Novel efficient slurry conveying diaphragm pump

Abstract

The invention relates to the technical field of diaphragm pumps, and provides a novel efficient slurry conveying diaphragm pump which comprises a permanent magnet synchronous motor and a coupler, the rated rotating speed range of the permanent magnet synchronous motor is 42-50 r / min, a key groove connecting structure is arranged at the output shaft end of the motor, and the first connecting end of the coupler is connected with an output shaft of the permanent magnet synchronous motor through a flange; the second connecting end is connected with an input shaft of the diaphragm pump driving end through a bolt, the diaphragm pump driving end comprises a casting box body, a five-throw crankshaft arranged in the box body and five connecting rod mechanisms connected with the crankshaft, and through the arrangement of structures such as direct drive of a permanent magnet synchronous motor and the five-throw crankshaft, the five-cylinder crankshaft is directly driven by a low-speed large-torque permanent magnet motor; a traditional speed reducing mechanism is omitted, a transmission chain is simplified, energy loss is reduced, meanwhile, 72-degree phase distribution of the five-throw crankshaft enables displacement curves of the five cylinder bodies to be optimized and superposed, output flow pulsation is remarkably reduced structurally, efficient and stable conveying is achieved, and the problem that in the prior art, efficiency is insufficient is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of diaphragm pumps, in particular to a novel high-efficiency slurry conveying diaphragm pump. BACKGROUND

[0002] The slurry conveying diaphragm pump is a key equipment for conveying high-concentration and high-abrasion slurry materials in the fields of mining, metallurgy and chemical industry.

[0003] The conventional slurry conveying diaphragm pump widely used at present mainly has the following technical defects: in the aspect of the driving system, the conventional diaphragm pump generally adopts a multi-stage transmission scheme of asynchronous motor + speed reducer. The transmission chain is too long, contains multiple mechanical transmission links, and each link has energy loss, resulting in low overall transmission efficiency of the system. Especially in actual operation, since the equipment is often in non-rated working condition, the efficiency of the motor is further reduced when it operates at low load and low speed, causing significant energy waste. At the same time, the complex transmission structure also leads to large equipment size and increased maintenance cost. In the aspect of conveying stability, the conventional diaphragm pump mainly adopts a three-cylinder or double-cylinder structure, and its working principle determines that the instantaneous displacement of each working chamber changes periodically. This structural characteristic causes inherent pulsation of the output flow, which in turn causes pressure fluctuation in the conveying pipeline, easily causing pipeline system vibration. To alleviate this problem, external energy absorption devices are usually added to the pipeline, but the reliability of these devices directly affects the safe operation of the entire system. Especially in long-distance conveying conditions, once the energy absorption device fails, it may cause serious pipeline accidents. SUMMARY

[0004] The present application provides a novel high-efficiency slurry conveying diaphragm pump, which solves the problem of insufficient efficiency in the related art.

[0005] The technical scheme of the present application is as follows: a novel high-efficiency slurry conveying diaphragm pump, comprising a permanent magnet synchronous motor, the rated speed range of which is 42-50 r / min, and a key groove connection structure is arranged at the output shaft end of the motor; a coupling, a first connection end of which is connected with the output shaft of the permanent magnet synchronous motor through a flange, and a second connection end of which is connected with the input shaft of the driving end of the diaphragm pump through bolts; a diaphragm pump driving end, comprising a cast box, a five-throw crankshaft arranged in the box, and five connecting rod mechanisms connected with the crankshaft, the phase angles of the five crank throws of the crankshaft being uniformly distributed at 72°; a diaphragm pump fluid end, comprising five independent cylinder modules, each cylinder module comprising a cylinder sleeve, a piston, a hydraulic diaphragm chamber, an inlet slurry valve and an outlet slurry valve, the piston being connected with the connecting rod mechanism of the driving end through a cross head; The permanent magnet synchronous motor directly drives the rotation of the crankshaft of the driving end of the diaphragm pump through the coupling, without the need to set a speed reduction mechanism. The five cylinder modules are arranged in a straight line, the inlet valve of each cylinder module is connected with the slurry source through an inlet pipeline, and the outlet valve is connected with a conveying pipeline through an outlet pipeline. The detection system comprises an encoder installed on the shaft end of the motor, a pressure sensor and a flow sensor arranged on the outlet pipeline.

