Servo-Controlled Endurance Testing Machine For Rubber Pads and
Silent Blocks (Capacity-300kN)
HEICO Cyclic/Static Rubber pad testing machines are state of the art machines based on
Servo Controlled Closed Loop system. All the controls and data acquisition is through the
computer. The system has a wave generator, cyclic & static, which forms a base to the
compound signal. This signal is sent to PID controller. The machine response signal
through base sensors that is displacement/load is also passed on to the PID controller.
The difference in two signals actuates the torque motor of the servo valve thereby
ensuring that the machine system follows the set path of the wave generator. Dwell time
loading –unloading and recording of the reading is controlled through the software
supplied as standard along with the system.
The machine is capable of conducting following tests on Elastomeric Pad and Silent
BlocksFOR ELASTOMERIC PAD TESTING
1. Compressive Load Deflection Characteristic Test (As Per Clause 3.4.3 of RDSO
Specifications)
Test Condition: - The system loads the pad from 0-20Tons three times at Strain
rate of 10+5 mm/min. and then in the 4th cycle, it records Load versus
Deformation Characteristics. Deflection characteristics are recorded and printed at
Loads of 10, 15 and 20Tons.
2. Shear Load Deflection Test (As Per Clause 3.4.4 of RDSO Specifications)
Test Condition: - Refer to RDSO sketch No.WD2-7561-Ss/1, the system Loads
the pad 3 times from 0-12Tonnes with the Strain rate of 10+ 5mm/min. and in the
4th cycle holds the load at 12Tonnes. Then Horizontal Load of 5Tonnes is given at
a Strain rate of 10+ 5mm/min. 3 times successively and in the 4th cycle records
Load versus Deflection characteristics.
3. Shear Fatigue Test (As Per Clause 3.4.6 of RDSO Specifications)
Test Condition: - Sample is fixed at 10 degrees to the horizontal as per Drawing
No.WDX-91/7Alt.1 and then loaded from 7-22Tonnes at a frequency of 2Hz for
5,00,000cycles. The system automatically adjusts any permanent deformation and
keeps the load within the specified limits of 7-22Tonnes.
FOR SILENT BLOCK TESTING AS PER RDSO SPEC. NO. RDSO/2007/CG-06
1. Compression Test- Applying a Load of 15Tons for three successive cycles and
record the deformation in the fourth cycle.
2. Torsion Test- The inner shaft of sample is clamped in the fixture and apply a
rotating load on outer body for three successive cycles up to 8° and record the
data at every 0.5° in the fourth cycle.
3. Endurance/Fatigue Test- Apply a load of 5Tons-15Tons at a maximum
frequency of 1-2Hz with a maximum deflection of 3mm for 2,50,000 cycles or
more.
FOR SILENT BLOCK TESTING AS PER RDSO SPEC. NO. RDSO/2006/CG-15
1. Compression Test- Applying a Load of 8Tons for three successive cycles and
record the deformation in the fourth cycle.
2. Torsion Test- The inner shaft of sample is clamped in the fixture and apply a
rotating load on outer body for three successive cycles up to 8° and record the
data at every 0.5° in the fourth cycle.
3. Conical Test- The inner shaft of sample is clamped in the fixture and apply a
conical load on outer body for three successive cycles up to 8° and record the data
at every 0.5° in the fourth cycle.
NOTE- The fixtures to conduct different test on Elastomeric Pad and Silent blocks
are not part of the base machine and are quoted separately.
