centrifugal pump rated temperature

1. The basic structure of a centrifugal pump is composed of six parts: the impeller, the pump body, the pump shaft, the bearings, the sealing ring, and the stuffing box. 1. The impeller is the core part of the centrifugal pump. It has a higher speed and greater power, and the blades on the impeller play a major role. The impeller must pass a static balance test before assembly. The inner and outer surfaces of the impeller must be smooth to reduce friction losses in the water flow. 2. The pump body is also called the pump casing, which is the main body of the water pump. It plays a supporting and fixing role and is connected to the bracket where the bearing is installed. 3. The function of the pump shaft is to connect the motor with the coupling and transmit the torque of the motor to the impeller, so it is the main component for transmitting mechanical energy. 4. The bearing is a component that is sleeved on the pump shaft to support the pump shaft. There are two types of rolling bearings and sliding bearings. Rolling bearings use butter as lubricant. The oil should be refueled appropriately, generally 2/3 to 3/4. Too much will cause heat, too little will cause noise and heat! Sliding bearings use transparent oil as lubricant, add oil to the oil level line. Too much oil will seep out along the pump shaft and drift, too little bearings will overheat and burn out, causing accidents! During the operation of the water pump, the temperature of the bearings reaches a maximum of 85 degrees and generally runs around 60 degrees. If it is high, find the cause (whether there are impurities, whether the oil is black, whether water has entered) and deal with it in time! 5. The sealing ring is also called the leakage reduction ring. If the gap between the impeller inlet and the pump casing is too large, the water in the high-pressure area in the pump will flow to the low-pressure area through this gap, affecting the water output of the pump and reducing the efficiency! If the gap is too small, it will cause friction between the impeller and the pump casing and cause wear. In order to increase the backflow resistance, reduce internal leakage, and extend the service life of the impeller and pump casing, a sealing ring is installed at the joint between the inner edge of the pump casing and the outer edge of the impeller. The sealing gap is preferably maintained between 0.25 and 1.10mm. 6. The stuffing box is mainly composed of stuffing, water seal ring, stuffing barrel, stuffing gland and water seal tube. The main function of the stuffing box is to close the gap between the pump casing and the pump shaft, prevent the water in the pump from flowing outside and prevent outside air from entering the pump. Always maintain a vacuum inside the water pump! When the friction between the pump shaft and the packing generates heat, the water seal tube must be used to trap the water into the water seal ring to cool the packing! Keep the water pump running properly. Therefore, special attention should be paid to the inspection of the stuffing box during the inspection of the water pump operation! The packing must be replaced after about 600 hours of operation. 2. The flow-passing parts of the centrifugal pump The flow-passing parts of the centrifugal pump are: There are three parts: suction chamber, impeller and pressure chamber. The impeller chamber is the core of the pump and the core of the flow components. The pump works on the liquid through the impeller, increasing its energy. Impellers are divided into three categories according to the direction of liquid outflow.: (1) Radial flow impeller (centrifugal impeller) liquid flows out of the impeller in a direction perpendicular to the axis. (2) Inclined flow impeller (mixed flow impeller) The liquid flows out of the impeller along the inclined direction of the axis. (3) The direction of liquid flow in the axial flow impeller is parallel to the axis. Impellers are divided into two categories according to the way of suction: (1) Single suction impeller (that is, the impeller sucks liquid from one side). (2) Double-suction impeller (that is, the impeller sucks liquid from both sides). Impellers are divided into three categories according to cover plate form: (1) Closed impeller. (2) Open impeller. (3) Semi-open impeller. Among them, closed impellers are widely used, and the aforementioned single-suction impellers and double-suction impellers all belong to this form. 3. Working principle of centrifugal pump The working principle of centrifugal pump is: The centrifugal pump can send water out because of the centrifugal force. Before the water pump works, the pump body and water inlet pipe must be filled with water to create a vacuum state. When the impeller rotates rapidly, the blades cause the water to rotate quickly. The rotating water flies away from the impeller under the action of centrifugal force. After the water in the pump is thrown out, a vacuum area is formed in the center of the impeller. The water in Suwon is forced into the water inlet pipe