[0006] The slurry conveying method comprises the following steps: The permanent magnet synchronous motor is started to operate at a rotating speed of 42-50 r / min; The rotating torque of the motor is directly transmitted to the crankshaft of the diaphragm pump driving end through the shaft coupling; The crankshaft rotates at a set rotating speed, and the five connecting rods are driven to move by the five crank webs with a phase difference of 72°; The connecting rod mechanism converts the rotating motion of the crankshaft into the linear reciprocating motion of the piston; The piston reciprocates in the cylinder sleeve, and the diaphragm is periodically deformed by the hydraulic oil; When the piston moves backward, the inlet valve is opened, the outlet valve is closed, and the slurry is sucked into the diaphragm chamber; When the piston moves forward, the inlet valve is closed, the outlet valve is opened, and the slurry is discharged from the diaphragm chamber; The five cylinders complete the slurry suction and discharge actions in turn with a phase difference of 72°, forming continuous slurry output; The rotating speed and phase position of the crankshaft are monitored in real time through the encoder; The pressure change of the outlet pipeline is monitored through the pressure sensor; The flow value of the output slurry is monitored through the flow sensor; According to the monitored flow value, the rotating speed of the permanent magnet synchronous motor is adjusted to control the output flow of the diaphragm pump.

[0007] As a preferred scheme of the application, the rotating speed control of the permanent magnet synchronous motor adopts a variable frequency speed regulation mode, the output frequency of the frequency converter is adjusted to continuously adjust the rotating speed of the motor in the range of 42-50 r / min, the adjusting precision of the motor rotating speed is controlled within ±1 r / min, the encoder at the shaft end of the motor feeds back the rotating speed signal to the control system in real time to form a rotating speed closed loop control.

[0008] As a preferred scheme of the application, the phase control of the five cylinders is ensured by precise machining of the crankshaft, the crankshaft is forged from 42CrMo alloy steel, is subjected to quenching and tempering treatment and precise grinding, the phase angle tolerance of the five crank webs is controlled within ±0.5°, the shaft neck size tolerance of each crank web is controlled within IT6 level precision, and the concentricity between the main shaft neck and the crank web neck is controlled within 0.02 mm.

[0009] As a preferred scheme of the present application, the reciprocating movement of the piston is realized through a crosshead guide mechanism, the crosshead is arranged in a guide rail, the coaxiality of the guide rail and the center line of the cylinder sleeve is controlled within 0.05 mm, the piston rod is threadedly connected with the crosshead and is provided with a locking nut, and the matching gap between the piston and the cylinder sleeve is controlled within the range of 0.1-0.15 mm.

[0010] As a preferred scheme of the present application, the inlet valve and the outlet valve adopt a cone valve structure, the contact surface between the valve core and the valve seat is a 45° conical surface, the valve core adopts a hard alloy material, the valve seat adopts a stainless steel material, the opening and closing of the valve is controlled through a hydraulic driving system, the hydraulic driving pressure is set within the range of 2-4 MPa, and the response time of the opening and closing of the valve is controlled within the range of 0.1-0.2 seconds.

[0011] As a preferred scheme of the present application, the deformation control of the diaphragm is realized through the adjustment of the amount of hydraulic oil, each diaphragm chamber is provided with an oil amount compensation device, the oil amount compensation device comprises a cylinder, a piston and an oil compensation valve, when the deformation amount of the diaphragm exceeds a set range, the oil compensation valve is automatically opened to compensate the amount of oil, so that the deformation amount of the diaphragm is kept within a safe range.

[0012] As a preferred scheme of the present application, the superposition of the displacement curves of the five cylinders is realized through the phase angle distribution of the crankshaft, the instantaneous displacement curve of each cylinder is a sine wave function, five sine wave functions with a phase difference of 72° are superposed to form a total output flow curve, and the mathematical expression of the flow curve is wherein i=1-5, is the phase angle of each cylinder.

