Electromechanical testing machines EM2 MICROTEST ENGLISH b

8/7/2019 Electromechanical testing machines EM2 MICROTEST ENGLISH b

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Electromechanical Materials Testing Machines EM2 MICROTEST

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Electromechanical Materials

Testing Machines EM2 series

MICROTEST

2011

MICROTEST

MICROTEST, S.A.

Instruments and Equipments for Materials Testing

(+34) 91 796 33 32 www.microtest-sa.com


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MICROTEST EM2/FR electromechanical

testing machines are designed to test a

large range of materials, including: rigid

and reinforced plastics, composites,

ceramics, geo-textiles, concrete,

rocks, mortars, wood, sheet metal,

welded specimens, rubbers, adhesives,

and medical products and components,in tension, compression, flexure, shear, tear

and peel. They are widely used in R&D

Centers, Industry, Testing Laboratories,

Education centers, and for calibration

purposes in Force Calibration Laboratories.

They are built in capacities ranging

from 10kN to 500kN, both tension and

compression. Under demand they can

also be made in lower and bigger

capacities.

In MICROTEST EM2 machines the

load is applied by means of a double

screw driven system in a dual column

frame. The construction of the machine

load frame, with a double guiding

columns and pre-loaded leadscrews,

make these frames have excellent rigiditywith negligible frame deflection.

This design allows for a single test zone

for both tension and compression tests.

Users can load heavy specimens with

minimal effort. This feature is further

enhanced by a programmable switch

mechanism that allows the operator to

quickly set upper and lower crosshead


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limits at any point

within the frames clearance.

The crosshead is actuated by the screwdriven system and guided by two robust

lateral columns. The vertical crosshead

travel is determined for the length of the

screws and can be modified under

demand.

This electromechanical system is a double

effect one and is driven by a DC electric

motor

(or a brushless motor) and includes an

optical encoder for a continuous

measuring of the crosshead position that

allows also the control of the test speed.Inside the lower frame there is a

transmission system transmitting the

mechanical power to the screws, usually

including a heavy duty gearbox and a

pulley system.

The main advantages of electromechanical testing machines over the hydraulic systems are:

High stability, mainly at low speed or long term tests (corrosion under tension tests,

creep tests, etc.).

Capability of keeping the load during long intervals, with error under 0.1% of the

applied force, or even better (< 0,01%) in the case of calibration by comparison force

standard machines or high stability of load tests .

Electromechanical machines can be operated at speeds ranging from a minimum

of 0.001mm to a maximum of 200 or500 mm/min (or even 1000mm/min, depending

on the model), which accommodates a wide range of materials and specimens.

Minimum maintenance: They do not need oil, filter or joints replacement.

They do not need extra space for hydraulic power source and they do not need any

pipe or external fittings to transmit the mechanical power.

Very low noise in comparison with hydraulic systems and without the risk of leakage of

oil.

Low consumption of energy and no need of expensive cooling systems.

Moreover, the displacement of the

crosshead allows the application of the

load without impact, in a continuous way,

disregarding the state of cleanliness ofelectro-valves or servo-valves needed in

hydraulic systems.

MICROTEST EM2/FR machines have ever

shown a very good behavior in long term

tests, where it is necessary to keep the

load or the position during long time at a

high level of stability.


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The electromechanical testing machines

include one or more force transducers

(load cell) that provide better precision

measurement of the applied force than

pressure transducers or gages used in

traditional hydraulic systems. In this way

the force measurement is not affected by

oil temperature, local disturbances

caused by the oil flow, friction in the load

cylinder, etc.

The test speed is digitally controlled and

measured by means of an incremental

optical encoder placed in the motor axis,

obtaining a high precision controlled

movement, helped by the high gear ratio

of the system.


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The EM2 machines flexibility is further

extended by a wide array of accessories

instrumentation, grips and fixtures to

perform all kind of test with the higher

efficiency. These accessories include

various LVDT extensometers,

compressometers, strain gage

extensometers, high temperature

extensometers, as well as grips, holders, jigs

or platens for holding the test specimens.

They can also be delivered with special

testing equipment as high temperature

furnaces, climatic chambers, etc.

MICROTEST can provide a great variety of grips and accessories, depending on the material

or test.Among others:

Compression platens.

Pneumatic or manual grips for tensile tests with different jaws.

Bend fixtures.

Other test fixtures (shear, friction, tear, peel, etc)

Extensometers, furnaces, climatic chambers, etc.


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This flexibility makes EM2 machines very suitable in most of the standardized axial tests,

where the force to be applied is under the load capacity of the machine, in tensile test orcompression tests in the same single test zone.

Among others, with the suitable fixture, the following tests can be done:

Tensile tests on metal samples: standard shapes, ribbons, springs, screws, fasteners,

washers, wires, cables, elastomeric samples, etc

High temperature creep tests

Corrosion under tension tests.

Tensile tests on polymers, composites, rubbers, textiles, ropes, webs, wood, etc.

Tensile tests on standardized steel samples.

