附件244 Contents(目录) Instructor of Experimental Projects (English).-20 实验指导书(中文)21-32
附件 24.4 1 Contents(目录) Instructor of Experimental Projects(English).2-20 实验指导书(中文).21-32
附件24.4 Experiment 1 Experiment of assembling gear pump of CB type 1.General description The greatest advantages of gear pumps are:small size.light weight,reliable.easy to manufacture,low cost and less sensitive to pollution of hydraulic oil,convenient maintenance and repair,etc.Consequently,gear pumps are found widely applications in low-pressure hydraulic system(general in 25 kg/cm2 or less).The shortages of gear pumps are that it has more leakage-level and the gear bearing undertake larger pressure which lead the gear pump to be only applicable to low-pressure hydraulic system.As a result of large flow pulsation and pressure pulsation,very favorable low sound levels can not be achieved.what's more,it can only be used as a fixed delivery pump.But,as some structural improvement measures are taken in the gear pumps.it can reach a higher working pressure CB-type gear pump is designed and manufactured by own designers and manufacturing engineers in our country.It's working pressure is 25 kg/cm2.We make a little improvement in the structure to accommodate the needs of the high-pressure hydraulic system (to realize the automatic compensation of the axial clearance such as a floating bushing or a floating sideboard is set between the gears and the front and rear covers in the gear pumps with high pressure).So we can make the outlet pressure of the gear pumps to reach 70~140kg/cm2 By considering the structure of gear pumpsWe can satisfactorily resolve the problem of axial clearance.Unbalanced hydraulic radial force,Phenomenon of surrounded oil and so on. 2.The purpose of the experiment Understand the Principle of assembly and structural characteristics of CB-type gear pumps 3.Equipment of experimental CB-type gear pump,OB-B-type gear pump,CB-G-type gear pump,CB-H-type gear pump
附件 24.4 2 Experiment 1 Experiment of assembling gear pump of CB type 1、General description The greatest advantages of gear pumps are: small size, light weight, reliable, easy to manufacture, low cost and less sensitive to pollution of hydraulic oil, convenient maintenance and repair, etc. Consequently, gear pumps are found widely applications in low-pressure hydraulic system( general in 25 kg / cm 2 or less) .The shortages of gear pumps are that it has more leakage-level and the gear bearing undertake larger pressure which lead the gear pump to be only applicable to low-pressure hydraulic system. As a result of large flow pulsation and pressure pulsation ,very favorable low sound levels can not be achieved. what’s more , it can only be used as a fixed delivery pump.But ,as some structural improvement measures are taken in the gear pumps,it can reach a higher working pressure. CB-type gear pump is designed and manufactured by own designers and manufacturing engineers in our country.It’s working pressure is 25 kg / cm 2 . We make a little improvement in the structure to accommodate the needs of the high-pressure hydraulic system (to realize the automatic compensation of the axial clearance such as a floating bushing or a floating sideboard is set between the gears and the front and rear covers in the gear pumps with high pressure). So we can make the outlet pressure of the gear pumps to reach 70~140kg / cm 2. By considering the structure of gear pumps ,We can satisfactorily resolve the problem of axial clearance, Unbalanced hydraulic radial force ,Phenomenon of surrounded oil and so on. 2、The purpose of the experiment Understand the Principle of assembly and structural characteristics of CB-type gear pumps. 3、Equipment of experimental CB-type gear pump, OB-B-type gear pump ,CB-G-type gear pump, CB-H-type gear pump
附件24.4 4 The points for assembly and notes for attention (1)Select components carefully and keep them clean (2)Can not change the shape of every parts such as rounding chamfer,Round Edges and so on. (3)Needles which can not be left out should be filled with the inner ring of the Bearing Block.Needle bearing should be pressed into the vertical hole of the front and rear covers Needles should be flexible to rotate in the Bearing retainer (4)When parallel key of the Minor axis and long axis matches with the gear,their lateral clearance should not be too large.Of course,top surface can not be a collision and friction and Shaft and gears can be easy to promote within.What's more.Axis should not produce the phenomenon of radial swing in gear (5)CB-type gear pumps have 0.13~0.16 mm for the radial clearance and 0.03 mm for the axial clearance. (6)Rotating the Driving shaft(long axis)after the gear pumps is Completed assembled.To ensure that it is rotated by hand without let or hindrance. (7)Should pay attention to switch of lateral plate and it's Installation position for the high-pressure pumps with automatic compensating device to oil pressure. (8)Laboratory report for assembling gear pump of CB Type Experimental date Indoor temperature_ Major Class _Group_ Name Advisor Answer the following questions
