9-12风机的用途及特点
9-12型高压离心通风机，一般用于锻冶炉及高压强制通风，并可广泛用于输送物料、输送空气及无腐蚀性、不自燃、不含粘性物质之气体。介质温度一般不超过250℃（最高不超过300℃），介质中所含的尘土及硬质细颗粒不大于150mg/m3。本系列风机除具有以上特点外，还具有效率高、噪声低、流量调节范围大、高效区宽广、性能曲线平坦等优点。风机"三化"程度高，通用性好，适用范围广。
风机的型式
1、 风机制成单吸入，常用机号有№3、3.15、4、4.5、5、5.6、6.3、7.1、8、9、10、11.2、12、12.5、14、16、18、20等，共20多个机号。
2、 风机可制成右旋转或左旋转两种型式，从传动组部正视风机，如叶轮顺时针旋转称为顺时针旋转风机即右旋风机，以“右”表示，逆时针旋转，称为逆时针旋转风机即左旋风机，以“左”表示。
3、 风机的出口位置以机壳的出风口角度表示，“顺”“逆”均可制成0°、45°、90°、135°、180°、225°、270°共7种角度。
4、 风机的传动方式有A、B、C、D四种：
A一表示风机轴盘通过键槽安装在电机轴伸上，即电机直插；
B一表示悬臂支承装置，皮带传动，皮带轮在两轴承中间；
C一表示悬臂支承装置，皮带传动，但是皮带轮在轴承外侧；
D一表示悬臂支承装置，用联轴器联接驱动。
风机的结构
№3～7.1风机主要由机壳、叶轮、进风口、支架等部件组成；№7.1～以上型号风机主要由机壳、叶轮、进风口、传动组等部件组成。
机壳：由普通钢板焊接成蜗形壳整体。
叶轮：风机叶片为20片前向弯曲叶片，均匀相间地焊接于四圆弧型轮盖与平板型轮盘之间，组成的流道带有无叶扩压器，叶轮扩压器外缘最高圆周速度不超过140m/s，叶轮经静、动平衡校正和超速运转实验，运转平稳可靠。
进风口：做成收敛式流线型的整体结构，用螺栓固定在前盖板上。
传动组：由主轴、轴承箱、联轴器（皮带轮）等部件组成，主轴由优质钢制成，轴承箱为整体结构，采用滚动轴承，滚动轴承用轴承润滑脂润滑。
风机的性能与选择
风机的性能：风机的性能以风机的流量、全压、主轴转速，轴功率等参数表示。选择曲线与性能表中所给出的性能。送风机性能：t=20℃、大气压力Pa=101325Pa 、气体密度ρ＝1.2Kg/m³空气介质计算。（其他设计均按使用参数进行相似换算）
选择曲线与性能表中性能均指调节叶片为全开0℃时的性能。订货时以性能表为准。风机性能试验全压值的偏差不超过设计全压值的5%。
如风机使用条件与上述不符时，性能应按相关公式进行换算。
流量过多或不足时的处理。在使用时，常常发生流量过多或不足的现象，产生这种现象的原因很多，如果是在使用过程中发生流量时大时小的现象，主要是由于管网中的阻力时大时小。如果是在使用过程中，经过较长时间逐渐减少，主要是由于管网堵塞。
在风机新安装后，进行正式运转时就发生流量过大或不足现象的原因主要有下列几点：
1、管网阻力实际值与计算值相差过大。
由一般管网特性方程式：P=Kq²，式中K—阻力系数。
如实际值K小于计算值K时，则流量增大，若实际值K大于计算值K，则流量减小。
2、选择时未考虑风机本身全压值编差δP的影响，当风机实际全压为正偏差时，则流量增大；为负偏差时，则流量减小。
在风机新安装后开始正式运转时，或在使用过程中发生流量过大或过小时，可采用下列方法之一消除之；
利用增减风机的转速调节流量。
利用调换新的压力较高或低的风机以增减流量。
改变管网阻力系数K以改变流量。
此时可设法改变管网使阻力系数减小以增加流量，也可增加风机转速和调换压力较高的风机，但转速不得大于性能表中最大转速。
风机的安装与使用
安装前：应对风机各部件进行全面检查，机件是否完整，叶轮与机壳的旋转方向是否一致，各部联接是否紧密，叶轮、主轴、轴承等主要机件有无损伤。传动组是否灵活等。
安装时：注意检查机壳，机壳内不应有掉入或遗留的工具或杂物，在一些结合面上为了防止生锈，减少拆卸困难，应涂上一层润滑脂或机械油，风机与地基结合面和风机与进出风管道联接面应调整使之自然吻合，不得强行联接，更不许将管道重量加在风机各部件上，并注意保证风机的水平位置。
安装要求：
1、 按图纸所示的位置与尺寸安装，为确保高效率，特别要保证进风口与叶轮的轴向和径向间隙尺寸（出厂前已调整好）。
