Surgical tubing is used in a wide range of applications, such as drains, feeding tubes, irrigation and surgical procedures, and come in a variety of shapes and sizes with dozens of possible interconnections and fittings. The mechanical performance of these tubings is critical, as failure could seriously endanger patients. Testing requirements include failure of the material, failure at joints and simulation of physiological parameters. In more advanced cases, tortuosity tests may be used to evaluate frictional forces experienced within catheters as they are fed through arterial vessels. In all testing applications, whether you are evaluating the mechanical properties of the surgical tubing itself, or if you are assessing the strength of the connection between the tubing and the fittings, correct gripping of the tubing is essential for obtaining accurate measurements.
Depending on your specimen, we suggest using either pneumatic cord and yarn grips or manual capstan grips. These grips will help ensure that your test specimens fall with the gauge area. For determining modulus and yield calculations, we suggest using a non-contacting strain measurement device to accurately measure elongation. The non-contacting extensometer also prevents failure due to knife-edges or clip-on style extensometers. For this test, we used a 3345 universal testing system configured with side-action screw grips and serrated faces. We compared the strength of a surgical fitting with the ultimate strength of the tubing material.
However, if you are performing more advanced applications, such as evaluating the frictional force of a surgical tubing in tortuosity tests, we suggest that you use a horizontal test configuration. If you are using our software, you will be able to design your own test method for measuring various frictional, insertion and removal forces for all types of tubing. In addition, if your specimen needs to be tested in physiological conditions, we suggest using an environmental bath that can be added to either a horizontal or upright test frame.