附件 24.4 3 4、The points for assembly and notes for attention (1) Select components carefully and keep them clean (2) Can not change the shape of every parts such as rounding chamfer, Round Edges and so on. (3) Needles which can not be left out should be filled with the inner ring of the Bearing Block. Needle bearing should be pressed into the vertical hole of the front and rear covers. Needles should be flexible to rotate in the Bearing retainer. (4) When parallel key of the Minor axis and long axis matches with the gear, their lateral clearance should not be too large. Of course, top surface can not be a collision and friction and Shaft and gears can be easy to promote within. What’s more, Axis should not produce the phenomenon of radial swing in gear. (5) CB-type gear pumps have 0.13 ~ 0.16 mm for the radial clearance and 0.03 mm for the axial clearance. (6) Rotating the Driving shaft (long axis) after the gear pumps is Completed assembled. To ensure that it is rotated by hand without let or hindrance. (7) Should pay attention to switch of lateral plate and it’s Installation position for the high-pressure pumps with automatic compensating device to oil pressure. (8) Laboratory report for assembling gear pump of CB Type Experimental date_._._ Indoor temperature_ Major_ Class _ Group_ Name_ Advisor_ Answer the following questions
附件24.4 (1)What is the relationship between the rotation direction of gear pump with it's location of suction and displacement port? (2)State points that how the gear pumps solve the problem of unbalanced hydraulic radial force and Phenomenon of surrounded oil by observing the structure of it (3)What are the main factors which impact the gear pump to raise the working pressure? What Corresponding measures should be taken for High-pressure gear pump structure in generally Experiment 2 Experiment of assembling vane pumps of YB type 1.General deseription The greatest advantages of gear pumps are:smooth movement,low noise,large flow pulsation and high volumetric efficiency.But it also has some shortages,such as Poor performance of self-priming suction,Speed should not be too high,Sensitive to the pollution hydraulic oil,Complex structure and soon Vane pumps may be either of the single-acting or double-acting type.The former could be used for variable displacement pumps with lower pressure While the latter for fixed displacement pumps with the working pressure reaching to 65~140 kg/cm2 YB-type Vane pump is a double-acting pumps with good performance,which is designed and manufactured by own designers and manufacturing engineers in our country.It's greatest advantages are that YB-type Vane pump has symmetrical structure to bear counterbalance so that rotor bears litter radial force.The pressure of YB-type Vane pump can reach to 63 kg/cm2and the volumetric efficiency can reach to9% 2.The purpose of the experiment X
附件 24.4 4 (1) What is the relationship between the rotation direction of gear pump with it’s location of suction and displacement port? (2) State points that how the gear pumps solve the problem of unbalanced hydraulic radial force and Phenomenon of surrounded oil by observing the structure of it (3) What are the main factors which impact the gear pump to raise the working pressure? What Corresponding measures should be taken for High-pressure gear pump structure in generally. Experiment 2 Experiment of assembling vane pumps of YB type 1. General description The greatest advantages of gear pumps are: smooth movement, low noise, large flow pulsation and high volumetric efficiency. But it also has some shortages, such as Poor performance of self-priming suction, Speed should not be too high, Sensitive to the pollution hydraulic oil, Complex structure and so on . Vane pumps may be either of the single-acting or double-acting type. The former could be used for variable displacement pumps with lower pressure While the latter for fixed displacement pumps with the working pressure reaching to 65~140 kg / cm 2 . YB-type Vane pump is a double-acting pumps with good performance, which is designed and manufactured by own designers and manufacturing engineers in our country. It’s greatest advantages are that YB-type Vane pump has symmetrical structure to bear counterbalance so that rotor bears litter radial force. The pressure of YB-type Vane pump can reach to 63 kg / cm 2 and the volumetric efficiency can reach to 90% 2. The purpose of the experiment