[0013] As a preferred scheme of the present application, the signal processing of the monitoring system is realized through a PLC controller, the encoder signal is collected through a high-speed counting module, the pressure sensor signal is collected through an analog input module, the flow sensor signal is collected through a pulse input module, the PLC controller calculates a control quantity according to the collected signals, and outputs a control signal to a frequency converter and a hydraulic driving system.

[0014] The working principle and beneficial effects of the present application are as follows: 1. Through the arrangement of the direct drive permanent magnet synchronous motor and the five-throw crankshaft structure, the present application directly drives the five-cylinder crankshaft by using a low-speed large-torque permanent magnet motor, omits the traditional speed reduction mechanism, simplifies the transmission chain, reduces energy loss, and simultaneously optimizes the superposition of the displacement curves of the five cylinders through the 72° phase distribution of the five-throw crankshaft, thereby significantly reducing the output flow pulsation from the structure and realizing high-efficiency and stable conveying.

[0015] 2、The application ensures the movement accuracy and reliable sealing through the cooperation of five independent cylinder modules, cross head guide mechanism and hydraulic diaphragm chamber, and realizes the real-time feedback of the encoder, pressure and flow sensor, and the closed-loop control of the motor speed and valve action through PLC, so as to ensure the long-term stable operation and self-adaptive adjustment of the system. BRIEF DESCRIPTION OF DRAWINGS

[0016] The application will be further described in detail below in combination with the drawings and specific embodiments.

[0017] Figure 1 It is a three-cylinder schematic diagram of the diaphragm pump body of the application; Figure 2 It is a three-cylinder side view of the diaphragm pump body of the application; Figure 3 It is a five-cylinder schematic diagram of the diaphragm pump body of the application; Figure 4 It is a five-cylinder side view of the diaphragm pump body of the application; Figure 5 It is a five-cylinder top view of the diaphragm pump body of the application; Figure 6 It is a permanent magnet synchronous motor characteristic comparison curve diagram of the application; Figure 7 It is a double-cylinder double-acting theoretical displacement and fluctuation diagram of the application; Figure 8 It is a three-cylinder single-acting theoretical displacement and fluctuation diagram of the application; Figure 9 It is a five-cylinder single-acting theoretical displacement and fluctuation diagram of the application; Figure 10 It is a three-cylinder single-acting theoretical displacement and fluctuation diagram of the application; Figure 11 It is a six-cylinder single-acting or three-cylinder double-acting theoretical displacement and fluctuation diagram of the application; Figure 12 It is a double-cylinder double-acting theoretical displacement and fluctuation diagram of the application.

[0018] In the figure: 1, permanent magnet synchronous motor; 2, shaft coupling; 3, diaphragm pump body; 31, diaphragm pump driving end; 32, diaphragm pump fluid end. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the application will be clearly and completely described below in combination with the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0020] EMBODIMENT like Figures 1-11 As shown, a novel high-efficiency slurry conveying diaphragm pump includes a permanent magnet synchronous motor 1 with a rated speed range of 42-50 r / min, and a keyway connection structure is provided at the output shaft end of the motor. The coupling 2 has its first connecting end connected to the output shaft of the permanent magnet synchronous motor 1 via a flange, and its second connecting end connected to the input shaft of the diaphragm pump drive end 31 via bolts; The diaphragm pump drive end 31 includes a cast housing, a five-crankshaft housed in the housing, and five connecting rod mechanisms connected to the crankshaft. The five crank phase angles of the crankshaft are evenly distributed at 72°. The diaphragm pump fluid end 32 includes five independent cylinder modules. Each cylinder module includes a cylinder liner, piston, hydraulic diaphragm chamber, slurry inlet valve and slurry outlet valve. The piston is connected to the linkage mechanism of the drive end through a crosshead. The permanent magnet synchronous motor 1 directly drives the crankshaft of the diaphragm pump drive end 31 to rotate through the coupling 2, without the need for a reduction gear mechanism; The five cylinder modules are arranged in a straight line. The slurry inlet valve of each cylinder module is connected to the slurry source through the inlet pipe, and the slurry outlet valve is connected to the conveying pipeline through the outlet pipe. The equipment also includes a detection system, including an encoder mounted on the motor shaft, a pressure sensor and a flow sensor installed on the outlet pipeline.

