Application:-

Universal Testing Machines have a wide range of applications. A number of materials and metals in different forms and shapes can be tested for a variety of tests like Tension, Compression, Transverse, Bend, Shear, Brinell Hardness, etc.

Special attachments are also available for testing of flat belts, chain links, wire ropes, etc.

Construction:-

Loading frame
The base has a hydraulic cylinder at its center, and two main screws at both ends. The middle cross head is mounted on screws through main nuts. The middle cross head can be moved up or down through chain transmission and geared motor to adjust the initial tensile/compression clearance. On the piston rests an assembly of upper, lower crosshead and two columns. The individually lapped cylinder piston assembly ensure smooth transfer of force with minimum friction.

Hydraulic system
Hydraulic circuit consists of hydraulic power pack having a directly driven radial plunger pump which gives a continuous non pulsating flow of oil pressure upto 250 bar. Oil filter, Oil strainer, Air breather, Oil level Indicator, Drain plug are provided on the power pack. A pressure compensated needle type flow control valve, is provided to control the oil flow to cylinder thereby achieving desired piston speed. Infinitely variable speeds can be obtained with the help of valves.

Electrical system
A separate switch box and electrical panels are provided. Both the hydraulic pump motor and the geared motor have interlocks. Limit switches are provided to stop the hydraulic pump motor if the load increases beyond the machine capacity or if the piston stroke is exceeded.

Computerised  Control Panal :-

Load measuring system
The oil pressure in the main cylinder is also transferred to an electronic pressure transducer which gives a proportionate signal to the Data Acquisition Unit. Both, the motor for hydraulic operation and cross head motion, are controlled by push buttons and they have interlocks to prevent simultaneous working of the Rotary Encoder.
Encoder signal is fed to the Data Acquisition Panel to get displacement in mm.

Features of Data Acquisition Unit

• A Microcontroller based data acquisition system for data acquisition & indication.

• Two 16 characters * 2 lines LCD displays for displaying load & crosshead travel value.

• Auto-detection of over-load, over travel & specimen break. On detection of any of the above conditions, the machine is automatically switched off.

• Load is indicated with resolution of 0.01% of machine capacity for the entire measurement range ( in other words with resolution of 0.04kN for TUE-C-400 Model)

• Tare load & reset elongation facilities available.

• Elongation is indicated with a resolution 0.1 mm.

• Storage space to store data of 1 off-line test.

The direction control valve is provided which directs oil flow either to analogue control panel. One can use one system at a time.

Both Analogue and computerized control panels are provided together which work exactly same as per described above for analogue & computerized control panel.

When order is placed for analogue cum computerized universal testing machine both the control panels with direction control valve will be supplied.

Application

Universal Testing Machines have a wide range of applications. A number of materials and metals in different forms and shapes can be tested for a variety of tests like Tension, Compression, Transverse, Bend, Shear, Brinell hardness, etc.

Special attachments are also available for testing of flat belts, chain links, wire ropes, etc.

CONSTRUCTION

Loading frame
The base has a hydraulic cylinder at its center, and two main screws at both ends. The middle cross head is mounted on screws through main nuts. The middle cross head can be moved up or down through chain transmission and geared motor to adjust the initial tensile/compression clearance. On the piston rests an assembly of upper, lower crosshead and two columns. The individually lapped cylinder piston assembly ensure smooth transfer of force with minimum friction.

Hydraulic system
Hydraulic circuit consists of hydraulic power pack having a directly driven radial plunger pump which gives a continuous non pulsating flow of oil pressure upto 250 bar. Oil filter, Oil strainer, Air breather, Oil level Indicator, Drain plug are provided on the power pack. A pressure compensated needle type flow control valve, is provided to control the oil flow to cylinder thereby achieving desired piston speed. Infinitely variable speeds can be obtained with the help of valves.

Electrical system
A separate switch box and electrical panels are provided. Both the hydraulic pump motor and the geared motor have interlocks. Limit switches are provided to stop the hydraulic pump motor if the load increases beyond the machine capacity or if the piston stroke is exceeded.

Analogue Control Panal

Load measuring system
The oil pressure in the main cylinder is transferred to the small dynamometer cylinder. The dynamometer piston is kept rotating at a slow speed to ensure dynamic friction condition. The piston exerts a force proportionate to the pressure on the hanger connected to one arm of the pendulum, through an auto range selecting lever system. This force deflects the pendulum. The range selection can be effected by simply turning a knob, provided outside of the panel. An effective damping arrangement is provided to ensure slow return of the pendulum after sudden fracture of the test specimen.

Load indicating arrangement
The pendulum lever pushes rack which slides over two pulleys. The rack movement is proportionate to the load. A pinion in engagement with the rack rotates and moves the pointer fixed to its shaft. The pointer moves over a large dial indication the load. A window type dial is provided for easy and clear change of the load range.

Recording system
A continuous roll type load elongation recorder is provided for plotting a load-elongation graph. Load is plotted by the horizontal movement of the rack. Elongation is plotted on the vertical axis and is equal to the movement of the main piston. Elongation ratio of 1:2 and 1:5 can be obtained.

Accuracy and calibration
All measuring ranges of the machine are calibrated with in an accuracy of ±1 % from 20% to 100% of each range as per IS 1828 and BS 1610