附件24.4 Understand the Principle of assembly and structural characteristics of YB-type Vane pumps. 3.Equipment of experimental Several YB-type Vane pump for assembly 4.The points for assembly and notes for attention (1)The parts must be carefully cleaned to ensure that it does not contain any cutting chip and other pollutants before assembling (2)Vane can rotate in internal slot of rotor flexibly and freely.The clearance between them is0.015~0.025mm (3)The height of vane is0.005 mm which is lower than that of rotor. (4)The rotor and stator should be maintained in the direction of the original.Convince that the installation is not reversed (5)Control the Axial clearance in the scope of .04~0.07mm. (6)when tightening the Screw,force should be uniform. (7)Rotating the driving shaft after the gear pumps is completed assembled to ensure that it is rotated by hand without let or hindrance (8)Laboratory report for assembling Vane pumps of YB type Experimental date Indoor temperature Major Class _Group Name Advisor Answer the following questions 1 What is the main difference between the single-acting and double-acting vane pumps? 5
附件 24.4 5 Understand the Principle of assembly and structural characteristics of YB-type Vane pumps. 3. Equipment of experimental Several YB-type Vane pump for assembly 4. The points for assembly and notes for attention (1) The parts must be carefully cleaned to ensure that it does not contain any cutting chip and other pollutants before assembling. (2) Vane can rotate in internal slot of rotor flexibly and freely. The clearance between them is 0.015~0.025 mm . (3) The height of vane is 0.005 mm which is lower than that of rotor. (4) The rotor and stator should be maintained in the direction of the original. Convince that the installation is not reversed. (5) Control the Axial clearance in the scope of 0.04 ~ 0.07 mm. (6) when tightening the Screw ,force should be uniform. (7) Rotating the driving shaft after the gear pumps is completed assembled to ensure that it is rotated by hand without let or hindrance (8) Laboratory report for assembling Vane pumps of YB type Experimental date_._._ Indoor temperature_ Major_ Class _ Group_ Name_ Advisor_ Answer the following questions 1、What is the main difference between the single-acting and double-acting vane pumps?
附件24.4 2What kinds of curves does the stator of vane pump consists of?Why could double-acting vane pumps be used for fixed displacement pumps? 3,Observe the single-acting and double-acting vane,what's the difference in the relation between the vane's obliquity in internal slot of rotor and the rotation direction?Why? 4Observe the vanes of the single-acting and double-acting pumps and motors,what's the difference in the relation between the vane's obliquity in internal slot of rotor and the rotation direction?Why? Experiment 3 Experiment of assembling YCY-IB type radial piston pumps 1.General description The oil suction and delivery action of a piston pump depend upon the size change of the chamber produced by reciprocating movement of the pistons within their cylinder bores.For piston pumps,the circular pistons and their corresponding cylinder bores can make high precise match-up and ensure good performance of seal High volumetric and overall efficiencies can be acquired even application under high pressure.The piston pumps can be divided into radial and axial types according to their pistons'arrangements and their different moving directions with respect to the transmission shafts.However,The piston pumps are sensitive to the oil contamination in hydraulic systems and composed of the complex construction.So it is higher costs than other pumps Parameter:Nominal Pressure:32MPa Nominal flow-rate:10~161/min Rated rotational Speed:1000~1500r/min 2.The purpose of the experiment (1)Make a more particular knowledge of the construction features and operating principle of YCY-IB typle radial piston pumps (2)To learn the knowledge of the construction features and operating principle of stroking mechanism of YCY-IB type radial piston pumps 6