through the pipe network under the action of atmospheric pressure (or water pressure). In this way, continuous water pumping can be achieved by endless circulation. It is worth mentioning here that: Before starting the centrifugal pump, the pump casing must be filled with water before starting. Otherwise, it will cause the pump body to heat up, vibrate, reduce the water output, cause damage to the water pump (referred to as "cavitation") and cause equipment accidents! There are many types of centrifugal pumps, and the common classification methods are as follows: 1. According to the impeller suction method: Single suction centrifugal pump Double suction centrifugal pump. 2According to the number of impellers: Single stage centrifugal pump multi-stage centrifugal pump. 3 According to impeller structure: Open impeller centrifugal pump Semi-open impeller centrifugal pump Closed impeller centrifugal pump. 4 According to working pressure: Low pressure centrifugal pump, medium pressure centrifugal pump, high pressure centrifugal pump, side vertical centrifugal pump. 4. The following introduces several important performance curves of centrifugal pumps. There is a certain relationship between the performance parameters of the water pump, such as flow Q, head H, axis power N, speed n efficiency η. The relationship between the magnitude changes between them is represented by a curve, which is called the performance curve of the water pump. The mutual changing relationship and mutual constraints between the performance parameters of water pumps: First of all, the top speed of the water pump is a prerequisite. There are three main curves in the water pump performance curve:: Flow-head curve, flow-power curve, flow-efficiency curve. A. Flow-lift characteristic curve It is the basic performance curve of a centrifugal pump. Centrifugal pumps with a specific speed less than 80 have the characteristics of rising and falling (both convex in the middle and downward curves on both sides), which is called a hump performance curve. Centrifugal pumps with specific speeds between 80 and 150 have a flat performance curve. Centrifugal pumps with specific rotational speeds above 150 have steep performance curves. Generally speaking, when the flow rate is small, the head is high, and as the flow rate increases, the head gradually decreases. B. Flow-power curve The shaft power increases with the flow rate. When the flow rate Q=0, the corresponding shaft power is not equal to zero, but is a certain value (about 60% of normal operation). This power is mainly consumed in mechanical losses. At this time, the water pump is filled with water. If it runs for a long time, the temperature inside the pump will continue to rise. The pump casing and bearings will heat up. In severe cases, the pump body may be thermally deformed. This is called "stuffy head". At this time, the lift is at its maximum value. When the water outlet valve gradually opens, the flow rate will gradually increase, and the shaft power will also slowly increase. C. The flow-efficiency curve is shaped like a mountain. When the flow rate is zero, the efficiency is also equal to zero. As the flow rate increases, the efficiency gradually increases, but after it increases to a certain value, the efficiency decreases. The efficiency has a maximum value. Near the highest efficiency point, the efficiency is relatively high. This area is called a high-efficiency area. 5. Reasonable configuration, safe operation, and high-quality water supply. After understanding the structure, working principle, and characteristic curve of the centrifugal pump from the above four aspects, how to reasonably configure the power of the motor water pump is the key to ensuring the safe operation of the water pump, high-quality water supply, and reducing production costs. Properly configure the water pump power to maximize the safe operation of the best working area of ​​the water pump. The actual water supply situation of our factory has fully demonstrated the importance, reliability, and economy of reasonable equipment configuration. 1. The importance of reasonable configuration of pump equipment. The main task of the water plant is to ensure the city's people's production and domestic water supply. The South Plant originally had a maximum daily water supply of 900,000 tons, and the water inflow and output could meet the regional pressure. However, in the past ten years, with the relocation of municipalities and the migration of large water users, the water supply has been decreasing. As the quality of people's lives has improved, the demand for water quality has become higher and higher. The factory water has reached 0.3NTU. How to ensure high-quality water supply, the company has taken a series of measures: (a) Adjust the reasonable configuration of mechanical and pump equipment and implement the best combination of man and machine. (b) Increase scientific and technological innovation and invest a lot of money to transform the original backward water purification equipment. (C) Invest funds, transform old equipment and old pipe networks, improve hydraulic conditions, install static mixers, etc. (D) Install forty instruments and use a modern monitoring system to monitor and control water quality throughout the entire process to ensure high-quality water. These measures fully illustrate the importance of reasonable configuration of pump equipment and water purification equipment. 