Nearly 30 years of professional research and development experience in blowers, and drawing on the advanced experience of foreign axial blowers, the United Nations internal medicine research units, universities and colleges, through careful design, calculation and a large number of model and physical blower testing, development and gradual expansion and improvement, have DZ, T35, T40, DBF, LTF (JT-LZ), LFF, SFZ, SWF, HTF, SDF, and other 10 series of axial blowers of more than 250 specifications. The axial flow ventilator designed and produced by the company has distinctive characteristics such as high efficiency, low noise, stable performance curve, wide operating efficiency zone, compact structure, safe and reliable operation, simple adjustment of variable working conditions, easy installation and maintenance. Its overall performance is ahead of similar products in the same industry and is in the position of a domestic leader. The conveying medium is air and natural gases that are harmless to the human body. The axial-flow ventilators produced by the company have been widely used in HVAC systems and fire-fighting smoke exhaust systems such as industrial and mining enterprises, subways, tunnels, power plants, high-rise buildings, underground garages, etc. After operation assessment, users have given high praise.
Second, the installation of the blower
2． 1. Instructions before installation
To ensure the quality of installation and improve work efficiency, preparations need to be made before installation：
1． Be familiar with the design drawings, materials, instructions and other design documents of the installation object. Including: familiar with the installation pattern of the ventilator body, master the structural characteristics of the ventilator; familiar with the ventilation system pattern of the ventilator, familiar with the working condition and role of the ventilator in the system; familiar with the basic acceptance specifications of the ventilator and its construction conditions, according to the design pattern to check the specifications of the ventilator, the type, the direction of rotation of the impeller, the power requirements of the prime mover, the center distance of the anchor bolt hole, the aperture and orientation of the air inlet and outlet flange and the center distance, whether the center elevation of the shaft meets the design requirements.
2． Count the specifications and quantities of the accessories, accessories, and parts of the ventilator according to the packing list, and then conduct visual inspections, such as whether the shell is corroded, sunken and damaged, and whether the rotor is deformed or bruised.
3． The inspected problems, including design, equipment, construction and other issues, should be submitted to the relevant departments immediately for resolution, otherwise the installation work cannot be carried out.
4． The inspection list should be kept by a special person. The small parts should be nailed to the original box for safekeeping. The ventilators and motors should be equipped with rain sheds, and the bottom of the products should be provided with cushions to prevent the products from being placed in the open air or sinking in mud and water.
5． Note that the above work should be carried out jointly with the competent department responsible for equipment supply, and detailed records should be checked and checked.
2． 2. Installation instructions
1. Mechanical inspection: Before the installation of the blower, the blower impeller must be swung arbitrarily to see if it is deformed by transportation pressure or loose bolts, causing shell collision and uneven radial clearance, etc., otherwise it should be adjusted. At the same time, check the blower housing for garbage, debris, etc., otherwise it should be cleaned up.
2. When the blower shell is connected to the air duct, the positioning pin should be temporarily fixed first, and then all the bolts should be tightened by aligning the screw holes. When the diameter of the blower is ≥800mm or the blade tip speed is ≥80m/s, a shock absorber should be installed. When installing, pay attention to the level of the shock absorber, and tighten the foot bolts strung together between the blower and the shock absorber. When the air duct turns, it must be avoided to maintain a distance greater than 2 times the diameter of the blower from the installation position of the blower. At the same time, the weight of the pipe must not be added to the housing of the blower.
3. When the blower is installed, the grounding protection wire must be connected according to the motor installation method. Motors greater than 30kW should be equipped with current protectors, and motors less than 30kW should be equipped with fuses at the motor switch. The motor has protective wires in the junction box. After the wiring is completed, the cable inlet must be blocked to prevent dust and water vapor from entering the motor junction box. Fasten all wire connection bolts to prevent the contact thermal resistance from being too high and the heat of the wire from increasing.
4. Regardless of whether the horizontal or vertical blower is installed, attention should be paid to the firmness of the foundation, focusing on the bearing capacity of the blower's dynamic load. When horizontal hoisting, attention should be paid to the hanging force and the strength of the damping hook. When horizontal wall bracket installation, attention should be paid to the strength of the bracket. When roof installation, attention should be paid to the firmness of the base and whether there will be water leakage on rainy days.
5. When the blowers are installed in series, the positions of the two blowers should be kept at a distance of more than 5 times the diameter of the blowers; when installed in parallel, the consistency of the blower number and performance parameters must be guaranteed.
Third, the operation of the blower
After the blower is installed, the following inspections should be carried out carefully before starting the blower：
1. Whether the voltage is within the normal range (generally 380 volts, with a tolerance of ±6%), and whether the three-phase current is basically balanced.
2. Whether the gap between the blower impeller and the chassis meets the design requirements, and whether the manual rotating impeller is stuck and rubbed.