[0021] The permanent magnet synchronous motor 1 has a rated speed of 45 r / min and 16 poles. It adopts permanent magnet excitation. The output shaft end of the motor is machined with an ISO standard keyway. The keyway size is in accordance with GB / T1095. The coupling 2 is a diaphragm type flexible coupling. Its first connection end is connected to the output shaft of the permanent magnet synchronous motor 1 through a flange with a stop-and-position fit. The fit tolerance is H7 / h6. The second connection end is connected to the input shaft of the diaphragm pump drive end 31 through high-strength bolts. The diaphragm pump drive end 31 includes an HT250 cast housing, within which a five-crankshaft is installed. The crankshaft material is 42CrMo, tempered to a hardness of HRC28-32. The phase angle of the five cranks is controlled at 72°±0.5°, and the crank journal dimensional tolerance is IT6. Each crank is connected to the connecting rod mechanism via a sliding bearing made of copper-based alloy. The diaphragm pump fluid end 32 includes five independent cylinder modules made of QT600 ductile iron. Each cylinder module includes a cylinder liner, piston, hydraulic diaphragm chamber, inlet valve, and outlet valve. The piston rod is connected to the connecting rod mechanism of the drive end via a crosshead. The crosshead is guided by a guide rail made of GCr15 bearing steel.

[0022] The slurry delivery method includes the following steps: Start the permanent magnet synchronous motor and run it within a speed range of 42-50 r / min; The rotational torque of the motor is directly transmitted to the crankshaft at the drive end of the diaphragm pump via a coupling. The crankshaft rotates at a set speed, driving five linkage mechanisms through five cranks with a phase difference of 72°. The linkage mechanism converts the rotational motion of the crankshaft into the linear reciprocating motion of the piston; The piston reciprocates within the cylinder liner, and the diaphragm is driven by hydraulic oil to undergo periodic deformation. When the piston moves backward, the slurry inlet valve opens and the slurry outlet valve closes, and the slurry is drawn into the diaphragm chamber. When the piston moves forward, the slurry inlet valve closes and the slurry outlet valve opens, and the slurry is discharged from the diaphragm chamber. The five cylinders sequentially complete the slurry suction and discharge actions with a 72° phase difference, forming a continuous slurry output; The crankshaft's speed and phase position are monitored in real time using an encoder; Pressure changes in the outlet pipeline are monitored using a pressure sensor. The flow rate of the output slurry is monitored using a flow sensor. Based on the monitored flow rate, the speed of the permanent magnet synchronous motor is adjusted to control the output flow rate of the diaphragm pump.

[0023] First, start the permanent magnet synchronous motor and set the initial frequency to 15Hz through the frequency converter, so that the motor runs at a speed of 45r / min. The output torque of the motor is directly transmitted to the crankshaft at the drive end of the diaphragm pump through the coupling. The torque range transmitted by the coupling is 5000-8000N·m. When the crankshaft rotates, five cranks with a phase difference of 72° drive the connecting rod mechanism in sequence. The connecting rod mechanism converts the rotational motion into the linear reciprocating motion of the piston. The piston stroke is set to 200mm. During the suction stroke, the piston moves backward, the slurry inlet valve opens under negative pressure, and the slurry outlet valve remains closed. The slurry enters the diaphragm chamber through the inlet pipe, with the inlet pressure maintained at 0.1-0.3 MPa. During the discharge stroke, the piston moves forward, the slurry inlet valve closes, and the slurry outlet valve opens under pressure. The slurry is discharged through the outlet pipe, with the outlet pressure controlled at 2.5-4.0 MPa. The five cylinders operate sequentially with a 72° phase difference, forming a continuous slurry output. An incremental encoder mounted on the motor shaft end monitors the crankshaft speed and phase position in real time, with an encoder resolution of 1024 pulses / revolution. A piezoresistive pressure sensor monitors the outlet pipe pressure with an accuracy class of 0.5. An electromagnetic flowmeter monitors the output flow rate, with the measurement error controlled within ±1%.

