Martindale Wear and Abrasion Testing Machine
No. W.T. 37
The purpose of this machine is to compare the resistance of fabrics to abrasion. The instrument is designed to produce a controlled
amount of rubbing between fabric surfaces, at comparatively low pressures and in continuously changing directions. It is suitable for
testing woven, knitted and other fabric constructions of all weights. Conforms to B.S., A.S.T.M., I.S.O., I.W.T.O., and W.I.R.A.
specifications and standards.
Approximate shipping weights and measurements:
Packing case: 100 x 76 x 70cm
Gross Weight : 150 Kg
Nett Weight: 80 Kg.
Specification
Up to four specimens are tested simultaneously. Each one is prepared and mounted separately in a holder, so as tob expose an area of
6.45cm2 (1 inch2) for testing. The specimen is backed with polyurethane foam and is fixed firmly in position. The abradent - generally
a standard white worsted crossbred fabric, is mounted over a woven felt backing on the abrading tables.
The path traced by the test specimens over the abradent is known as a Lissajous figure. It changes from a circle to gradually
narrowing ellipses until it becomes a straight line, from which progressively widening ellipses develop, in a diagonally opposite
direction, before the pattern is repeated. This continuously changing movement ensures that the surface fibres of the specimens are
flexed in every direction. However, by a simple interchange of driving pegs the Lissajous figure may for special purposes, be converted
into a regular reciprocating motion.
There are several ways of assessing the test results. The specimens may be compared visually after a certain number of rubs.
Alternatively, the test may be continued until a particular end point is reached, e.g. when holes appear. However, the most objective
method is to remove the specimens at intervals, condition and weight them, so as to determine the rate of weight loss.
The Martindale Abrasion tester is an extremely useful and versatile laboratory testing machine. Some of its more important areas of
application are listed below.
- To compare the abrasion resistance of fabrics which have been subjected to different dyeing finishing or other treatments.
- To compare the pilling tendency of knitted fabrics.
- To compare the fastness of dyes to rubbing.
- To compare the resistance to abrasion of materials intended for collars and cuffs.
- To compare the effect on specimens, e.g. front trousers, of cloth to cloth rubbing.
The instrument is soundly constructed. It is mounted on a fabricated steel base. The motive power is obtained from a 0.3 hp motor,
set in a flexible cradle to minimize vibration. The motor is coupled directly to three individual, fully enclosed spiral gearboxes. All
the working parts of the instrument are machined and accurate to within close limits. A pre-settable electric impulse counter which
stops the machine automatically after a pre-selected number of rubs, and a totalizer are incorporated for total operator convenience.
Also as per the illustration a clear perspex cover is fitted over the rubbing plate area to ensure maximum operational safety |