3. There are no debris in the blower housing or in the pipeline.
4. Whether the direction of rotation of the impeller is consistent with the direction of rotation of the blower.
5. Whether the actual speed of the motor is consistent with the speed of the blower.
6. Whether the grounding protection wire and current protector (fuse) of the motor are installed as required.
Commissioning and operation can only be carried out after the general inspection is qualified. When starting, check whether the allowable current of the motor is overloaded.
After starting, the vibration of the blower should be detected, and if severe vibration is found, the power should be turned off and stopped immediately for inspection.
Matching the blower with the system is extremely important. During the trial operation, it is necessary to pay attention to whether the blower is within the specified operating condition area, so as not to cause the current overload of the blower motor or the occurrence of blower surge due to the deviation between the actual system resistance and the design system resistance is too large. If the above situation occurs, it should be stopped immediately and appropriate measures should be taken to resolve it.
If everything is normal, stop after 10 to 30 minutes of starting operation and check whether the bolts on the impeller are loose. After everything is normal, it can be officially started and put into normal operation.
During the normal operation of the blower, the current of the motor is mainly monitored. Current is not only a sign of blower load, but also a forecast signal for some abnormal accidents. The second is to always check whether the motor bearing temperature and the vibration of the blower are normal and whether there are abnormal sounds of friction and collision.
During normal operation, if you encounter the following situations, you should stop immediately for inspection or repair：
1. The current suddenly rises and exceeds the specified value.
2. Strong vibration or rubbing sound occurs.
3. The temperature of the motor bearing has risen sharply.
blowers that enter stable operation should operate within the specified high-efficiency working conditions, otherwise, the power consumption of the blower will increase, the vibration will increase, and even the service life of the blower will be shortened.
Fourth, the maintenance and maintenance of the blower
In order to avoid man-made failures and accidents caused by improper maintenance, and to prevent natural failures in all aspects of blowers and motors, so as to give full play to the efficiency of the equipment and extend the service life of the equipment, the maintenance of the blowers must be strengthened.
Precautions for blower maintenance work：
1. It can only operate if the blower equipment is completely normal.
2. When the blower equipment starts after maintenance, it is necessary to pay attention to whether the blower components are normal.
3. Regularly check the fastening of the connecting bolts of the motor and the chassis, check the fastening of the bolts on the blower impeller, and check the fastening of the connecting bolts of the shock absorber.
4. Regularly check whether the blower is running within the working conditions.
5. Regularly remove impurities such as ash and dirt from the surface area of the leaves.
6. Replace the grease for the motor bearings regularly, generally once every three months, and the grease can also be replaced according to the actual situation.
Note: The quality of the grease is poor, which can easily cause the temperature rise of the motor bearing to be too high.
7. It should be stopped for overhaul and maintenance once a year. Note: After disassembling the blades, they should be marked so that they can be assembled in situ when reinstalled to avoid damaging the dynamic balance quality of the impeller and causing vibration.
8. When the blower needs to be reused after being disabled for a long time for more than one year, the motor should be checked for moisture, flooding, etc. If so, the motor should be sent to the motor production plant for drying, and the motor bearings should be cleaned and replaced with lubricating grease according to the relevant requirements of the motor factory.
9. In order to ensure personal safety, the maintenance and maintenance of the blower must be carried out during shutdown.
5. The cause of the failure and the troubleshooting method
5． 1. Common faults and causes of blower operation
blower vibration is too large
A. The blade accumulates ash, excessive dirt, or the blade is misplaced after maintenance, causing the impeller to be unbalanced.；
B. The connecting bolts of the blades are loose, causing the blades to collide with the chassis.；
C. The installation foundation of the blower is damaged, resulting in insufficient foundation stiffness；
D. Loose motor installation bolts；
E. The blower and the system pipeline are not installed well, causing resonance；
F. The motor bearing is damaged.
Motor bearing temperature rise
A. Motor overheating caused by abnormal vibration of the blower due to loose fixing bolts of the blower；
B. Motor grease is of poor quality, deteriorates, or is overfilled, contains dust, sticky sand, dirt and other impurities, and affects bearing lubrication caused by motor overheating；
C. The resistance of the blower is too large or the three-phase current is unbalanced, or the motor overheats caused by the voltage is too low.；
D. Improper selection of the blower, resulting in unreasonable matching of the performance parameters of the blower with the system, causing the motor to overheat due to power overload.；
E. The selection and arrangement of motor bearings are unreasonable, or the motor bearings are damaged.
blower debugging and running current is too large
A. The inlet and outlet air ducts are clogged when turning on；
B. The deviation between the system resistance and the design resistance is too large；
C. The density of the gas transported by the blower increases, resulting in an increase in pressure；
D. The input voltage of the motor is too low or the single-phase power failure of the power supply.
E. Affected by severe motor vibration.