Manual Book: BLO 80 2.
Characteristics In most respects aerostatic bearings are ideally suited for use in high-speed machines. Their low friction provides high mechanical efficiency and minimizes bearing heating problems. They are quiet and smooth running and do not add to sound and vibration levels of the machine in the way that high-speed ball bearing do. Applications One of the most important fields of application of aerostatic bearings is undoubtedly on machine tools where the range of machine tool application is very wide.
CONTENTS 1. Fundamental Safety Instructions. 2. Warranty notice. 3. Attention – Daily Check Before starting the spindle 4. System general description. 5. Aerostatic Spindle Label. 6. Installing the spindle. 7. Removing the spindle from the machine. 8. Specification for High – Speed Air Spindle. 9. Electrical Motor Specification. 10. Brushless DC Motor 11. Diagrams: a) Torque & Power Vs. Rotation Speed b) Final Velocity Vs. Torque & Acceleration Time & External Inertia c) Radial Stiffness Vs. Air Pressure.
FUNDAMENTAL SAFETY INSTRUCTIONS 1. Basic operation and designated use of the machine. 1.1 1.2 1.3 2. Organizational measures. 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 2.11 2.12 2.13 2.14 2.15 2.16 2.17 3. The machine has been built in accordance with state of the art standards and recognized safety rules. Nevertheless, its use may constitute a risk to life and limb of the user and of the third parties, or cause damage to the machine and to other material property.
3.5 Do not allow persons to be trained or instructed or persons taking part in a general training course to work on or with the machine without being permanently supervised by an experienced person. Work on the electrical system and equipment of the machine must be carried out only by a skilled electrician or by instructed person under the supervision and guidance of a skilled electrician and in accordance with electrical engineering rules and regulations. 3.6 4.
6.2 6.3 6.4 6.5 6.6 6.7 6.8 Work on the electrical system or equipment may only be carried out by a skilled electrician himself or by specially instructed personnel under the control and supervision of such electrician and in accordance with the applicable electrical engineering rules. If provided for in the regulations, the power supply to parts of machine, on which inspection, maintenance and repair work has to be carried out, must be cut off.
ATTENTION DAILY CHECK BEFORE OPERATING THE SPINDLE 1. For first time installation, look at “Installing the spindle” paragraph. 2. Check air supply (5-6 bar.) 3. Check ventilation exits. 4. Check for free movement of the shaft. 5. The spindle must be securely clamped to the machine and clear from any distraction. 6. Check for electric connections and command (community grounding). 7. Start the spindle.
SYSTEM GENERAL DESCRIPTION TOP VIEW SIDE VIEW 7
INSTALLING THE SPINDLE 1. Remove the spindle from its package. 2. Follow the machine’s safety and installation instructions. 3. Clamp the spindle to the machine - using 4 screws (M5 - minimal length 15 mm). Note: Locate the spindle on the position pins; 4. 5. 6. 7. Remove plugs from air connections (2). Connect inlet air pipe Ø6 mm to “AIR IN” (AI). Connect outlet air pipe Ø6 mm to “AIR OUT” (AO) or you may use a silencer. Remove black plastic nut from the end of the shaft. 8.
REMOVING THE SPINDLE FROM THE MACHINE Note: Always lift the spindle from the body and not from the shaft. 1. Turn off the spindle. Make sure the shaft has stopped before continuing. 2. Follow the machine’s safety and installation instructions. 3. Disconnect power cable. 4. Disconnect signal cable. 5. Turn off air supply. 6. Disconnect air pipes from the spindle. 7. Remove wheel D-400 (ø65 mm). 8. Remove wheel D-1400 (ø76 mm). 9. Close AO and AI holes with plastic plugs x2. 10.
SPECIFICATION FOR HIGH-SPEED AIR SPINDLE Rotation speed – 2K ~ 75K [rpm] Air supply Pressure Flow rate Filtering Dew point Oil residue Static run-out of the rotor Radial direct. (max) Thrust direct (max) Dynamic run-out of the rotor Radial direct(max) Thrust direct. (max) Radial direct. Fluctuation between peaks Thrust direct. Fluctuation between peaks Rigidity of the rotor Radial direct. Thrust direct. Load capacity Radial direct. Thrust direct.