A typical test set up comprises of
1. Load Frame with side jacks including
a) Hydraulic Actuator (+/-300kN)
b) Load Cell (+/-500kN)
c) Displacement Transducer (+/-100mm/200mm)
2. Hydraulic Power Pack with Electrical Control Cabinet
3. Module with servo valve, high pressure filter, gas filled accumulators
4. Recording System includes
a) Signal Conditioning and Controlling Unit
b) Computer for Controlling and Data acquisition
c) Control and Analysis Software
The description of the different parts of the machine is given below1. LOADING FRAME WITH HYDRAULIC LIFT
Loading units is free standing units. It has a base and a cross head with fitted actuator
along with servo valve. Cross head moves along the two pillars. Two hydraulic rams are
provided for lifting of the cross head. Hydraulic locks are provided to lock the cross head
at any position to suit the sample height. Controls are provided for lifting and lowering of
the middle crosshead. Arrangement is also provided for locking of the crosshead at any
desired position. Base of the frame will have T-slots to place the fixtures for different
rubber components. Manifold is provided at the base for proper distribution of oil to the
actuator and hydraulic-lock. An operator control panel is fixed on the frame for HPS
ON/Off, Emergency stop, switch for movement of the cross head etc.
Technical SpecificationsCapacity
:
Horizontal Clearance
:
Vertical Clearance
:
Vertical Cross Head Adjustment
:
Capacity of the Actuator
:
Displacement (Testing stroke length) :
300kN
450mm
400mm
200-400mm
300kN
0-200mm (± 100mm)
a) Actuator with Servo valve
Actuator is a linear motion device, which gives a controlled motion either on stress basis
or strain basis. It is a precision piece of equipment which follows the command from the
wave generator through the servo valve. It is an equal area ram and piston with surface
finish of 0.2 microns. End plates have metallic seals for side thrust. Servo valve is fixed
to the actuator .These valves are high performance two stage valves with a pressure drop
of @ 70 bars.
Technical SpecificationsType
Load carrying capacity
Effective area
Stroke length
Operating Pressure
Servo valve 2 stage
In built Displacement sensor
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:
:
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Double Acting & Double Ended
300kN
170Sqcm
200mm
180Bars
45 LPM
200mm (+/- 100mm) * 0.01mm)
a. Load Cell
It is a strain gauge based type load cell with full wheat-stone bridge configuration. It has
Alloy steel, electro less nickel plated structure for outstanding corrosion resistance.
Structure of the load cell is such that it can be loaded in compression over few million
numbers of times. It has a over load capacity of 150% with a resolution of 0.01kN.
Technical Specifications
Capacity
Make
Full Scale Output
Non-Linearity
Hysteresis
Non-Repeatability
Creep (30 minutes)
Excitation Voltage
Safe overload
Operating Temperature
Protection Class
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:
:
:
500kN
Adi-Artech
2.0 mV/V
< + 0.05% FSO
< + 0.05% FSO
< + 0.05% FSO
< + 0.03% FSO
10 Volts DC
150%
0O C to +60 O C
IP68
c) Displacement Transducer
The variation in strain, deflection etc is measured with help of Micropulse Linear
Transducer. Salient feature of Micropulse Transducer:
- Very high resolution, repeatability and linearity.
- Immunity to shock, vibration, contamination and electrical noise.
- An absolute output signal.
- Automatic signal regulation.
- 2 kHz update rate
- Resolution 0.01mm
Technical Specifications
Range
Make
Full Scale Output
Independent Linearity
Repeatability
Hysteresis
Excitation Voltage
Sampling Time
Operating Temperature
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200mm
Gefran
10.0 Volts
+ 0.02% of FS
<0.01mm
<0.01mm
24 Volts DC
1ms
-30O to +75 O C
Protection Class
:
IP67
2. HYDRAULIC POWER PACK
Hydraulic power supplies are compact in design and are suitable for the supply of
required flow and pressure for the actuation of the actuator. It has a oil tank of adequate
capacity, vane type pump powered by a three phase motor. All the electrical controls
including the temperature controller are fixed on one side of the tank. It includes all the
accessories like pressure line filter, return line filter, oil level, relief valve, pressure gauge
and shell & tube type heat exchanger. Anti vibration mountings are provided as standard
along with the HPS.
