The FORCE TECHNO ENGINEERS Spring Testing Machine, Models St and CST, incorporates design features to enable high accuracy testing with economy, speed and versatility
- Loading Accuracy as high as + 1%
- Four standard measuring ranges available with auto load-selector.
- Deflection is read directly on electronic Electronic Digital Display.
- Straining at variable speeds to suit a wide range of applications.
- Autographic recorder supplied as standard to enable study of behavior of springs
- Motorised drive for rapid adjustment of the height
- High reading accuracy due to large size of dial.
- Large effective test space enables testing of wide range of springs.
- Robust staining frame of an extremely rigid construction.
- Safe operation ensured be means of safety devices.
- Fully enclosed and protected pendulum.
FORCE TECHNO ENGINEERS Laminated Spring Testing Machine is designed to test Laminated Springs and Coil Springs under compression and bending loads.
Principal of Operation :
Operation of the machines is by hydraulic transmission of load from the test specimen to a separately housed load indicator. The hydraulic system is ideal since it replaces transmission of load through levers and knife edges, which are prone to wear and damage due to shock on rupture of test pieces.Load is applied by a hydrostatically lubricated ram. Main cylinder pressure is transmitted to the cylinder of the pendulum dynamometer system housed in the control panel. The cylinder of the dynamometer is also of self-lubricating design. The load transmitted to the cylinder of the dynamometer is transferred through a lever system to a pendulum. Displacement of the pendulum actuates the rack and pinion mechanism which operates the load indicator pointer and the autographic recorder. The deflection of the pendulum represent the absolute load applied on the test specimen.Return movement of the pendulum is effectively damped to absorb energy in the event of sudden breakage of a specimen.
Machine consists of :
This consists of a “C” type rigid frame with hydraulic cylinder at its top and adjustable main testing tale is connected to an upper cross-head through two screwed columns can be rapidly adjusted to test height by means of motor. A pair of trolleys is provided on the table to take the horizontal deflection of the spring under loading.Laminated springs are tested by placing them on trolleys provided on the table. Coil Springs are tested by placing them between the compression plates. Hardness test can also be conducted with a suitable attachment.
Control Panel :
The control Panel consists of a power pack complete with drive motor and an oil tank, control valve a pendulum dynamometer a load and deflection indicating system and an autographic recorder.
Power Pack :
The power pack generates the maximum pressure of 200 kgf/cm2 the hydraulic pump provides continuously non-pulsating oil flow. Hence the load application is very smooth.
Hydraulic Controls :
Hand operated wheels are used to control the flow to and from the hydraulic cylinder. The regulation in the oil is infinitely variable. Incorporated in the hydraulic system is a regulating valve which maintains a practically constant rate of table movement.
Load and Deflection Indicator System :
The load Indicator System consists of a large dial and a pointer. A dummy pointer is provided to register the maximum load reached during the test. Different measuring ranges can be selected by operating the range selection knob. An overload trip switch is incorporated which automatically cuts out the pump motor when the load range in use is exceeded.
The deflection indicator system operates electronically and deflection is read directly on the digital display with least count of 0.1 mm. The encoder is mechanically coupled to the main hydraulic ram for getting signal of deflection.
Pendulum Dynamometer :
This unit permits selection of favorable hydraulic ratios producing relatively small frictional forces. Pressurised oil in the loading cylinder pushes up the measuring piston proportionately and actuates the special dynamometer system. The piston is constantly rotated to eliminate friction. The dynamometer system is also provided with special damper and ensures high reliability of operation. The load transmitted to the dynamometer is transferred through a pendulum to the load indicator.
Autographic Elongation Recorder :
This unit is of the pen and drum type and is supplied as standard. The horizontal motion of the pen produces the load ordinate of the diagram and the drum rotation produces the extension ordinates in the ratio of either 1:1 or 1:2.
Accuracy & Calibration :
AII FORCE TECHNO ENGINEERS Laminated Spring Testing Machines are closely controlled for sensitivity, accuracy and calibration during every stage of manufacture. Every machine is then calibrated over each of its measuring ranges in accordance with the procedure laid down in BS : 1610 : 1964
FORCE TECHNO ENGINEERS Spring Testing Machines comply with Grade “A” of BS : 1610 : 1964 and Grade 1.0 of
IS 1828 : 1975 An accuracy of + 1.0% is guaranteed from 20% of the load range selected
to full load.
Helical Coil Spring Testing Machine Model CST :
FORCE TECHNO ENGINEERS ‘s range also includes Helical Coil Spring Testing Machine, Model CST for testing coil springs under compression loads. the principle of operation, details on control panel, except deflection indicator system, accuracy and calibration are the same as the laminated Spring Testing Machine. Model ST described alongside. The straining unit is designed for coil Springs. It consists of a Hydraulic Cylinder and a table coupled with the ram of the hydraulic cylinder mounted on a robust base. The cylinder and the ram are individually lapped to eliminated friction. The cross-head is connected to two screwed columns and is driven by a motor for rapid adjustment of test height.
|Maximum capacity (Tone)||6||10||10||10||50|
|1st Measuring Range (Tone)||0-6||0-10||0-10||0-20||0-50|
|Minimum Graduations (kgf)||10||20||20||40||100|
|2nd Measuring Range (Tone)||0-3||0-5||0-5||0-10||0-25|
|Minimum Graduations (kgf)||5||10||10||20||50|
|3rd Measuring Range (Tone)||0-18||01-2.5||01-2.5||0-4||010|
|Minimum Graduations (kgf)||3||5||5||8||20|
|Table size (mm)||—||—||250 x 2400||400 x 2400||460 x 2650|
|Vertical travel of table for Model ST/of Crosshead for Model CST (mm)||150-1250||150-1250||0-400||0-500||0-600|
|Distance between trolleys
|—||—||500 – 2150||650 – 2150||850-2300|
|Pair of compression plates adjustable (mm)||360||360||250||400||460|
|Maximum distance between compression plates (mm)||1250||1250||400||650||750|
|Range for measurement of deflection range (mm)||0-250||0-250||0-300||0-250||0-300|
|Minimum graduation of deflection range||0.5||0.5||0.5||0.5||0.5|
|Ram stroke (mm)||200||200||300||250||300|
|Straining/piston speeds (mm/min)
(at no load)
|Clearance between columns (mm)||500||500||—||—||—|
It is recommended that machines be erected on a foundation. Details on foundation can be given on request