[0024] The speed control of the permanent magnet synchronous motor adopts frequency conversion speed regulation. By adjusting the output frequency of the frequency converter, the motor speed can be continuously adjusted within the range of 42-50 r / min. The adjustment accuracy of the motor speed is controlled within ±1 r / min. The encoder at the end of the motor shaft feeds back the speed signal to the control system in real time, forming a closed-loop speed control.

[0025] A vector control frequency converter is used, with an output frequency range set to 5-50Hz. When flow rate adjustment is required, the PLC calculates the set speed and outputs a 4-20mA analog signal to the frequency converter. The frequency converter adjusts the output frequency according to the set value, while the actual speed is fed back through the encoder, forming a closed-loop control. The speed regulation adopts a PID algorithm with a proportional coefficient set to 0.8, an integral time set to 0.1s, and a derivative time set to 0.05s. The speed control accuracy is ensured by encoder feedback. The encoder outputs 1024 pulses per revolution, achieving a resolution of 4096 counting points per revolution through quadruple frequency counting. When a speed deviation exceeding ±2r / min is detected, the system automatically adjusts the PID parameters to ensure that the speed is stable within ±1r / min of the set value.

[0026] The phase control of the five cylinders is ensured by the precision machining of the crankshaft. The crankshaft is forged from 42CrMo alloy steel, and after quenching and tempering and precision grinding, the phase angle tolerance of the five cranks is controlled within ±0.5°, the journal size tolerance of each crank is controlled within IT6 grade precision, and the concentricity of the crankshaft main journal and the crank journal is controlled within 0.02mm.

[0027] The crankshaft blank is forged from 42CrMo alloy steel with a forging ratio controlled above 3. After tempering, it is first quenched at 850℃ for 2 hours, then tempered at 560℃ for 3 hours. Finishing is performed using a CNC crankshaft grinder with an 80# grinding wheel and a grinding feed controlled at 0.02mm / r. The phase angles of the five cranks are precisely controlled by an indexing head, achieving an indexing accuracy of ±0.1°. The journal dimensions are machined to IT6 grade, with roundness tolerance controlled within 0.005mm. The crankshaft dynamic balance grade is G6.3, with residual unbalance less than 50g·mm. The concentricity of the main journal and crank journals is ensured by grinding with a center rest support, with total runout controlled within 0.02mm. Assembly uses a hot-fitting process, with heating temperature controlled at 150-180℃ and interference fit of 0.03-0.05mm.

[0028] The reciprocating motion of the piston is achieved through a crosshead guide mechanism. The crosshead is set inside the guide rail, and the coaxiality between the center line of the guide rail and the cylinder liner is controlled within 0.05mm. The piston rod and the crosshead are connected by threads and are equipped with a locking nut. The clearance between the piston and the cylinder liner is controlled within the range of 0.1-0.15mm.

[0029] The crosshead is made of 45 steel with a surface hardening hardness of HRC45-50. The guide rail material is GCr15 with a hardening hardness of HRC58-62. The coaxiality of the center lines of the guide rail and cylinder liner is ensured by precision boring. During machining, the cylinder liner mounting surface is used as the reference, and all guide rail holes are machined in one clamping. The piston rod and crosshead are connected by fine thread with a thread specification of M64×2 and a fit grade of 6H / 6g. The lock nut adopts a double nut anti-loosening structure, and the preload torque is set to 300 N·m. The fit clearance between the piston and cylinder liner is ensured by grouping and matching. The piston outer diameter is grouped in 0.01 mm intervals, and the cylinder liner inner diameter is grouped in 0.01 mm intervals. The groups with a fit clearance in the range of 0.1-0.15 mm are selected for assembly. The piston rings adopt a three-combination seal and the material is filled polytetrafluoroethylene.

[0030] The slurry inlet valve and slurry outlet valve adopt a cone valve structure. The contact surface between the valve core and the valve seat is a 45° cone surface. The valve core is made of hard alloy material, and the valve seat is made of stainless steel material. The opening and closing of the valve is controlled by a hydraulic drive system. The hydraulic drive pressure is set in the range of 2-4MPa, and the valve opening and closing response time is controlled in the range of 0.1-0.2 seconds.