Technical SpecificationsFlow of the pump
Operating Pressure
Type of pump
Capacity of the oil tank
Power rating of the motor
Heat exchanger capacity
Pressure line filter
Return line filter
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53lpm
180 bars
Vane
200litres
25HP
18,000 kcal/hr
3 microns
10 microns
All accessories like, pump pressure gauge, level gauge, pressure-line filter (3 microns) ,
return line filter (10 Microns) , digital temperature controller are provided as standard
along with the system.
System will be supplied with necessary cable and fittings for the operation of the
machine. Total machine operates on 440VAC 3 phase supply.
NOTE1. Water supply at the rate of 100 LPM @ 30-35°C is to be provided by the consignee.
2. Power connection equivalent to 400 + 10% VAC, 50 Hz, 3Phase, 60 Amp and single
phase 220VAC, 15Amp, 50Hz is to be provided by the consignee.
ELECTRICAL CONTROL CABINET
This Electrical control Cabinet consisting of Electrical Components like:(1)
Contactors.
(2)
Time delay relays.
(3)
Power inlet.
(4)
Indicating lamps(RYB)
(5)
Temperature Controller
and other electrical accessories are fixed inside the Electrical Control cabinet.
3. RECORDING SYSTEM
Recording system provides the digital servo control, Ramp generation, different
waveforms (Sine, Square & Triangular) for the machine, data acquisition, hydraulic
control etc. for the continuous operation of the system.
(a) Signal Conditioning & Controlling Unit
HEICO servo controller basically consists of signal conditioning and controlling unit.
Signal conditioning unit receives the output signal from the various transducers (Load
cells and Displacement Transducers) and amplifies and process that signal as per the
requirement and transfer it to computer through connecting cables where it is accepted by
the data acquisition system. The out put from the signal conditioning unit for each
transducers ranges from 0-5V. The controlling unit controls the operation of the machine
either on Load basis or Displacement basis.
It consists of dedicated servo-controller card that gives the desired processed signal
through the P.I.D controller to the servo valve to operate either in strain mode or stress
mode. It also sends the signal to computer and accepts the command from the software to
operate in desired manner. The parameters like rate of loading for machine, safety limits
for load & displacement can initially be programmed through the software. The
programming facility is given to operate the system in STATIC MODE from
0.01mm/Sec -1mm/Sec in displacement control mode or 0.1kN/sec-5kN/sec in load
control mode. In DYNAMIC MODE the cycling can be done at a frequency from
0.1Hz-5Hz.
(Note: - With the increase in frequency the amplitude (stroke) tend to decrease.
Therefore, Performance curve is attached for ready reference)
Specifications of Controller
• Auto PID operation with auto loop shaping servo operation
• Closed loop update rate is 10 kHz
• No. of control channels- 2
• Demand generation - Sine, Triangular, Square, Random wave forms and Ramp signal
• Standalone operation to Start, Stop & Hold the test system
• High speed Data Acquisition card with 100 kHz sampling rate and 16-bit resolution
acquires data from the signal conditioning and controlling unit
• System accuracy- Load accuracy : + 0.5% of Indicated Load
Displacement accuracy: + 0.5% of Indicated Value
• Two types of Loading- Dynamic (for fatigue test) and Static (Ramp)
• Dynamic Frequency Range- 0.1Hz to 5Hz (Note: The stroke of actuator depends
upon the frequency of operation)
• Static Ramp rate: Load control mode - 0.1kN/sec to 5kN/sec.
Displacement control mode- 0.01mm/sec to 1mm/sec.
• Environmental Temperature- 0O C to +60 O C
• Relative Humidity- 10% to 85% non-condensing
• Supply Input- 220-240 VAC, 50 Hz
b) Computer for Controlling and Data acquisition
System is provided with dedicated computer of following configuration with built in data
acquisition card.