附件 24.4 6 2、What kinds of curves does the stator of vane pump consists of ? Why could double-acting vane pumps be used for fixed displacement pumps ? 3、Observe the single-acting and double-acting vane, what’s the difference in the relation between the vane’s obliquity in internal slot of rotor and the rotation direction? Why ? 4、Observe the vanes of the single-acting and double-acting pumps and motors, what’s the difference in the relation between the vane’s obliquity in internal slot of rotor and the rotation direction? Why ? Experiment 3 Experiment of assembling YCY-IB type radial piston pumps 1. General description The oil suction and delivery action of a piston pump depend upon the size change of the chamber produced by reciprocating movement of the pistons within their cylinder bores. For piston pumps, the circular pistons and their corresponding cylinder bores can make high precise match-up and ensure good performance of seal .High volumetric and overall efficiencies can be acquired even application under high pressure. The piston pumps can be divided into radial and axial types according to their pistons’ arrangements and their different moving directions with respect to the transmission shafts. However, The piston pumps are sensitive to the oil contamination in hydraulic systems and composed of the complex construction. So it is higher costs than other pumps. Parameter: Nominal Pressure :32MPa Nominal flow-rate : 10~16l/min Rated rotational Speed : 1000~1500r/min 2. The purpose of the experiment (1) Make a more particular knowledge of the construction features and operating principle of YCY-IB typle radial piston pumps (2) To learn the knowledge of the construction features and operating principle of stroking mechanism of YCY-IB type radial piston pumps
附件24.4 (3)Understand how to regulate the P-Q characteristic curve of YCY-IB typle radial piston pumps (4)List the requirements of the main assembly technology and understand the assembly procedure of YCY-IB typle radial piston pumps 3.Equipment of experimental A YB-type Vane pump for assembly 4.The points for assembly and notes for attention (1)Pay attention to the location of the various parts when the pump is dismantled The parts which have been dismantled should be arranged regularly (2)As the high machining precision the parts of piston pumps is,especially with plunge. oil distribution shaft,servo spool valve,Set Plate,swash plate,the parts which have been dismantled should be arranged regularly and carefully.Surface finishing can not have a friction with a hard object in order to maintain the accuracy of surface roughness of parts. (3)All parts should be assembled as original request when the pump is assembled.Be sure to keep in mind that all parts must not be left out and keep the assembly direction and assembly location of parts correc (4)The parts must be carefully cleaned to ensure that it does not contain any cutting chip and other pollutants before assembling.The washed components which have relative motion should add the appropriate. (5)Must carefully check to make sure if the reciprocating movement of the pistons within their cylinder bores are flexible after the assembly (6)When tightening the Screw,force should be uniform.Note that the order of screw tightening should be symmetrical each other swirling (7)Laboratory report for assembling Vane pumps of YCY-IB type radial piston pumps >
附件 24.4 7 (3) Understand how to regulate the P-Q characteristic curve of YCY-IB typle radial piston pumps (4) List the requirements of the main assembly technology and understand the assembly procedure of YCY-IB typle radial piston pumps 3. Equipment of experimental A YB-type Vane pump for assembly 4. The points for assembly and notes for attention (1) Pay attention to the location of the various parts when the pump is dismantled .The parts which have been dismantled should be arranged regularly (2) As the high machining precision the parts of piston pumps is , especially with plunge、 oil distribution shaft、servo spool valve、Set Plate、swash plate, the parts which have been dismantled should be arranged regularly and carefully. Surface finishing can not have a friction with a hard object in order to maintain the accuracy of surface roughness of parts. (3) All parts should be assembled as original request when the pump is assembled. Be sure to keep in mind that all parts must not be left out and keep the assembly direction and assembly location of parts correct (4) The parts must be carefully cleaned to ensure that it does not contain any cutting chip and other pollutants before assembling .The washed components which have relative motion should add the appropriate hydraulic oil. (5) Must carefully check to make sure if the reciprocating movement of the pistons within their cylinder bores are flexible after the assembly. (6) When tightening the Screw ,force should be uniform. Note that the order of screw tightening should be symmetrical each other swirling (7) Laboratory report for assembling Vane pumps of YCY-IB type radial piston pumps