2. Reliability of safe operation of pump equipment. In order to ensure the safe operation of pump equipment, enterprises have more standardized management of pump equipment, including annual overhaul, monthly secondary maintenance, and daily first-level maintenance system. These ISO9002 quality management are various measures to ensure the safe operation of pump equipment. In order to ensure the reliability of safe operation, the technical quality of operators must be trained and improved, and the implementation of safe operating procedures must be strictly implemented. The implementation of these safe operating systems is a guarantee to ensure the reliability of the operation of pump equipment. 3. The economy of safe operation of pump equipment. When it comes to economics, it means the cost of water production by an enterprise, including electricity, alum, chlorine, and ammonia. It is necessary to use the safest operation method, the best dispatch mode, and the lowest water production cost to control the economic activities of the enterprise and improve economic efficiency. In this regard, the enterprise has accumulated certain experience. like: The safest operation method is that Shanghai's urban water supply pipe network is interconnected. There is a company's central dispatching room to control the regional water supply pressure. If it is too high, it will easily cause pipe bursts, which will cause great harm to the people and the public. * * Causes property damage, low water pressure, affects water use for some users, and creates a bad image of the company. Therefore, the pressure in the daytime area is maintained at about 30-35 kPa, and the pressure in the nighttime area is kept below 30 kPa. According to the requirements of the pipe network pressure, the high-lift pump is turned on during the day and the high-lift and low-lift combination is turned on at night, which effectively controls the factory water pressure and ensures the water supply of the regional pipe network and hotel high-rise buildings. Using these optimal pump combinations not only saves power consumption, but also reasonably controls the pressure. These methods ensure the economical and safe operation of the pump equipment. With the continuous development of science and technology, the modernization of water pumps has also continued to improve, reducing a lot of manual management operations. Nowadays, most of them adopt the automatic operation mode of computer monitoring, which puts forward higher requirements on the quality of the operators themselves. Because an abnormal condition of a water pump will affect the entire water supply system network, causing serious consequences. After several years of practical work and theoretical study, * , apply the knowledge learned to practical work, reasonably arrange the distribution and dispatch of water volume, use the characteristics of each water pump to use the least power to achieve the maximum water output of the water pump, and achieve the best operating condition. And achieve safe, high-quality, low-consumption water supply! I've never heard of the rated temperature you mentioned, so I don't really understand it!

I have never heard of the rated temperature of a pump. The bearing temperature is generally used. The bearing temperature generally cannot exceed 75 degrees. In pipeline design, the design temperature of the pipeline cannot exceed the maximum operating temperature of the pump, otherwise it will cause damage to the pump.

I have also mostly heard about bearing temperature

The pump should have two temperatures. One is the maximum operating temperature of the motor bearing and the other is the design temperature of the pump head. It is related to the material. The material should not exceed this temperature.

The so-called rated temperature is the temperature specified when determining the rated flow rate and rated pressure. I would like to give you some advice. When someone asks about the temperature, you answer a lot of pump classifications, principles, etc. Obviously the article is not correct! You can also get charm rewards, which is incredible! ! ! ! ! !

I have never heard of the rated temperature of the pump, the operating temperature of the medium, and the bearing temperature when selecting the pump.

When selecting a pump, the flow rate, head, medium, working conditions, i.e. medium temperature, etc. are required. The bearing temperature should be determined according to the working conditions. Ordinary IS pumps are lower than 80 degrees, while ISR pumps can reach more than 140 degrees.

The bearing temperature generally cannot exceed 75 degrees, and the temperature rise does not exceed 45 degrees.