CN100590317C - A single-stage turbo vacuum machine and its vacuum pumping method - Google Patents

Abstract

The invention discloses a single-stage turbo vacuum machine and a vacuum pumping method using the same. The pump body of the turbo vacuum machine is installed on one side of the turbo acceleration gear box, and the inlet shell is embedded in the volute. The inner wall forms the suction inlet and the static ring of the impeller. The suction inlet adopts a conical structure. The inlet shell at the rear end of the suction inlet adopts a circular arc shape at the matching position with the impeller to form the static ring of the impeller. At the outlet of the impeller, the rear part of the static ring of the impeller The annular cavity between the inlet casing and the volute forms a diffuser, and the diffuser guide blades are installed in the diffuser. The method of extracting vacuum is that the impeller is driven by the turbine acceleration gear box, so that the gas is sucked from the suction port, passes through the impeller, diffuser and guide vanes, and is discharged from the discharge port of the volute; a vacuum degree of -20KPa to -60KPa is formed at the suction port , to achieve vacuum extraction, the vacuum extraction method has high efficiency, which can reach more than 80%. Compared with the conventional vacuum system, it can reduce energy consumption by 50%.

Description

A single-stage turbo vacuum machine and its vacuum pumping method

technical field

The invention relates to the field of turbo machinery technology and vacuum equipment, in particular to a single-stage turbo vacuum machine and a vacuum extraction method using the same.

Background technique

Vacuum systems that require large pumping capacity are widely used in petroleum, chemical, mining, machinery, light industry, food, medicine, electronics, metallurgy, aerospace and other departments. At present, the vacuum systems that are widely used are mainly water ring vacuum pumps and Luo tz vacuum pump.

The water ring vacuum pump belongs to the variable capacity vacuum pump. When working, a certain amount of water is required in the pump body as the working fluid. The impeller of the vacuum pump drives the water to rotate to produce a change in the volume of the pump chamber to realize the working process of suction, compression and exhaust. With the existence of working fluid, the speed of the pump is low, and the working efficiency is also low, generally around 40%. The water ring vacuum pump is limited by the structure and the saturated vapor pressure of the working fluid. Due to the high saturated vapor pressure of water, the suction pressure of the water ring vacuum pump is also high, and the degree of vacuum generated will also be reduced.

The Roots vacuum pump is a rotary variable displacement vacuum pump, which is evolved from the Roots blower. The Roots vacuum pump has a high pumping rate at a low inlet pressure, and has the characteristics of small driving power, compact structure, small footprint and low operation and maintenance costs, but the Roots vacuum pump is a vacuum pump without internal compression. , usually the compression ratio is very low, so when it is used in high and medium vacuum systems, it must be used in conjunction with the backing vacuum pump. The Roots vacuum pump can start to work, and in general, the Roots vacuum pump does not allow high pressure difference to work, otherwise it will be damaged due to overload and overheating.

In the current water ring vacuum pump and Roots vacuum pump systems, there are generally disadvantages of low working efficiency, especially in vacuum situations that require large pumping volumes, the number of vacuum pumps required is large, large in size, high in energy consumption, and loud in noise.

Contents of the invention

In order to overcome the disadvantages of large energy consumption and water consumption of the existing vacuum system with large pumping volume, the present invention provides a single-stage turbo vacuum machine.

Another object of the present invention is to provide a method for extracting vacuum using the single-stage turbo vacuum machine.

The purpose of the present invention is achieved through the following technical solutions:

A single-stage turbo-vacuum machine, including a turbo-accelerating gearbox, a pump body and an impeller assembly; the large gear in the turbo-accelerating gearbox meshes with the pinion, the shaft on the bull gear is connected to the prime mover, and the pinion The output end of the shaft is connected with the impeller; the pump body is installed on one side of the turbine acceleration gearbox, including the inlet casing, the volute, the diffuser guide blade and the blade angle adjustment mechanism; the inlet casing is embedded in the volute In the shell, the inner wall forms the suction inlet and the impeller static ring. The suction inlet adopts a conical structure. The inlet shell at the rear end of the suction inlet adopts an arc shape at the matching position with the impeller to form the impeller static ring. The impeller and the impeller static ring adopt a gap Coordinated, the shape of the inner wall of the volute adopts a circular arc cross-section, and its diameter gradually increases along the direction of airflow rotation. At the outlet of the impeller, the annular cavity between the inlet housing at the rear of the impeller static ring and the volute forms a diffuser. The diffuser guide vanes are installed in the diffuser; the blade angle adjustment mechanism is installed behind the diffuser guide vanes, including blade connection blocks, block fixing pins, rings, rod fixing pins, connecting rods, lifting lugs, Pneumatic membrane actuator, each diffuser and guide vane is connected to the ring through a corresponding blade connecting block and block fixing pin, and the pneumatic membrane actuator is connected to the ring through successively connected lifting lugs, connecting rods and rod fixing pins ; The impeller assembly includes an impeller and a pinion shaft, and the impeller is installed at the end of the pinion shaft of the turbo speed-up gearbox and is located in the cavity in the suction port.

