How to choose the right motor for a Roots blower?

The three-phase asynchronous motor consists of two basic parts: the stator and the rotor. The stator is the fixed part of the motor, used to generate a rotating magnetic field, mainly composed of the stator core, stator winding, and base components. The rotor is the rotating part of the motor, made up of the rotor core, rotor winding, and rotor shaft, which functions to obtain torque under the action of the rotating magnetic field. The rotor is divided into squirrel-cage rotors and wound rotors based on its structure. The winding of the squirrel-cage rotor is cast together with bare conductors placed in the slots of the rotor core, along with annular end rings at both ends and fan blades. Small and medium-sized rotors generally use cast aluminum, while for motors with a capacity greater than 100KW, due to the difficulty in ensuring the quality of cast aluminum, copper bars are often inserted into the slots of the rotor core, welded at both ends with end rings, resembling a squirrel cage. The winding of the wound rotor is similar to that of the stator winding, using insulated conductors embedded in the rotor core slots, forming a three-phase symmetrical winding connected in a star configuration, with the three output terminals connected to three slip rings on the rotor shaft, and then connected to the external circuit through brushes, to improve starting performance or adjust the motor's speed. Squirrel-cage motors have a simple structure, low price, and relatively simple control of motor operation, so they are widely used. In contrast, wound motors have a complex structure, higher price, and relatively more complex control of motor operation, making their application relatively less common. However, wound motors are generally used in heavy load applications due to their larger starting and operating torque.

2022-05-21

The fan manufacturer will help you understand the difference between high-efficiency motors and ordinary motors.

Roots blowers, as major consumers of electricity, have their performance and energy consumption directly affected by the quality of the motor. While most people may know the difference between variable frequency motors and ordinary motors, they generally do not understand the differences between ordinary motors and high-efficiency motors. Later, Mingfeng Machinery will help you understand the detailed situation. In China, motor energy consumption accounts for more than 50% of total energy consumption. Since its establishment, China has developed five generations of low-voltage motor products, from the earliest J, J02 series to the later YX3, YE3 series, with efficiency levels continuously improving. However, the penetration rate of high-efficiency motors has always been low, leading to significant waste. Therefore, starting in 2009, the country began to gradually phase out high-energy-consuming motor products, completing the elimination of the Y3 series and various low-efficiency motors named by enterprises before 2003 (inclusive) by 2015, and stopping production. So what is a high-efficiency motor, and how does it differ from an ordinary motor? In China, motor energy efficiency is divided into three levels. A high-efficiency motor refers to a motor whose energy efficiency meets the national mandatory standard GB18613-2006 "Energy Efficiency Limit Values and Energy Efficiency Grades for Small and Medium-sized Three-phase Asynchronous Motors" at the second-level energy efficiency index. The difference between high-efficiency motors and ordinary motors lies first in the differences in efficiency and energy consumption. High-efficiency motors reduce losses by adopting reasonable stator and rotor slot numbers, fan parameters, and sine winding measures, achieving higher efficiency than ordinary motors. High-efficiency motors are on average 3% more efficient than ordinary motors, while super high-efficiency motors are nearly 5% more efficient. In terms of energy consumption, high-efficiency motors consume about 20% less energy on average than ordinary motors, while super high-efficiency motors consume more than 30% less. Secondly, there is a cost difference. High-efficiency motors, by using high-quality materials and optimized designs, have a higher cost than ordinary motors. High-efficiency motors cost 25%-30% more than ordinary motors, while super high-efficiency motors can be 40%-60% more expensive. However, in general, the investment in high-efficiency motors can be recovered within two years, and they can save electricity for enterprises throughout their entire lifecycle. Moreover, combined with the national subsidy policy for high-efficiency energy-saving motors (Notice on the Implementation Rules for the Promotion of High-Efficiency Motors under the Energy-Saving Products Benefit Project), the cost difference is minimal. In addition, high-efficiency motors operate at lower temperatures, have longer lifespans, and lower maintenance costs; and due to their smaller slip rates, their speeds can also be higher than those of ordinary motors.

2022-05-21

What are the precautions for textile machinery Roots blowers?

