Impact pendulum Research and Development

THE SOLUTION PROVIDED BY LF TECHNOLOGIES

Our client is a research and development centre specialising in materials.

Main functions

Objective

Carry out impact bending tests on Charpy specimens in accordance with standards NF EN ISO 148-1, NF EN ISO 148-2, NF EN ISO 148-3 and NF EN ISO 14556, with an automatic specimen temperature control system, from -180°C to +600°C.

PROBLEMATIC ISSUES

The problem of the impact pendulum

To ensure automatic positioning of the pendulum as well as on-the-fly catch-up after impact.
Ensure that the arm catches up after the impact so that the specimen is not re-taped after the first impact (making the test null and void as it is impossible to study specimen falls).
Reliable force/displacement measurement that is easy to calibrate
Facilitate verification and calibration procedures for the imapct pendulum

Thermal enclosure issues

Impact bending tests are carried out in accordance with standards. In the case of temperature tests, these standards impose strict temperature control and conditioning of the test specimens: temperature regulation, location of the measurement, spacing between the test specimens, transfer time between the thermal chamber and the pendulum.

Once the test tube has been warmed up, it must be placed on the pendulum and tested within 5s of leaving the chamber.

SOLUTION AND RESULT

Imapct pendulum

The specimen support is fitted with a centring device. This device presses the specimen against the supports and ensures centring just before impact. The test piece is centred by its notch.

The pendulum arm is linked to a motorised arm. This motorised arm follows (without touching) the pendulum arm during release and reattaches it on the fly. This motorised arm can also be used to raise the pendulum arm to the desired release height.

The machine is equipped with several control systems to check the geometry of the pendulum, its moment and the response of the force transducer, enabling direct checks to be made in accordance with the standard.

Thermal enclosure

LF Technologies imagined and designed a thermal enclosure with a test tube conveyor. This conveyor ensures that the spacing between test specimens complies with standards.

The thermal chamber is also equipped with a system for transferring specimens to the pendulum. This transfer system is a “shovel” that positions the test tube in the pendulum. The movements of the “shovel” and the pendulum are synchronised, ensuring a very short transfer time (time between temperature conditioning exit and shock less than 5 seconds).

The thermal chamber allows temperature control from -180 to +600°C while ensuring efficient temperature control and transfer of the test specimens.

Tested product

Steel test tubes

The steel specimen is a characteristic sample of the material to be tested.

The aim of the impact bending test is to determine the energy required to break the specimen, which enables the material’s resilience to be characterised. The type of impact (force/displacement curve) can also be used to determine certain specific characteristics of the material.

The impact bending test can be carried out at room temperature, or with a temperature-conditioned specimen. For a given material, the variation in resilience as a function of temperature can be used to determine a curve corresponding to the change in resistance of the material as a function of temperature.

Impact pendulum Research and Development

Pendulum hammer + thermal enclosure

Impact pendulum test bench open house

Impact pendulum test bench and thermal enclosure

Installing the test piece in the test area

Impact pendulum test bench test tube

Thermal enclosure

Mobile Impact pendulum test bench carriage

Impact pendulum Research and Development

The test rig is a pendulum impactor with a U-shaped hammer that can be fitted with different weights to perform tests ranging from 300J to 800J.

OUR KEY TEST BENCH FOR THESE TESTS Mouton Pendule – Charpy Impact, Izod MCMP

Main functions

Impact resistance is one of the most important properties to consider when designing a part or appliance. LF Technologies’ Impact pendulum testing machine is used to determine the resilience of a sample to an impact generated on it in accordance with ASTM and ISO standards. Impact pendulum test machines perform precise and repeatable impacts on a wide range of materials to determine the mechanical and physical characteristics of metals, polymers, composites, whether for R & D or quality control in production. Our machines carry out Charpy and Izod tests, which meet international standards. Our machines perform Charpy and Izod tests, which meet international standards.

Operating mode

The automatic specimen centering system ensures a simple and effective use of the impact pendulum. The specimens are impacted within 5 seconds following their removal from the temperature unit. The use is simplified thanks to the rapid change of the knife and specimens supports.

The motorized impact pendulum is equipped with a pneumatic hammer release system. The hammer resetting process is motorized for a better ease of use. A protective casing protects the operators during the displacement of the hammer.