附件24.4 Experimental date Indoor temperature Major Class Group Name Ad小viso Model Number of experimental device: Substance of laboratory report 1.Description the operating principle of YCY-IB type radial piston pumps and then to explain the structure of the pump and what is the role of the various components. 2.Description the variable characteristic of YCY-IB type radial piston pumps.Do you have understood how to regulate the P-Q characteristic curve of YCY-IB type radial piston pumps: Draw its P-Q characteristic curves and Please specify it. Experiment 4 Performance parameters in hydraulic pump 1.The purpose of the experiment Hydraulic pumps conver mechanical energy into hydraulic energy.They supply fluid to the components in the hydraulic system.Acrossing this experiment,understand the main hydraulic pump performance and test methods and lay the initial foundation for the future design including the selection and the use of hydraulic pump. 2.The experiment contents and experimental program The performance of hydraulic pump experiment Include:the ability to achieve the rated pressure,nominal flow,volumetric efficiency,the value of pressure pulsation (pendulate),Noise,life-span,temperature rising,vibration and so on.The first three are the most important performance We use a single-acting vane hydraulic pump with fixed delivery in this experiment. It's technical indicators(from JB2146-77)is shown at Table 5-1
附件 24.4 8 Experimental date_._._ Indoor temperature_ Major_ Class _ Group_ Name_ Advisor_ Model Number of experimental device: Substance of laboratory report 1. Description the operating principle of YCY-IB type radial piston pumps and then to explain the structure of the pump and what is the role of the various components. 2、Description the variable characteristic of YCY-IB type radial piston pumps. Do you have understood how to regulate the P-Q characteristic curve of YCY-IB type radial piston pumps; Draw its P-Q characteristic curves and Please specify it. Experiment 4 Performance parameters in hydraulic pump 1. The purpose of the experiment Hydraulic pumps conver mechanical energy into hydraulic energy.They supply fluid to the components in the hydraulic system .Acrossing this experiment, understand the main hydraulic pump performance and test methods and lay the initial foundation for the future design including the selection and the use of hydraulic pump. 2. The experiment contents and experimental program The performance of hydraulic pump experiment Include : the ability to achieve the rated pressure, nominal flow, volumetric efficiency, the value of pressure pulsation (pendulate), Noise, life-span, temperature rising, vibration and so on . The first three are the most important performance. We use a single-acting vane hydraulic pump with fixed delivery in this experiment. It’s technical indicators ( from JB2146-77) is shown at Table 5-1
附件24.4 Hydraulic pumps transform mechanical energy (M.n)into hydraulic energy (P.Q)which is transmitted to the actuator of hydraulic system.As a result of the torque loss due to mechanical friction between the components with relative motion(the value expressed by the Mechanical efficiency n.m)and the leakage in the high-pressure chamber(the value expressed by the Volumetric efficiency nv),Output power must be less than input power of the pump.The overall efficiency n is the ratio of the output power P0 to the input power Pi.n=Po /Pi =n m*n v*n h =n m*n v It's more difficult to determine the value of(n.M)directly,so we could generally measure n v and n,and then calculate(n.m) Table 5-1 Project Title rated nominal volumetricoverall Pendulate pressure lisplacemen t effic ciency efficiency kgf/cm2 kgf/cm2 single-acting =80 >=65 vane 16 >=88 >=78 hydraulic 63 25-32 >=90 >=80 pump with 40~125 >=92 >=81 fixed =160 =93 82 delivery 3.Flow-pressure characteristics of hydraulic pump Determine the experimental flow rate of the hydraulic pump under difference pressures and then draw the curve of flow-pressure characteristics Q=f1(P).The leakage in the high-pressure chamber leads to the loss of flow rate.The lower the oil viscosity is,the higher the pressure is and the greater the leakage is.We can read out the value of pressure from pressure meter and read out the value of flow rate from oval wheel flow meter which has the measuring range at 101ml/min or 100ml/min (1)Flow rate without load:if the outlet pressure is beyond zero,the practical flow rate is less than the theoretical flow rate due to the existence of the flow rate leakage,but when the outlet pressure is zero or there is no pressure differential between the inlet and 9
