What is Tensile Test? How Tensile Strength Tester Works?

How Tensile Testing Device Works?

Tensile testing device SCOPE

The test method describes methods for determination of strength of attachment of press-studs (poppers), jeans buttons, rivets and snap fasteners to garments.

PRINCIPLE

A sample is taken from the garment, consisting of a sandwich of several fabric layers, through which a press-stud (popper) has been applied. This is subjected to a known load, applied in such a way that the two halves of the press-stud component are pulled in opposing directions, thus tending to prise the two halves apart. Male and female halves of the press-stud are tested separately.

APPARATUS

Tensile testing device of the constant rate of elongation type, capable of determining the applied load to +/- 5% accuracy at a rate of traverse 50+ mm/minute.

Preparation of test specimens and materials (removal from the garment): Cut a parallel strip of fabric from the garment that contains a single male or female press-stud so that the press stud component is positioned centrally on a fabric strip approximately 30mm wide by 150mm long.

TEST PROCEDURE

  • Condition for a minimum of 4 hours at 65+/- 2%rh and a temperature of 20+/- 2  degrees
  • Testing must take place in a conditioned environment.
  • Grip the specimen in the jaws of the tensile test device. Determine the force to remove the press stud component.
  • Test a minimum of ten male and ten female components.

REPORT

  • Report the average press-stud removal force (in Newtons) for the 10 male        components separate from the 10 female components.
  • Report the minimum press-stud removal force (in Newtons) for the male and female components separately.
  • Report if the fabric has broken down and if so at what force, even if the press-stud has not been removed.

Incomplete Heat-Setting-

Definition and Causes

  • With synthetic knit and woven fabrics and with fabrics containing Spandex yarns, a complete Thermo-fixing process must take place.
  • This is done to ensure that after finishing a dimensionally stable fabric is produced and prevents the fabric to exhibit wrinkles and edge curling.
  • This is normally done by exposing the surface of the fabric to temperatures of 360-380 degrees Fahrenheit for a certain period of time (dwell time).
  • This dwell time will be dependant on type of fabric, percentage of the Spandex yarn and the size of the heating chambers.
  • In certain cases in order to prevent heat damage a small quantity of wetting/penetrant type of chemicals need to be added in the Pad tank.

Preventive Suggestions

All technical aspects of the heat-setting process must be examined and appropriate steps need to be taken.

Corrective Measures:A refinishing at a higher than the original temperature will be required.

Excessive Over-Feed and Under-Feed-

Definition and Causes

  • During the drying process the control and stabilizing fabric’s weight (Yield) is an important function.
  • This is, normally, done by devices known as Over-feed (or under-feed) rollers and wheels.
  • In knit fabrics to increase the weight, these devices are made to increase the density of the knitted courses across the width of the fabric in a uniform and precise way.
  • This is referred to as Over-feeding and its excessive use will cause severe crease lines on the selvedge of the fabric on both sides.
  • To decrease the weight, a reverse action takes place. Excessive use of this Under-feed action will cause the fabrics to develop severe creases, particularly, in the middle portion.
  • These problems do not appear in woven fabrics.

Preventive Suggestions:A correct and precise method of finishing, based on the type of fabric must be used.

Corrective Measures:With cotton fabrics, a refinishing at a correct measure of under-feed or over-feed will correct the problem.

Conclusion

With synthetic fabrics, a rewashing of the fabric at pressurized conditions and at high temperatures will be necessary for Tensile Testing Device

About Engr. Kh. Mashiur Rahman

He is Top Class Digital Marketing Expert in bd based on Google Yahoo Alexa Moz analytics reports. He is open source ERP Implementation Expert for RMG Industry. He is certified IT Professional from Aptech, NCC, New Horizons & Post Graduated from London Metropolitan University (External) in ICT . To Hire his service and Him Email- sales@autogarment.com, Cell# +880 1792525354

Similar Post

Top 100 Yarn and Crochet Tools

Top 100 Yarn and Crochet Tools Crochet Tools What is Mohair Textile Yarn Tester? Type …

Leave a Reply

%d bloggers like this: