Dumbbell shaped samples are primarily required for testing tensile strength of rubbers, plastic, and other polymer products. This particular shape with its fixed dimensions is decided for the specimen by standardization authorities. Thus, for a stable and accurate test result, it is important to use a specimen of a standard shape and size. This can be done by preparing the specimen in a scientific manner using an accurate Dumbbell cutting press.

How should an ideal dumbbell-shaped specimen be?

The standardized sample possesses a shoulder at each end and a gauge-like segment on the center portion. The shoulders are wider than the gauge segment which generates a stress concentration in the middle portion when the sample is pulled under a particular amount of tensile force. This stress concentration ensures a higher probability that the sample will rupture from the ends. When the sample is ruptured from the midsection, it is attributed to the material reaching its maximum tensile strength. Whereas if the sample ruptures at one of the ends or in the grip itself the failure may be attributed to improper loading or a pre-existing defect in the material.

How to cut the specimen using the machine?

To get a standardly sized specimen using the cutting machine, follow the below-mentioned steps:

  1. Adjust the testing sample between the dynamic plate and stationary plate.
  2. Lock the pressure release pin.
  3. Push up the handle to move the sample closer to the upper side of the dynamic plate.
  4. After cutting the sample, release the pressure for automatic downward movement of the dynamic plate.
  5. Now the testing sample can be analyzed by the user for the further testing method.

For obtaining a standardized shaped specimen you may opt for Labtiger’s dumbbell cutting press, which is precisely designed to cut specimens for tensile testing methods. The capacity of this press is about 2 ton. The equipment is built on a rigid metallic base plate having autumn gray & blue painting combination. Bright chrome/zinc plating is offers a corrosion resistant finishing offering long working life. The machine comes with an instruction guide and a certificate validating its calibration and standards compliance. All the required standards such as ASTM are followed while designing the testing instrument.

For more information on the testing instrument or to get any sort of technical assistance, kindly contact our team here.