Computer
Intel i5 processor,
500 GB HDD, 4GB RAM, DVD R/W drive,
Key Board, Optical Mouse, 6USB Ports
19” LCD Monitor,
HP Deskjet Printer, UPS
(Note- Latest available model of the computer will be supplied at the time of
delivery)
c) CONTROL AND ANALYSIS SOFTWARE
Control software is the integral part of the system for precise controlling & Data
Acquisition and analysis.
Salient Features
• Windows Xp based user friendly software
• Four different types of loading can be given to the sample- Sine, Triangular,
Square, Random waveform and Ramp signal
• In Cyclic mode machine can go as high as 10 Hz (10 cycle/second) and as low as
0.1 Hz (0.1 cycle/second) covering.
• Programmable Loading parameters – Frequency, Base, Amplitude, velocity etc.
• Programmable rate of loading in static mode
• Two types of Tests- Dynamic (for fatigue test) and Static (Ramp).
• Defining test profiles and number of cycles
• Computer/Software programmable Safety Limits for each load & displacement
• Independent Taring of each channel
• Facility to hold the actuator and restart the loading during the test.
• Facility to increase the Base load, frequency and amplitude during the test
• Facility to save the data after the test
• Shows number of cycle on screen
• Store the number of cycles in Dynamic test
• On-line display of Load v/s Time, Displacement v/s Time and Load v/s
Displacement graphs.
• On-line display of Load, Displacement readings
• Auto adjustment of graph scales
• Storing of data of each channel in user defined file/directory that can be directly
opened in Excel and Analysis Software
• To analyze the test result Analysis software is given which shows different type
of graph and data i.e. Load v/s Displacement graph, Load v/s Time graph, and
Displacement v/s Time graph for statistical analysis.
Analysis Software
Analysis software provides flexibility to user to do statistical analysis of test results
and report generation.
Salient features
• Plotting of following graphsa) Load v/s Time
b) Displacement v/s Time
c) Load v/s Displacement
• Generation of various test results (Number of cycle, Maximum and minimum
Load value, Deflection at various loads etc.)
• Statistical analysis of the test results
• Detailed Summary Report
• Facility to take print out of the data and all the graphs
• Result Sheet generation
NOTE- ONE ADDITIONAL LOAD CELL OF 2TON CAPACITY WILL BE
PROVIDED FOR CONDUCTING TORSIONAL AND CONICAL TESTS
OPTIONAL ATTACHMENTS AT EXTRA COST
1. Attachment for Shear Load Deflection Test
It is suitable to conduct tests on the Elastomeric Pad as Clause
3.4.4 of RDSO specification. It consists of a frame with
horizontal actuator fitted with one Load cell of 5Ton capacity
and one Displacement sensor of + 50mm range. It is a geared
motor arrangement having a total travel of 100 mm. The rate
of strain is fixed at 10mm/min.
2. Attachment for Shear Fatigue Test
It is suitable to conduct tests on the Elastomeric Pad as Clause
3.4.4 of RDSO specification. It is specifically designed to
place the pad in such a way that load is applied at angle of 10º
between 7-22Tonnes at a frequency of 2Hz.
3. Fixture with ‘U’ blocks for Compression
and Endurance Test on Silent Block
-
1No.
4. Clamping Fixture for Torsion Test on Large Silent Block
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1No.
5. Fixture with ‘U’ blocks for Compression on Small Silent Block
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1No.
6. Clamping Fixture for Torsion Test on Small Silent Block
-
1No.
7. Clamping Fixture for Conical Test on Small Silent Block
-
1No.
For further details, contact manufacturers & exporters
HYDRAULIC & ENGINEERING INSTRUMENTS
(An ISO 9001:2008 company)
A-13, Naraina Industrial Area, Phase-II, New Delhi-110 028, INDIA
Tel: 0091 11 2589 3820/21/22/23, Fax: 0091 11 2589 3152
E-mail : info@heicoin.com
Web: www.heicoin.com
Assured after sale service all over India