[0031] Both the slurry inlet and outlet valves adopt a cone valve structure. The valve core material is YG8 hard alloy with a heat treatment hardness of HRA89 or higher. The valve seat material is 2Cr13 stainless steel with a tempering hardness of HRC28-32. The contact surface between the valve core and the valve seat is machined into a 45° cone with a surface roughness of Ra0.4. The hydraulic drive system uses a proportional valve for control. The drive pressure is adjustable within the range of 2-4MPa via a pressure reducing valve. The valve opening and closing response time is controlled by adjusting the throttle valve, with the opening time set to 0.1s and the closing time set to 0.15s. The valve stroke is adjusted via a limit screw, with the stroke range controlled between 10-15mm. The sealing structure adopts a combined seal, including an O-ring and a polyurethane seal. The working pressure range covers 0-6MPa.

[0032] The deformation control of the diaphragm is achieved through hydraulic oil quantity adjustment. Each diaphragm chamber is equipped with an oil quantity compensation device, which includes an oil cylinder, a piston, and an oil replenishment valve. When the diaphragm deformation exceeds the set range, the oil replenishment valve automatically opens to compensate for the oil quantity and keep the diaphragm deformation within a safe range.

[0033] Each diaphragm chamber is equipped with an independent oil level compensation device. The compensation cylinder has a diameter of 50mm and a stroke of 30mm. The oil replenishment valve is a pilot-operated relief valve with an opening pressure set at 2.5MPa. When the diaphragm deformation exceeds ±10% of the rated value, the oil replenishment valve automatically opens to compensate for the oil level. Oil level monitoring is achieved through a displacement sensor with a range of 50mm and an accuracy of 0.1mm. The hydraulic oil used is No. 46 anti-wear hydraulic oil, and the oil temperature is controlled within the range of 40-60℃. The diaphragm material is nitrile rubber with a thickness of 6mm and an allowable strain range of 30%-40%. The safety protection system has dual redundancy. When the diaphragm deformation exceeds the limit, an alarm signal is first issued. If the diaphragm does not return to normal within 3 seconds, the machine automatically shuts down for protection.

[0034] The displacement curves of the five cylinder blocks are superimposed using the phase angle distribution of the crankshaft. The instantaneous displacement curve of each cylinder block is a sine wave function. The superposition of five sine wave functions with a phase difference of 72° forms the total output flow rate curve. The mathematical expression for the flow rate curve is: Where i = 1-5, This represents the phase angle of each cylinder.

[0035] The instantaneous displacement curves of the five cylinder blocks are optimized and superimposed using the phase angle distribution of the crankshaft. The displacement curve of each cylinder block is represented by a sine function: Q_i(t) = Where A is the maximum displacement of a single cylinder, ω is the crankshaft angular velocity, and φ_i is the phase angle of each cylinder, with values ​​of 0°, 72°, 144°, 216°, and 288° respectively. The total output flow curve is the superposition of five sine functions: With i=1-5, through optimized design, the superimposed flow fluctuation coefficient is controlled within 5%. In actual control, the flow signal is analyzed by Fourier transform. When a specific harmonic component is detected to exceed the standard, compensation is made by fine-tuning the motor speed. The compensation amount is controlled within ±2% of the rated speed.

[0036] The signal processing of the monitoring system is achieved by a PLC controller. Encoder signals are acquired through a high-speed counting module, pressure sensor signals are acquired through an analog input module, and flow sensor signals are acquired through a pulse input module. The PLC controller calculates the control quantity based on the acquired signals and outputs the control signal to the frequency converter and hydraulic drive system.

[0037] The PLC controller adopts a modular structure, including a CPU module, a digital input / output module, an analog input module, and a high-speed counting module. Encoder signals are acquired through the high-speed counting module, with a counting frequency of 100kHz. Pressure sensor signals are acquired through the analog input module, with a sampling frequency of 1kHz and a 12-bit ADC conversion. Flow sensor signals are acquired through the pulse input module, with a pulse width measurement accuracy of 0.1ms. Signal processing employs digital filtering algorithms, including moving average filtering and Kalman filtering. The control algorithm executes every 10ms. The output control signal is converted to an analog quantity through the DA module, with an output range of 0-10V. The system is equipped with three alarm levels: early warning, minor fault, and major fault, corresponding to different processing procedures and shutdown delays.