2、 安装后试拨传动组，检查是否有过紧或与固定部分磨擦现象。
3、 全部安装完毕，总检合格后，才能进行风机的试运转。
4、 为防止电机过载烧毁，在风机启动时，必须在无载荷（将进风阀门关闭，出风阀门稍开）的情况下进行，如情况良好，逐步开启阀门，直到达到额定工况为止。在运转过程中应严格控制电流，不得超标。
风机的操作
风机启动前，应进行下列准备工作。
(1) 将进口阀门关闭，出口阀门稍开。
(2) “点车”查看风机及其系统有无异声、异振，如有应排除之，如无，点车时间逐渐拉长，直至正常运行。
(3) 风机启动达到正常转速时，应在运转过程中经常检查轴承温度是否正常，当轴承温度没有特殊要求时，轴承温升不得超过环境温度40℃，轴承部分的均方根振动速度值不得大于6.3m/S。如发现风机有剧烈的振动、撞击、轴承温升迅速上升等到现象时，则必须紧急停车。
风机的维护
（1） 风机及其系统不许带病运行。
（2） 风机应由专人保管，专人使用。
（3） 定期清除风机内部积灰，污垢等杂质，并防止生锈。
（4） 风机的维护必须在停机断电时进行。
（5） 风机维修、试车时禁止无关人员及行动不便者在场围观。
（6） 风机试车时，在风机进出口方向十米之内不许站人。
（7） 风机维修后应清点工具及其它用品，以防遗留在风机及管道内部。
（8） 除每次检修后应更换润滑剂外，正常情况下根据实际情况更换润滑剂。
风机的主要故障及原因
1、 风机剧烈振动
（1） 风机轴与电机轴不同心。
（2） 机壳与叶轮或进风口与叶轮摩擦。
（3） 基础的刚度不够或不牢固。
（4） 叶轮铆钉松动或叶轮变形。
（5） 叶轮轴盘孔与轴配合松动。
（6） 机壳、轴承座与支架，轴承座与轴承盖等联接螺栓松动。
（7） 风机口、出风管道安装不良，产生共振。
（8） 叶片有积灰、污垢、叶片磨损、叶片变形、轴弯曲等原因使转子不平衡。
2、 轴承温升过高
（1） 轴承箱剧烈振动；
（2） 润滑剂质量不良、变质或含有灰尘、砂粒、污垢等杂质或填充量不足；
（3） 轴承箱盖、座联接螺栓之紧力过大或过小；
（4） 轴与滚动轴承装歪斜、前后两轴承不同心；
（5） 滚动轴承损坏或轴弯曲；
3、 电机电流过大或电机温升过高
（1） 开车时进、出气管道闸门未关；
（2） 电机输入电压低或电源单相断电；
（3） 受轴承箱剧烈振动的影响；
（4） 主轴转速超过额定值。
订货需知
订货时请注明风机型号、机号、流量、全压、输送介质、使用温度、出口角度及旋转方向等。
如用户之需要与本说明书提供性能不符时，请与本厂设计部门联系特殊型号的风机。
Purpose and characteristics of the fan
Model 9-12 centrifugal fan is generally used for forging furnace and high pressure forced ventilation, widely used for materiel delivery and suitable to delivery air and gas of non-corrosion, non self-burn and free of viscous material. The temperature of the delivered medium shall normally not exceed 250℃(not exceed 300℃ maximum), the dust contained in the medium and hard-fine particle shall not be bigger than 150mg/m3. This series of fans in addition to the above characteristics,but also has high efficiency, low noise, large flow adjustment range, flat performance curve and so on. Fan three high degree of versatility, good versatility, wide range of application.