附件 24.4 9 Hydraulic pumps transform mechanical energy (M.n) into hydraulic energy (P.Q)which is transmitted to the actuator of hydraulic system .As a result of the torque loss due to mechanical friction between the components with relative motion ( the value expressed by the Mechanical efficiency η.m)and the leakage in the high-pressure chamber(the value expressed by the Volumetric efficiency ηv), Output power must be less than input power of the pump .The overall efficiency η is the ratio of the output power P0 to the input power Pi , η=Po /Pi =η m *η v *η h =η m *η v It’s more difficult to determine the value of (η. M) directly, so we could generally measure η v and η, and then calculate (η.m) Table 5-1 Project Title rated pressure kgf/cm 2 nominal displacement volumetric efficiency % ml/r overall efficiency % Pendulate kgf/cm 2 =80 >=65 16 >=88 >=78 25~32 >=90 >=80 40~125 >=92 >=81 single-acting vane hydraulic pump with fixed delivery 63 >=160 >=93 >=82 ±2 3. Flow –pressure characteristics of hydraulic pump Determine the experimental flow rate of the hydraulic pump under difference pressures and then draw the curve of flow –pressure characteristics Q = f 1 (P).The leakage in the high-pressure chamber leads to the loss of flow rate. The lower the oil viscosity is, the higher the pressure is and the greater the leakage is. We can read out the value of pressure from pressure meter and read out the value of flow rate from oval wheel flow meter which has the measuring range at 101ml/min or 100ml/min. (1)Flow rate without load: if the outlet pressure is beyond zero, the practical flow rate is less than the theoretical flow rate due to the existence of the flow rate leakage, but when the outlet pressure is zero or there is no pressure differential between the inlet and
附件24.4 outlet pressure,the pump leakage is zero.The flow rate under this condition is considered equal to the theoretical flow rate in industrial production.We should determine the Flow rate without load of pump under the condition that cross-sectional area of Throttle 10 is the largest (2)Rated flow rate:the flow rate which permits operation continuously under the rated pressure and the rated rotating speed. (3)Practical flow rate Q on the condition of different pressure;the different pressure is determined by the throttle.Read out the flow rate Q under the corresponding pressure. 4.Volumetric efficiency nv If the motor's rotational Speed in the hydraulic pump at zero pressure is basically the same as the rotational Speed in the rated working pressure (the value of rated rotational Speed and rotational Speed without load is equal),n=Q1/Q2 5.Overall efficiency of hydraulic pump n n=No/Ni or No=Ni*n=Ni*nm*nv The input power of hydraulic pump Ni Ni=M*N/974(kw) M-input torque on the condition of rated pressure n-rotational Speed of hydraulic pump on the condition of rated pressure The output power of hydraulic pump No No=P*Q/612(KW) P-The output pressure of hydraulic pump on the condition of rated pressure Q-The flow rate of hydraulic pump on the condition of rated pressure The overall efficiency of the hydraulic pump can be expressed as follows:
附件 24.4 10 outlet pressure, the pump leakage is zero .The flow rate under this condition is considered equal to the theoretical flow rate in industrial production. We should determine the Flow rate without load of pump under the condition that cross-sectional area of Throttle 10 is the largest. (2)Rated flow rate: the flow rate which permits operation continuously under the rated pressure and the rated rotating speed. (3)Practical flow rate Q on the condition of different pressure; the different pressure is determined by the throttle. Read out the flow rate Q under the corresponding pressure. 4. Volumetric efficiency ηv If the motor’s rotational Speed in the hydraulic pump at zero pressure is basically the same as the rotational Speed in the rated working pressure (the value of rated rotational Speed and rotational Speed without load is equal), η=Q1/Q2 5. Overall efficiency of hydraulic pump η η=No/Ni or No=Ni*η=Ni*ηm*ηv The input power of hydraulic pump Ni Ni=M*N/974(kw) M-input torque on the condition of rated pressure n- rotational Speed of hydraulic pump on the condition of rated pressure The output power of hydraulic pump No No=P*Q/612(KW) P-The output pressure of hydraulic pump on the condition of rated pressure Q- The flow rate of hydraulic pump on the condition of rated pressure The overall efficiency of the hydraulic pump can be expressed as follows: