relation between pipe network resistance and fan performance (2) When selecting the fan, if the effect of deviation of the total pressure of fan itself is not considered, while the performance on the label of fan is that under normal condi
34、tions, there will be deviation of total pressure when the working conditions of different regions are different. When the actual total pressure of fan is at plus deviation, the flow is increased; when it is at minus deviation, the flow is decreased. As shown in Fig. 3a. Advice: re-calculate or repla
35、ce the fan or modify the pipe network When the fan has run for a while, it may run into flow deficiency, with some basic causes as follows: 1) The speed of fan is reduced and need to be set to rated speed. 2) The pipe network resistance changes, possibly because there is leakage or blockage, and the
36、 pipe network shall be adjusted. 3) The age of fan is old with serious abrasion and the impellers have lost working ability. It needs to be repaired or changed. 9 V. Installation and commissioning of fan 1. Before installation: Carry out complete inspection on all parts of the fan: whether the compo
37、nets are intact; whether the rotation direction indicated on the label and the casing are the same as that of the impellers; Whether all the parts are joined tightly; whether there is damage on the critical parts like the main shaft of impellers; and whether the drive line is flexible. If any proble
38、ms are found, it shall be repaired and adjusted. 2. During installation: Check and clean out the foreign matters dropping into or left in the casing. Check the interface between the fan and the foundation. The inlet and outlet pipes shall be fitted naturally, no connecting by force, let alone adding
39、 the weight of pipes on the parts of the fan. In order to reduce noise, flexible connection shall be use to reduce vibration. During installation, the level position of the drive parts of the fan shall be guaranteed. 3. Installation requirement: (1) The fan shall be installed according to the positi
40、on and size shown in the drawing. In order to ensure the performance of the fan, the axial and radial gap size of the air inlet and impeller shall be guaranteed in particular. (2) When installing D-type driving fans, the level position of the main shaft of fan and the coaxiality of motor shaft shall
41、 be guaranteed. The installation of couplings shall meet the specifications for installation of elastic coupling. When installing C-type driving fans, the surface of V-belt pulley of main shaft and the surface of V-belt pulley of motor shall be parallel. The gulf shall not be out of position, and sa
42、feguards shall be mounted after putting on rubber belt. (self-provided by users) (3) After installation, check for the rotation: whether it is too tight, whether there is friction or collision. Adjust it in time. (4) For the drive line with cooling water jacket, the the cooling water pipe system sha
43、ll be connected, and the joint surface shall be inspected for leakage by passing water. (5) Use oil dipstick or oil immersion lens to test the oil level inside the bearing box. The oil level shall be between the internal ring and external ring underneath the bearing. 10 4. Operation and maintenance
44、of fan: (1) Before starting, the regulating valve shall be closed, and check the electromechanical parts, the electric circuits, the cooling and the lubrication. Only after all these have been verified can the motor be started up. (2) After the motor speed becomes normal, open the regulating valve t
45、o practical status point gradually. (3) Control the electric current strictly under rated value during operation, and check the bearing temperature frequently. If the temperature rises up to 40 higher than the ambient temperature or there are abnormal phenomena like excessive vibration (the R.M.S. v
46、ibration velocity of the bearing part shall meet the requirement of JB/T 8689-1998) or impact sound, it must be shut down immediately to find the causes. (4) The newly-installed or repaired fans must be verified through trial run before they can be put into use. The induced draft fans shall get thro
47、ugh short-time commissioning at ordinary temperature, and the electric current and temperature rise of the motor shall be monitored. Once any abnormality comes up, shut down immediately. (5) If the fan is not equipped with regulating valve and adopts soft startup or transducer instead: When starting
48、 the fan: raise the low speed n (0.5nr) up to the rated speed gradually. When the induced draft fan is started at ordinary temperature (cold condition) in trial run, the electric current of the motor shall be monitored and not allowed to exceed the rated current. When the fan is running, use transdu
49、cer to adjust the rotation speed of the fan to required working conditions if a transducer is adopted. VI. Maintenance of fan: In order to avoid personal injury and natural failure due to improper maintenance, improve the efficiency of equipment and extend the service life of equipment, the fans must be maintained well: 1. Cautions for fan maintenance: (1) Only when the fan is totally in good conditions can it be run. (2) If the fan is started after maintenance, pay attention to the conditions of every