Type of fan
1. The fan is made as a single suction and its driving is A type. There are more than 20 types of fan numbers which are 3、3.15、4、4.5、5、5.6、6.3、7.1、8、9、10、11.2、12、12.5、14、16、18、and 20.
2. The fan can be made of 2 types of rotation i.e, right and left. Viewing from one end of the motor, it is called as clock-wise fan if the impeller rotates clock-wise, shown as “right”, On the contrary, it is called as counter-clock-wise fan if the impeller rotates counter-clock-wise, shown as “left”.
3. The outlet position of the fan can be expressed from the outlet angle of the casing. It can be made 7 kinds of angles which are 0°, 45°,90°, 135°,180°,225°, 270°，from both “Right” and “left”.
4. There are 4 driving modes: A,B, C, D:
A—Shaft disc of fan is installed on motor shaft by keyway, i.e. motor directly connecting;
B—Cantilever bearing unit, belt driving, pulley is in the middle of two bearings;
C—Cantilever bearing unit, belt driving, but the pulley is outside the bearing;
D—Cantilever bearing unit, coupling directly driving.
Structure of the fan
№3-7.1 fan mainly consists of impeller, casing and inlet. №7.1- above fan mainly consists of impeller, casing inlet and Driving unit.
Casing: to be welded into a volute with normal steel plate.
Impeller: The fan has 20 forward-curved blades. The maximum circumference speed of impeller diffuser shall not exceed 140m/s. The impeller, after being shaped, shall be balanced statically and dynamicaly and thus it guarantees a smooth operation.
Inlet: to be integrated into a convergent streamlined structure and bolted on the front cover.
Driving unit—it consists of shaft, bearing box, rolling bearing, belt pulley or coupling.
See the attached drawing for installation and overall dimension.
Performance and selection of the fan
Performance of the fan:The performance of the fan is expressed by the parameters of fan flow, full pressure, spindle speed, shaft power and so on. Performance curve and the performance of the performance given in the table. Blower performance: When ordering the performance table shall prevail. Fan performance test total pressure value of 5% of the total pressure deviation is less than design value.
Such as fan using condition does not accord with the above, the performance shall be carried out according to the related formula conversion.
When excessive or insufficient flow of processing. When use, often occur the phenomenon of excessive or insufficient flow, produce a lot of reasons for this phenomenon, if it is in use process flow occurs when small phenomenon, is mainly due to the resistance of pipe network. If it is in use process, after a long time to reduce gradually, mainly due to network congestion.
After the fan is a new installation, a formal operation occurs when the flow phenomenon of excessive or insufficient reason mainly has the following points:
1、The actual value and calculating value difference is too large in the resistance of pipelines.
By the general network characteristic equation: P = Kq, type of K - drag coefficient.
If the actual value K is less than the calculated value K, increases the flow, if the actual value is greater than the calculated value K K, the flow decreases.
2、When the choice is not the fan itself fully considering the influence of the pressure deviation of P, when fan actual total pressure for positive deviation, then the flow; Negative deviation, the flow rate decreases.
Began formal operation after fan is a new installation, or in use process flow is too big or too hours, one of the following methods can be used to eliminate the;
Make use of the fan speed adjusting flow increase or decrease.
Using the new high or low pressure switch to increase or decrease in flow rate of fan.
Change the pipeline resistance coefficient K to change traffic.
At this time to try to change the network reduce drag coefficient to increase traffic, also can increase the fan rotation speed and changing the high pressure fan, but speed shall not be greater than the maximum speed performance table.
Installation and use of fan
9-19 type fan only gives the non-dimensional performance table of №10 sample fan (see table1). The dimensional performance of the fan can be calculated with given non-dimensional performance table.
The dimensional parameter formula is calculated with non-dimensional
parameter.