What should be noted about the fans specifically for textile machinery? The editor from Mingfeng Machinery will guide you through it. The Roots blower dedicated to textile machinery must keep the impeller clean and regularly brush off the accumulated dust and rust with a wire brush. As the running time increases, this accumulation cannot adhere evenly to the impeller, leading to an imbalance and causing rotor vibration. The maintenance of the Roots blower casing and intake box, besides regularly checking for severe wear inside the casing and intake box and removing significant dust accumulation, does not require any other special maintenance. Regularly check if all fastening bolts are tightened. For the maintenance of the main shaft and coupling, the main shaft should be kept clean, and the shoulder should be scraped of dirt annually. Poor manufacturing quality of the fan or severe wear of the fan can lead to a decrease in fan speed. To eliminate the operation in an unstable zone: adjust the pipeline resistance curve, reduce resistance, and change the working point of the fan. Repair the fan. Increase the fan speed. Adjust the working area of the fan. The above are the precautions regarding the Roots blower for textile machinery explained by the editor. See you next time.

2022-04-25

Will the parameters be affected after the Roots blower is connected in series?

When multiple Roots blowers work together, series connection mainly increases pressure, while parallel connection mainly increases flow. However, the performance of Roots blowers when working together is not simply additive. Generally, when in parallel, Roots blowers will use equipment of the same model and performance parameters. If equipment of different models and different speeds are connected in parallel, the situation is similar to the above, but at this time, the equipment with lower performance may output very little air volume or even fail to deliver air when the total flow decreases. Therefore, connecting blowers of different models and parameters in parallel is more complex and is generally less common. The series connection of Roots blower equipment refers to adding another blower device at the intake of the main blower. This increases the air density at the intake of the main blower, increasing the air mass per unit volume, which raises the compression ratio, hence series connection can increase pressure. If blowers with different performance parameters are connected in series, the situation is even more complex, influenced by the pipeline characteristic curve as well as the blower equipment parameters and their positions. Pressure will only be increased under specific conditions; otherwise, it may have the opposite effect.

2022-04-24

How to choose a suitable adapter for a Roots blower?

There are many types of production machinery, with varying performance and process requirements, and their torque characteristics are also different. Therefore, before applying a frequency converter, it is essential to first clarify the nature of the load carried by the motor, which is the load characteristics, and then select the frequency converter. When choosing a frequency converter, the actual motor current value should be used as the basis for selection, while the motor's rated power can only serve as a reference. If the frequency converter is to operate with long cables, measures should be taken to suppress the impact of the long cable's ground coupling capacitance to avoid insufficient output from the frequency converter. Therefore, the frequency converter should be selected one level higher or an output reactor should be installed at the output end of the frequency converter. When the frequency converter is used to control several motors in parallel, it is crucial to consider that the total length of the cable from the frequency converter to the motor is within the allowable range of the frequency converter. If it exceeds the specified value, the frequency converter should be selected one or two levels higher. For loads with significant torque fluctuations, such as compressors and vibrators, and for peak load situations like oil pumps, it is important to understand the operating conditions at power frequency and select a frequency converter with a rated output current greater than its maximum current. When the frequency converter drives a submersible pump motor, since the rated current of the submersible pump motor is larger than that of a typical motor, the rated current of the frequency converter must be greater than the rated current of the submersible pump motor. Regarding the issue of selecting matching adapters, the editor of Mingfeng Machinery has organized the above content for everyone. If there are any questions, feel free to discuss them in the next issue.

2022-04-24

Under what circumstances does a Roots blower need to replace the lubricating gear oil?

Typically, when using a Roots blower, the lubricating oil inside the machine serves functions such as lubrication, reducing friction, protection, and cleaning. Therefore, in general, various blower equipment will set corresponding replacement cycles based on actual usage conditions. So, under what circumstances do we need to replace it? Below, the editor from Mingfeng Machinery will help everyone understand. After normal use, gear oil is generally replaced every 1 to 2 months, and the decision to replace can be made by observing the deepening color of the oil. Depending on the changes in oil performance, the cycle may become shorter or longer; replacing too early will increase usage costs, while replacing too late will affect the performance of the Roots blower. Ultimately, it depends on the actual quality of the lubricating oil to see if it has oxidized or deteriorated. When replacing gear oil, avoid mixing new and old gear oils; old oil should be removed before adding new oil. Failures during the warranty period of the Roots blower are often due to not replacing the lubricating oil in a timely manner, so during routine inspections, the condition of the lubricating oil should be checked.

2022-04-22

How to choose between a centrifugal blower and an axial fan?