Tensile, shear or bending tests on aluminium samples or profiles. Compression tests on concrete, mortars, ceramics, foams, wood, rocks, etc.

Friction tests, peel tests. Shear, etc.

Bending tests on mortars, concrete, ceramics, wood, paving tiles, etc.

CBR and Marshall test.

Calibration of force transducers (EN ISO 376).

Do not hesitate to contact us to consult any need about your tests.


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DESCRIPTION

LOWER CHASSIS

It contains the electromechanical driving

system, composed by: motor, gearbox,

pulleys, ball screws, bearings, etc. and

electric elements to control the machine.

Over this lower structure the load frame

stands.

The base plate of the frame can have

threaded holes, linear guides, holders or

attachments when they have to be used

with climatic chambers, furnaces, etc.

The dimensions of this chassis can be

modified under demand to change the

height of the test zone, for example.

LOAD FRAME

The load frame has a high stiffness, with

two columns in chrome steel and double

ball screw.

The crosshead usually has the load cell for

measuring the force during the tests.Several load cells in different lower

capacities can be added with the

suitable coupling elements.

The crosshead has also the nuts and

bearing units to allow the soft movement

of the crosshead when the screws are

actuated by the driving system.

The dimensions of the load frame can bemodified under demand to change the

height or the width in the test zone, for

example.

ELECTROMECHANICAL ACTUATOR SYSTEM

This electromechanical system is a

double effect one and is driven by a DC

electric motor (or a brushless motor) and

includes an optical encoder for a

continuous measuring of the crosshead

position that allows also the control of the

test speed.

The maximum speed and travel will

depend on the screw, motor and gearbox

used.

Under demand, different solutions can be

adopted to have other values for speed or

crosshead travel.

To make possible an easy collocation of

the samples, the machine has a manual

control for the crosshead in the front panel

of the machine that allows the changing

of the test zone height. The speed of this

movement is selectable by the SCM3000

software.


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SAFETY SHIELD AND PROTECTIVE ELEMENTS

Every standard EM2 machine includes a

protective shield at the front side of the

load frame. This shield is made on a highresistance and transparent polycarbonate

and protects the user from any potential

debris. The machine has also mechanical

and electronic limits features (including

emergency button) supplied to prevent

movement of the actuator beyonddesired regions of operation or in case of

emergency.

CONTROL, MEASUREMENT AND ACQUISITION SYSTEM

- The control and measurement is

performed by the SCM3000 electronic

board developed by MICROTEST. This

electronic board provides a closed loop

control of the machine and analogue to

digital conversion for at least 8 channels.

The control includes digital input/output

lines connected with the machine and

motor driver covering the rest of the

control and security functions of the

control system. The machine control can

be monitored by means of a computer via

USB connection. The software SCM3000

allows also the recording of the different

quantities data during the test.

EM2/FR machines make use of this

SCM3000 software that enhances the

features of the machine for any kind of

test or material, allowing the user the full

control of any of the functionalities of the

machine. Its a very reliable and

adaptable system. The description of the

SCM3000 software specifications is shown

apart. All database and controlled

parameters are managed using acomputer (included) with the MICROTEST

SCM3000 software (English version).

SCM3000 software helps the user to

automate his operations, providing a

powerful Method and Result Editor, with

the possibility of exportation of data to

Excel or ASCII files that allows the

generation of customized reports. The test

curves can also be rescale, recall and

replot by a Graphics Editor

The control system also includes: software

selectable servo-control by force or bydisplacement (or other quantity), displays

for the configured channels, digital

zeroing of any channel, fully configurable

channels, calculated channels,

configurable alarms, digital recording of

every configured quantity, selectable

sampling, automation of the tests (tests

methods and complex sequences of

movement or load), definition of test

parameters, calculations, graphical

display of recorded data and test results,

etc.


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Technical Specifications

(*) Dimensions, weights and supply voltage can be adapted to the customers needs. They are only approximate and

dependant on the specific technical proposal.

(**) Without accessories.

MODEL EM2/02 EM2/10 EM2/20 EM2/50 EM2/100 EM2/200 EM2/300 EM2/500

FORCE

CAPACITYkN 2 10 20 50 100 200 300 500

CROSSHEAD

TRAVEL (typ.)mm 500 700 1200 1200 1300 1200 1200 1200

Columns 2 columns

Type of frame Table top Floor standing

Crosshead

Max. Speed

(typ. values in

bold)

mm/min

50 100 100 100 100 100 100 100

500 500 500 200 200 200 200 2001000 1000 1000 1000 500 - - -

Crosshead min.

Speedmm/min

0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001

0.005 0.005 0.005 0.002 0.002 0.002 0.002 0.002

0.01 0.01 0.01 0.005 0.005 0.005 0.005 0.005

Position

resolutionmm 0.001 0.001 0.001 0.001 0.001 0.001 0.001 0.001

Horizontal test

spacemm 240 400 525 525 530 530 530 710

Max. Vertical

Test space (**)mm 500 700 1200 1200 1300 1200 1200 1200

Stiffness mm/N

Documents

Electromechanical testing machines EM2 MICROTEST ENGLISH b