[0038] Working principle: The equipment uses a 16-pole permanent magnet synchronous motor with a rated speed of 45 r / min as the power source. The motor output shaft is connected to a diaphragm-type flexible coupling via an ISO standard keyway, achieving a flange connection with a tolerance of H7 / h6, directly transmitting 5000-8000 N·m torque to the diaphragm pump drive end. The drive end is equipped with a 42CrMo five-crankshaft that has undergone quenching and tempering treatment. The five cranks are precisely distributed with a phase angle of 72°±0.5°, driving the connecting rod mechanism through copper-based alloy sliding bearings, converting the rotary motion into the linear reciprocating motion of the piston. During motion transmission, the crosshead guide mechanism's guide rail and cylinder liner are coaxial with each other at 0.05mm to ensure precise alignment between the piston rod and cylinder liner. The clearance between the piston and cylinder liner is controlled within the range of 0.1-0.15mm through group selection. When the crankshaft rotates at a set speed, the five pistons act sequentially with a 72° phase difference: during the intake stroke, the piston moves backward, causing the slurry inlet valve to open under negative pressure, with an inlet pressure of 0.1-0.3MPa, allowing the slurry to enter the diaphragm chamber; during the discharge stroke, the piston moves forward, pushing the discharge valve to open with an outlet pressure of 2.5-4.0MPa, allowing the slurry to be discharged through the outlet pipeline. The slurry discharge action of the five cylinders is optimized through phase to form a continuous flow output, and its instantaneous discharge curve conforms to... Mathematical models enable flow fluctuation coefficients to be controlled within 5%; The system monitors crankshaft phase in real time using an incremental encoder with 1024 pulses / revolution, detects pipeline pressure using a 0.5-grade precision piezoresistive pressure sensor, and measures output flow rate using an electromagnetic flowmeter with ±1% precision. These signals are processed by the PLC control system with a sampling frequency of 1kHz and a control cycle of 10ms. A PID algorithm with a proportional coefficient of 0.8 and an integral time of 0.1s is used to adjust the motor speed via a vector frequency converter, achieving a control accuracy of ±1r / min. Simultaneously, each diaphragm chamber is equipped with an oil compensation device with a replenishment valve opening pressure of 2.5MPa. A displacement sensor monitors diaphragm deformation, automatically compensating for oil volume when the deformation exceeds the ±10% limit. The entire system utilizes a modular PLC to implement three-level alarm protection, ensuring stable operation of the equipment within an oil temperature range of 40-60℃, ultimately achieving efficient and stable slurry delivery.

[0039] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A novel, high-efficiency diaphragm pump for slurry transport, characterized in that, include: The permanent magnet synchronous motor 1) has a rated speed range of 42-50 r / min and a keyway connection structure is provided at the output shaft end of the motor. The coupling 2) has its first connecting end connected to the output shaft of the permanent magnet synchronous motor 1) via a flange, and its second connecting end connected to the input shaft of the diaphragm pump drive end 31) via bolts; The diaphragm pump drive end 31) includes a cast housing, a five-crankshaft housed in the housing, and five connecting rod mechanisms connected to the crankshaft, wherein the five crank phase angles of the crankshaft are evenly distributed at 72°. The diaphragm pump fluid end 32) includes five independent cylinder modules, each cylinder module including a cylinder liner, piston, hydraulic diaphragm chamber, slurry inlet valve and slurry outlet valve, the piston being connected to the linkage mechanism of the drive end via a crosshead; The permanent magnet synchronous motor 1) directly drives the crankshaft of the diaphragm pump drive end 31) to rotate through the coupling 2). The five cylinder modules are arranged in a straight line. The slurry inlet valve of each cylinder module is connected to the slurry source through the inlet pipe, and the slurry outlet valve is connected to the conveying pipeline through the outlet pipe. It also includes a detection system, including an encoder mounted on the motor shaft, a pressure sensor and a flow sensor installed on the outlet pipeline.