Both online and offline fan retailers offer many fans for us to choose from, but how do we find the ideal fan that meets our needs? Which type of fan is more suitable for you? Below, Mingfeng Machinery provides a detailed introduction. The common principle of axial fans is to allow air to pass through the fan by a shaft that rotates parallel to the blades, which is why they are named axial fans. The characteristic of axial fans is that they have a high flow rate, but the air pressure they generate is relatively low. Axial fans are very suitable for applications that require a large amount of air circulation. Compared to centrifugal blowers, they require less power. The operating method of centrifugal blowers is different from that of axial fans. Centrifugal blowers do not draw air in parallel to the axis; instead, they move air radially from the center. Compared to axial fans, centrifugal blowers generate higher pressure airflow.

2022-04-18

How do different industries choose Roots blowers?

How to choose the right motor for a Roots blower? The editor from Mingfeng Machinery will guide you on how to select the appropriate blower. Three-lobe Roots blowers are widely used in the environmental protection industry (wastewater treatment, desulfurization and dust removal), aquaculture, grain processing, steel smelting, pneumatic conveying, electric power, petrochemicals, cement, mineral selection, textiles, papermaking, printing, electronics, and other sectors of the national economy. Due to their good sealing properties, they can also be used to transport flammable, explosive, and corrosive gases such as carbon monoxide, biogas, coal gas, hydrogen, acetylene, and carbon dioxide. Rotary blowers are used for aeration in water treatment; wastewater stirring and aeration in hospitals, hotels, ships, and laboratories; vacuum paper feeding in the printing industry; stirring and aeration in electroplating tanks and industrial wastewater; gas supply for plastic welding and packaging; spraying for burners, glass industry, and other fields. Asynchronous electric motors consist of two basic parts: the stator and the rotor. The stator is the fixed part of the motor, used to generate a rotating magnetic field, mainly composed of the stator core, stator winding, and base. The rotor is the rotating part of the motor, composed of the rotor core, rotor winding, and shaft, and its function is to obtain torque under the action of the rotating magnetic field.

2022-04-15

How to adjust the Roots blower for long-term shutdown

Due to production and other reasons, when the Roots blower needs to be shut down for a long time, it is recommended to strictly follow the handling methods, especially in seasons or regions where the temperature is below 0°C or humidity is high, to properly protect the Roots blower equipment. Wrap electrical devices such as controllers and distribution boxes with plastic or oil paper to prevent moisture, dust, and other intrusions. Place a desiccant in front of the air filter, which should be replaced approximately every six months, and seal all openings to prevent moisture and dust from entering. If there are any faults or issues before shutdown, they should be resolved first to facilitate future use. Regardless of the type of blower, it cannot be neglected for a long time, especially high-pressure blowers; even during the downtime, it is necessary to maintain them properly, otherwise, the functionality of the equipment will be greatly affected.

2022-04-15

In which industries are Roots blowers applicable? What are the benefits?

The three-lobe Roots blower is widely used in the chemical industry and is utilized under different working conditions, such as transporting chemical raw materials, conveying reaction gases, aeration stirring, wastewater treatment, ventilation and exhaust, gas pressurization, and pulse dust removal. These are important indicators of the pneumatic conveying performance of Roots blowers. In the wastewater treatment industry, the three-lobe Roots blower can provide a quantitative amount of oxygen based on different water depths and treatment capacities, promoting the oxidation and decomposition by microorganisms. The operational management efficiency of the blower can directly influence the effectiveness of domestic wastewater treatment. In biological methods of wastewater treatment, it is essential to develop a sufficient supply of oxygen to promote the growth of aerobic microorganisms, which can effectively facilitate metabolic processes, breaking down suspended solids and organic compounds such as nitrogen and phosphorus in the wastewater. There are significant differences in aquaculture, with industrial aquaculture primarily using three-lobe Roots blowers. For enterprises with larger farming areas, there are thermal power plants that require desulfurization of flue gas. The sulfur dioxide content in the flue gas will be greatly reduced after chemical reactions, meeting emission standards. In this chemical reaction process, sulfur dioxide turns into crystals and crystallizes out, which requires the oxidation of oxygen. Therefore, Roots blowers will be used to provide sufficient oxygen to ensure the efficient operation of the chemical reaction. Desulfurization oxidation by Roots blowers: flue gas desulfurization is carried out by chemical methods, and the sulfur dioxide content in the flue gas will be significantly reduced after chemical reactions to meet emission regulations.

2022-04-12