ELECTRICAL MOTOR SPECIFICATION Size Constants: • • • • • • • • • • • • • • • • • • • • • • • • • • Maximum Rated Torque Maximum Continuous Stall Torque @ Temp. Rise 100 [ºC] Motor Constant Electrical Time Constant Mechanical Time Constant Angular Acceleration (theoretical) Thermal Resistance Maximum Cogging Torque Viscous Damping Hysteresis Drag Torque Rotor Inertia Frameless No.
BRUSHLESS DC MOTOR Maximum Continuous Stall Torque (TC) is the amount of torque produce at zero speed, which results in a 100 Cº rise in temperature. Generally the highest operation temperature that should be allowed is 150 Cº and is a combination of the ambient temperature and the temperature rise for a given operating condition. Maximum rated Torque (TR) is the amount of torque that the motor can produce without demagnetizing the rotor. The torque is only available for short durations.
Torque & Power Vs. Rotation Speed 1600 T [Nm] 0.3 Pw [w] 0.25 1200 Nominal Power 0.2 0.15 800 0.1 400 0.05 0 0 0 20 40 60 0 80 Vsp [Krpm] Vsp [Krpm] - Rotation Speed T [Nm ] - Spindle Torque Pw [w ] - Power 20 40 60 80 Vsp [krpm] Conditions 1. Temp Rise less then 100° C. 2. Continuous operation at a load point. 3. The curves assume a 25°C ambient environment. 4. No external loads. Continuous Duty Speed/Torque Curves for 100°C Temperature Rise.
Ps[bar] 20 Radial Stiffness Vs. Air Pressure Sr[N/m] Sa [N/ µ ] Sr [N/ µ ] 2 1.5 Sr=[13.642*ln(Ps)-7.956] \ 2 2.5 4.544 3 7.031 Theoretical curves 3.5 9.134 Ps [bar] - Spindle air pressure. 4 10.956 Sr [N/ µ ] - Radial Stiffness. 4.5 12.563 5 14 CONDITION 0 1 2 3 4 5 6 7 8 5.5 15.3 1. No Rotation. Ps [bar] 6 16.487 6.5 17.579 Axial Stiffness Vs. Air Pressure 18.59 15 7 Ps[bar] Sa[N/m] Sa=6.425*ln(Ps)-1.454 3 10 2 2.5 4.434 Theoretical curves 5 3 5.605 Ps [bar] - Spindle air pressure. 3.5 6.
Vsp[Krpm] Vf[Volt] 5 9.27 Vf [Volt] 150 10 120 15 90 20 60 25 30 30 350 18.54 27.81 37.08 46.35 55.62 64.89 74.16 20 10 83.43 92.7 101.97 111.24 40 0 45 50 55 60 3 2.5 65 If [Amp] Vf = 1.854*Vsp Vsp [Krpm] - Rotation Speed Vf [Volt] - Voltage between two phases. 30 40 50 60 70 Vsp [Krpm] Current Vs. Rotation Speed 120.51 70 2 If = 0.159*e 129.78 51.5 10 1 0.5 15 20 0 25 0 30 35 40 45 1.5 50 0.194 0.237 0.289 0.353 0.432 20 10 0.528 0.645 0.788 0.962 1.
Raw Materials Data The Spindle is mayd from the following materials: Stainless steel: SAE 303, SAE 2316. Brass SAE 40, Copper. Polymers: Delerin Chemical composition SAE 303 %C %Si %MN %P %S %CR %MO %Ni 0.15 1 2 0.2 0.15-0.4 17-19 0.6 8--10 SAE 2316 %C %Si %MN %P %S %CR %MO %Ni 0.34 0.16 0.88 0.025 0.003 15.12 0.91 0.53 BRASS SAE 40 %Cu %Pb %Al %Fe %Ni %Sn COPPER Cu 58.1 2.83 0.01 0.29 0.1 0.24 %Cu %Pb %Bi 99.96 0-8 0-1 Mechanical properties Hardness HB 0.2% proof stress N/mm2 0.
SPINDLE MODES 0 10 20 30 40 50 60 70 80 Length[mm] 90 100 110 120 130 140 150 160 170 180 190 200 210 220 1.25 1 0.75 1 2 3 4 0.5 0.25 0 5 -0.25 6 -0.5 -0.75 -1 -1.
SPINDLE BALANCING Why is balancing important? Force (F) generated by unbalance can be calculated from formula: F(Kg)= 0 . 001 x(gmm)x(RPM/ 1000 ) 2 2 F(Kg)= 0 . 001 x(w x r)x(RPM/ 1000 ) r where w = Unbalance weight in grams r = Radius in millimetres Effects of Unbalance Reduced component life. Bearings, seals, windings, rotor bars, foundations, supports. Impaired clearancs / tolerances. Component displacement, Reactive misalighment. Resonance. Flexing of critical speed rotors.
Rigid Rotors Maximum operating speed below 70% of natural frequency or first critical speed. Can be balanced at any speed: Will remain in balance throughout speed range provided tolerance, calculated to maximum service speed, is achieved. tolerance, calculated to maximum service speed, is achieved. Balance corrections made in any two arbitrary correction planes.
ISO Rotor Classifications GO.4 Spindles, precision grinders, Gyroscopes. G1 Small special purpose electrical rotors / drives. G2.5 Gas / steam turbines, Turbo compressors, machine tool drives. Small and special purpose electric rotors. G6.3 Fans, Pump impellers, general electric rotos, centrifuge drums, general machinery parts. Balance Tolerances ISO 1940 / 1 MCD (e µ m) = G x 1000 = 9549 x G 2 π n/ 60 n Where: G - Balance quality grade n - Max rotor seryice speed Uper (gmm) = e per.
Applying ISO 1940 on Aerostatics Spindle @ G0.4 MCD (e) C of G Service speed: 80000 rpm Weight: 700 grams Balance quality: G0.4 MCD (e) µ m = 9549 G/n MCD (e) µ m = 9549 x 0.4/80000 = 0 . 048 µ m So Permissible Unbalance (U per ) = 0.048 µm x 0.7 kg So Permissible Unbalance (U per ) = 0 . 034 gmm TOTAL Permissible Unbalance ( Uper ) at C of G = 0 . 034 gmm TOTAL For Symmetrical Rotor = 0 .
ELECTRICAL SYSTEM CONNECTOR (RM215TR-10SC) Connector would be: RM215TR-10SC MOTOR FUNCTION WIRE COLOR PIN Motor A Motor B Motor C VS Hall Effect 1 Hall Effect 2 Hall Effect 3 Ground Thermistor Thermistor Red White Black Blue Brown Orange Yellow Green Violet Violet 1 2 3 4 5 6 7 8 9 10 22
THERMISTOR “Thermistor” is the generic name given to thermally sensitive resistors. Negative temperature coefficient thermistor is generally called as thermistor. Thermistor is a semi conducting ceramic resistor produced by sintering the materials at high temperature and made mainly from metal oxide. Depending on the manufacturing method and the structure, there are many shapes and characteristics for various purposes such as temperature measurement, temperature compensation etc.
Description of a Spindle Testing. Introduction: After connecting the spindle to the computerized testing system (air, electricity, control etc.), it will automatically perform a series of tests, record the results, send notice when the test fails and stop in case of a danger. At the end of each test a detailed report is received including diagrams. • The operator can change the numeric definitions for the operating process. • Results recording will be continuous and written in data format.
COOLING WATER SEALING & FLOW TEST CIRCUIT C electric valve water inle t E air flow meter F pressure meter SPINDLE in shuttle valve D electric valve water outlet out air inlet air outlet A electric valve B electric valve FLOW TEST CIRCUIT L main pressure H manual pressure regulator I spindle air pressure G electric valve J inlet air flow K outlet air flow SPINDLE AIR IN AIR OUT air outlet inlet 25
FAILURE – CAUSE - PREVENTION Cause Prevention Failure The shaft doesn’t rotate freely.