Further, the impeller is a semi-open centrifugal three-dimensional flow structure, and the diameter of the impeller is preferably 400mm to 800mm.

The number of the diffuser guide vanes is preferably 24 to 30, and the number is evenly distributed around the circumference.

The angle of the diffuser and guide vane is adjustable, and the angle adjustment range is 8 degrees to 30 degrees.

The bull gear and the pinion of the described turbo acceleration gear box adopt double helical gears with left and right rotations.

The pump body also includes an air shaft seal installed between the volute and the pinion shaft.

The single-stage turbo vacuum machine also includes an oil supply assembly, which is installed on the turbine acceleration gearbox, including an oil pump transmission gear pair, a mechanical lubricating oil pump, and a gear of the oil pump transmission gear pair is installed on the mechanical lubricating oil pump. On the shaft, another gear is installed on the shaft of the large gear, and the shaft of the large gear drives the oil pump transmission gear pair to run, driving the mechanical lubricating oil pump to run.

The method of vacuum extraction using a single-stage turbine vacuum machine: the impeller is driven by the turbine acceleration gearbox and rotates at a speed of 4000r/min to 12000r/min, so that the gas is sucked from the suction port, passes through the impeller, diffuser and guide vanes, and flows from the The discharge port of the volute is discharged; the flow rate of the suction gas is 500m ³ /min to 1500m ³ /min, and a vacuum degree of -20KPa to -60KPa is formed at the suction port to realize vacuum extraction.

Further, the temperature of the gas discharged from the outlet of the volute is 100° C. to 180° C., and the heat energy recovery is realized through the heat exchanger.

Compared with the prior art, the present invention has the following advantages and beneficial effects:

The invention utilizes the high-speed rotation of the single-stage turbine impeller to realize the large-flow suction of the gas to generate vacuum, which can form a vacuum degree of -20KPa to -60KPa, with high efficiency, generally reaching more than 80%. Compared with conventional vacuum systems, It can reduce energy consumption by 50%, and the angle of the diffuser guide vane can be automatically adjusted according to the vacuum state of the system, and the power consumption also changes with the change of system vacuum, so that the vacuum turbine can work at the maximum efficiency; The turbo vacuum machine is compressed, and the exhaust temperature reaches 100-180°C, and the heat energy can be recovered through the heat exchanger; the turbo vacuum machine does not need sealing water during operation, which can save a lot of water; due to the compact structure of the turbo vacuum machine, The vacuum capacity is large. Compared with the conventional vacuum system, the number of vacuum machines required is reduced and the space occupied by the equipment is reduced; the turbo vacuum machine is lubricated by a mechanical lubricating oil pump, which provides the greatest operational safety for the turbo vacuum machine.

Description of drawings

Fig. 1 is a schematic structural view of a single-stage turbo vacuum machine of the present invention.

FIG. 2 is a partial enlarged view of A in FIG. 1 .

Fig. 3 is a B-B sectional view of Fig. 1 .

As shown in the figure, 1. Suction inlet 2. Impeller 3. Impeller static ring 4. Inlet casing 5. Volute 6. Discharge outlet 7. Diffuser guide vane 8. Air shaft seal 9. Turbine acceleration gearbox 10 .pinion shaft 11.pinion 12.oil pump transmission gear pair 13.mechanical lubricating oil pump 14.prime mover 15.big gear 16.blade connecting block 17.block fixing pin 18.ring 19.rod fixing pin 20.connecting rod 21. Lifting lug 22. Pneumatic film actuator

Detailed ways

In order to further understand the present invention, the present invention will be further described below in conjunction with the accompanying drawings. It should be noted that the specific embodiments do not limit the protection scope of the present invention.

Example 1:

As shown in Figure 1, the single-stage turbo vacuum machine includes a turbo acceleration gearbox 9, a pump body, an impeller assembly, and an oil supply assembly; the turbo acceleration gearbox 9 is provided with a large gear 15 and a pinion 11 that mesh with each other , the shaft on the bull gear 15 is connected with the prime mover 14, the output end of the pinion shaft 10 is connected with the impeller 2, and the pinion 11 is driven by the bull gear 15 to realize the speed increase. The large gear 15 and the pinion 11 of the turbine acceleration gearbox preferably adopt a double helical gear structure with left and right rotations, and the axial thrust generated by the impeller 2 can be offset by utilizing the characteristics of the double helical gears. The pump body is installed on one side of the turbine acceleration gearbox 9, including the inlet casing 4, the volute 5, the diffuser guide vane 7, the blade angle adjustment mechanism and the air shaft seal 8; the inlet casing 4 is embedded in the volute 5 , the inner wall is integrally processed to form the suction port 1 and the impeller static ring 3, the suction port 1 is a conical structure, and the inlet housing 4 on the side of the suction port 1 close to the turbine acceleration gearbox 9 is a circular arc at the matching position with the impeller 2 Shaped to form the impeller static ring 3, such a conical shape combined with a circular arc-shaped intake structure forms the smallest intake vortex area; the impeller 2 and the impeller static ring 3 adopt clearance fit; the inner wall shape of the volute 5 adopts a circular arc Shaped cross-section, its diameter gradually increases along the direction of airflow rotation; at the outlet of the impeller 2, the annular cavity between the rear of the impeller static ring 3 of the inlet housing 4 and the volute 5 forms a diffuser, and the diffuser guide Flow vanes 7 are installed in the diffuser. Figure 2 shows the blade angle adjustment mechanism, and Figure 3 shows the blade angle adjustment mechanism and the distribution of the diffuser guide vanes. The blade angle adjustment mechanism is installed behind the diffuser guide blade 7, as shown in Figure 2 and Figure 3, including blade connecting block 16, block fixing pin 17, ring 18, rod fixing pin 19, connecting rod 20, lifting lug 21. Pneumatic membrane actuator 22; each diffuser guide vane 7 is connected to the ring 18 through a corresponding blade connection block 16 and block fixing pin 17, and the pneumatic membrane actuator 22 is connected to The rod 20 and the rod fixing pin 19 are connected with the ring 18, and the pneumatic film actuator 22 moves up and down, driving the ring 18 to move in a circular arc, thereby driving the diffuser guide vane 7 to move, and realizing the angle adjustment of the diffuser guide vane 7 , the number of 7 diffuser guide vanes is preferably 24 to 30, evenly distributed along the circumference, the angle adjustment range is 8 degrees to 30 degrees, by changing the angle of the diffuser guide vanes 7, the suction volume of the turbo vacuum machine can be adjusted , so that the degree of vacuum can be adjusted. The air shaft seal 8 is installed between the volute 5 and the pinion shaft 10 . The impeller assembly includes an impeller 2 and a pinion shaft 10. The impeller 2 is installed at the end of the pinion shaft 10 of the turbine acceleration gearbox 9. The impeller 2 adopts a semi-open centrifugal three-way flow structure to improve the pumping capacity of the impeller. The impeller diameter is preferably 400 mm to 800 mm. The oil supply assembly is installed on the turbine acceleration gearbox 9, including the oil pump transmission gear pair 12 and the mechanical lubricating oil pump 13. Gear is installed on the axle of mechanical lubricating oil pump 13, and another gear is installed on the axle of bull gear 15, and the axle drive oil pump transmission gear pair 12 of bull gear 15 runs, and drives mechanical lubricating oil pump 13 operation. Bearings and gears of the turbine acceleration gearbox 9 are lubricated with thin oil. When starting up, at first an electric auxiliary lubricating oil pump provides lubrication for the turbine acceleration gear box 9, and after the turbine acceleration gear box 9 runs normally, the turbine acceleration gear box 9 simultaneously drives the mechanical lubricating oil pump 13 to also run normally, providing the turbine The flat acceleration gearbox 9 provides lubrication, and the electric auxiliary lubricating oil pump stops working. Under normal operation, the lubricating oil is mainly provided by the mechanical lubricating oil pump 13. When shutting down, because the turbine acceleration gearbox 9 begins to decelerate, the oil supply capacity of the mechanical lubricating oil pump 13 is not enough, and the electric auxiliary lubricating oil pump starts to work. The combination of a mechanical lubricating oil pump 13 and an electric auxiliary lubricating oil pump provides maximum operational safety for turbo vacuum machines.

The method of extracting vacuum in a single-stage turbo vacuum machine: the impeller 2 is driven by the pinion shaft 10 of the turbine acceleration gearbox 9, and rotates at a high speed of 4000r/min, so that the gas is sucked from the suction port 1, and the gas entering the impeller 2 is drawn The blades of the impeller 2 rotate at a high speed, which increases the kinetic energy and static pressure head, and then exits the impeller 2 and enters the diffuser, where the kinetic energy of the gas is transformed into potential energy, and its pressure and temperature rise rapidly, and finally enters the worm The shell 5 is discharged from the discharge port 6 of the volute 5, and the temperature of the discharged gas is 100°C. At the suction port 1 of the turbo vacuum machine, the flow rate of the suction gas is 500m ³ /min, forming a vacuum degree of -20KPa to realize vacuum extraction.