2. The novel high-efficiency slurry conveying diaphragm pump according to claim 1, characterized in that: The slurry delivery method of the novel high-efficiency slurry delivery diaphragm pump includes the following steps: Start the permanent magnet synchronous motor and run it within a speed range of 42-50 r / min; The rotational torque of the motor is directly transmitted to the crankshaft at the drive end of the diaphragm pump via a coupling. The crankshaft rotates at a set speed, driving five linkage mechanisms through five cranks with a phase difference of 72°. The linkage mechanism converts the rotational motion of the crankshaft into the linear reciprocating motion of the piston; The piston reciprocates within the cylinder liner, and the diaphragm is driven by hydraulic oil to undergo periodic deformation. When the piston moves backward, the slurry inlet valve opens and the slurry outlet valve closes, and the slurry is drawn into the diaphragm chamber. When the piston moves forward, the slurry inlet valve closes and the slurry outlet valve opens, and the slurry is discharged from the diaphragm chamber. The five cylinders sequentially complete the slurry suction and discharge actions with a 72° phase difference, forming a continuous slurry output; The crankshaft's speed and phase position are monitored in real time using an encoder; Pressure changes in the outlet pipeline are monitored using a pressure sensor. The flow rate of the output slurry is monitored using a flow sensor. Based on the monitored flow rate, the speed of the permanent magnet synchronous motor is adjusted to control the output flow rate of the diaphragm pump.

3. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The speed control of the permanent magnet synchronous motor adopts frequency conversion speed regulation. By adjusting the output frequency of the frequency converter, the motor speed can be continuously adjusted within the range of 42-50 r / min. The adjustment accuracy of the motor speed is controlled within ±1 r / min. The encoder at the end of the motor shaft feeds back the speed signal to the control system in real time, forming a closed-loop speed control.

4. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The phase control of the five cylinders is ensured by the precision machining of the crankshaft. The crankshaft is forged from 42CrMo alloy steel, and after quenching and tempering and precision grinding, the phase angle tolerance of the five cranks is controlled within ±0.5°, the journal size tolerance of each crank is controlled within IT6 grade precision, and the concentricity of the crankshaft main journal and the crank journal is controlled within 0.02mm.

5. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The reciprocating motion of the piston is achieved through a crosshead guide mechanism. The crosshead is set inside the guide rail, and the coaxiality between the center line of the guide rail and the cylinder liner is controlled within 0.05mm. The piston rod and the crosshead are connected by threads and are equipped with a locking nut. The clearance between the piston and the cylinder liner is controlled within the range of 0.1-0.15mm.

6. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The slurry inlet valve and slurry outlet valve adopt a cone valve structure. The contact surface between the valve core and the valve seat is a 45° cone surface. The valve core is made of hard alloy material, and the valve seat is made of stainless steel material. The opening and closing of the valve is controlled by a hydraulic drive system. The hydraulic drive pressure is set in the range of 2-4MPa, and the valve opening and closing response time is controlled in the range of 0.1-0.2 seconds.

7. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The deformation control of the diaphragm is achieved through hydraulic oil quantity adjustment. Each diaphragm chamber is equipped with an oil quantity compensation device, which includes an oil cylinder, a piston, and an oil replenishment valve. When the diaphragm deformation exceeds the set range, the oil replenishment valve automatically opens to compensate for the oil quantity and keep the diaphragm deformation within a safe range.

8. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The displacement curves of the five cylinder blocks are superimposed using the phase angle distribution of the crankshaft. The instantaneous displacement curve of each cylinder block is a sine wave function. The superposition of five sine wave functions with a phase difference of 72° forms the total output flow rate curve. The mathematical expression for the flow rate curve is: Where i = 1-5, This represents the phase angle of each cylinder.

9. The novel high-efficiency slurry conveying diaphragm pump according to claim 2, characterized in that: The signal processing of the monitoring system is achieved by a PLC controller. Encoder signals are acquired through a high-speed counting module, pressure sensor signals are acquired through an analog input module, and flow sensor signals are acquired through a pulse input module. The PLC controller calculates the control quantity based on the acquired signals and outputs the control signal to the frequency converter and hydraulic drive system.

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