If it is in non-standard state when operating, the performance of non-standard standard state must be converted to the performance of standard state. And then select fan according to the converted performance. The converting formula is as follows:
Installation and operation of the fan
Before installation: Check all components of the fan to see weather any thing is missed; weather the impeller rotates in the same direction as the casing; weather all components are connected tightly and weather the impeller rotates freely.
During installation: Pay attention to check the casing and any tools or goods should not be dropped and remained inside the casing. The connecting face between the support of the fan and the foundation or between pads and foundation should be tight. Adjusting should be made to joint the fan with foundation surface and to connect the fan with suction, discharge duct naturally. Forced assembling, especially, applying weight of pipes on any components of the fan isimpermissible. Also, attention shall be paid to the horizontality of the fan.
Requirement of installation:
(1) Install the fan according to the position and sizes shown on the drawing. To
insure high efficiency, radial and axial clearances between inlet and impeller must be guaranteed.
(2) After installation, turn, with a little force, the driving rotor to see if it is over
tight or touched with stationary components.
(3) Commission Can only be carried out after the unit is through the final
inspection. In order to prevent the motor being burnt out due to overloading, the fan
can only be started up and tested without loading. If the case is ok, increase the load
step by step until the rated operating condition is reached. Control the current strictly
during operation to prevent it exceeding the rated value.
Operation of the fan:
(1) Before starting-up, the following preparations shall be made:
a) Close the valve of suction pipe and open a little the valve on discharge pipe.
b) Check the rotating and non –rotating parts to prevent colliding and friction.
(2) After the fan is started-up and the normal speed is reached, check the bearing temperature is normal or not during the operation. If there is no special requirement for bearing temperature, the temperature rise of the bearing shall not exceed 40℃ of surrounding temperature. The value of even root vibration speed of the bearing shall comply with the following rules: rigid support(support is fixed on the foundation) Vrms≤4.6mm/s; flexible support(be set onfoundation or floor through absorber) Vrms≤7.1mm/s. In case that severe vibration, colliding, quick rise of bearing temperature and other abnormal phenomena are found, stop the fan immediately.
Maintenance of the fan
1) Cautions in fan maintenance:
① The fan can only be put into operation in normal condition.
② When the fan is started-up after inspection, attention should be paid to see
weather each component is ok or not.
③ Check periodically the dust and contamination inside the fan to prevent rust.
④ Maintenance can be carried out during shut down of fan to assure operators
safety
2) Cautions in normal operation of the fan
① During the star-up, shut-down or operation of the fan, if some abnormal thing
happens, inspections shall be carried out immediately; if it is small failure, the reason shall be checked out and eliminated, if it is a big failure, the fan shall be stopped and inspection and maintenance shall be made immediately.
② Replace lubricant grease of motor bearing according to the real condition.
The main failure and reason of the fan
1) severe vibration of the fan
① friction between casing (or suction unit)and impeller.
② Foundation is not rigid enough or firm enough.
③ loosing of rivets in impeller or deformation of impeller.
④ Loose match of shaft with impeller disc
⑤ Loose of connecting bolts between casing and support, and between motor and
support.
⑥ The installation of inlet and outlet ducts is improper which causes the casing
deformation and resonance.
⑦ Rotor unbalance caused by dust, contamination on blades, wear of blades,
deformation of impeller and bending of shaft.
2) High rise of bearing temperature
①severe vibration
② lubricant is poor in quality, deteriorated, mixed with dust, sand, contamination
and etc, or insufficient in quantity.
③Wornout of rolling bearing
3) Overcurrent and high temperature rise in motor.
① The valves on inlet and outlet pipes are not closed completely when starting-up.
② Input voltage is low or a single phase of power supply is cot out.
③ Influence caused by severe vibration
④ The speed of main shaft is bigger than the rated value.
Supply scope of fan unit
One fan, one driving motor and 4 sets of foundation bolts
Purchase information
1）when purchasing, indicate the size, speed, flow, pressure, discharge angle and rotating direction of the fan, and the model, power, and speed of the motor.
2）Also, indication shall be made clearly when ordering, if you need inlet filter, silencer, inlet and outlet soft connection, vibration absorbing platform and vibration absorber.