Example 2:

Vacuum extraction method of single-stage turbine vacuum machine: impeller 2 is driven by pinion shaft 10 of turbine acceleration gearbox 9, and rotates at a high speed of 12000r/min, so that the gas is sucked from suction port 1, and the gas entering impeller 2 is drawn The blades of the impeller 2 rotate at a high speed, which increases the kinetic energy and static pressure head, and then exits the impeller 2 and enters the diffuser, where the kinetic energy of the gas is transformed into potential energy, and its pressure and temperature rise rapidly, and finally enters the worm The shell 5 is discharged from the discharge port 6 of the volute 5, and the temperature of the discharged gas is 180°C. At the suction port 1 of the turbo vacuum machine, the flow rate of the suction gas is 1500m ³ /min, forming a vacuum degree of -60KPa to realize vacuum extraction.

If the strength and processing accuracy of the gear shaft and the large and small gears allow, the single-stage turbine vacuum system of the present invention can also realize that a turbine acceleration gear box symmetrically drives two pump bodies and impeller assemblies, or four pump bodies and impeller assembly.

Claims (9)

1. a single stage turbine vacuum machine is characterized in that: comprise turbine acceleration gear box, the pump housing and impeller assembly; Gearwheel and pinion in the described turbine acceleration gear box, the axle on the gearwheel connects with prime mover, and the output terminal of pinion shaft connects with impeller; The described pump housing is installed in a side of turbine acceleration gear box, comprises suction casing, spiral case, diffusion guide vane and blade angle controlling mechanism; Described suction casing is embedded in the spiral case, its inwall forms suction port and impeller stationary ring, suction port adopts conical structure, the suction casing that is positioned at the suction port rear end is adopting circular arc with the impeller cooperation position, form the impeller stationary ring, impeller and impeller stationary ring adopt Spielpassung, the inner wall shape of spiral case adopts circular section, its diameter increases gradually along the air-flow sense of rotation, at the impeller outlet place, the suction casing at impeller stationary ring rear portion and the annular housing between the spiral case form Diffuser, and the diffusion guide vane is installed in the Diffuser; The blade angle controlling mechanism is installed in the back of diffusion guide vane, comprise blade contiguous block, piece fixing pin, annulus, bar fixing pin, connecting rod, hanger, air bladder final controlling element, each diffusion guide vane is connected with annulus with the piece fixing pin by a blade contiguous block corresponding with it, and the air bladder final controlling element is connected with annulus by hanger, connecting rod and the bar fixing pin that links to each other successively; Described impeller assembly comprises impeller, pinion shaft, and impeller is installed in the end of the pinion shaft of turbine acceleration gear box, is positioned at the cavity of suction port.

2. single stage turbine vacuum machine according to claim 1 is characterized in that: described impeller is the centrifugal three-dimensional flow structure of semi-open type, and impeller diameter is 400mm to 800mm.

3. single stage turbine vacuum machine according to claim 1 is characterized in that: described diffusion guide vane number is 24 to 30, and circumference evenly distributes.

4. single stage turbine vacuum machine according to claim 3 is characterized in that: described diffusion guide vane adjustable angle, angle of regulation range 8 degree are to 30 degree.

5. according to each described single stage turbine vacuum machine of claim 1-4, it is characterized in that: the diclinic gear that the gearwheel of described turbine acceleration gear box and small gear revolve about adopting.

6. according to each described single stage turbine vacuum machine of claim 1-4, it is characterized in that: the described pump housing also comprises gas axle envelope, and gas axle envelope is installed between spiral case and the pinion shaft.

7. according to each described single stage turbine vacuum machine of claim 1-4, it is characterized in that: described single stage turbine vacuum machine also comprises the fuel feeding assembly, the fuel feeding assembly is installed on the turbine acceleration gear box, comprise oil pump driving gear pair, mechanical lubrication oil pump, a gear of oil pump driving gear pair is installed on the axle of mechanical lubrication oil pump, the another one gear is installed on the axle of gearwheel, and the axle of gearwheel drives the secondary running of oil pump driving gear, drives the machine oil pump operation.

8. application rights requires 1 described single stage turbine vacuum machine method for extracting vacuum, it is characterized in that: impeller drives by turbine acceleration gear box, rotating speed rotation with 4000r/min to 12000r/min, gas is sucked from suction port, through impeller, diffusion guide vane, discharge from the spiral case exhaust port; The flow that sucks gas is 500m ³/ min to 1500m ³/ min in the degree of vacuum of the formation-20KPa of suction port place to-60KPa, realizes the extraction of vacuum.

9. application single stage turbine vacuum machine method for extracting vacuum according to claim 8 is characterized in that: the gas temperature of discharging from the exhaust port of spiral case is 100 ℃ to 180 ℃, realizes energy recovery by heat exchanger.

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