Aerospace Technic and Technology

To make a decision on determining the periods of safe operation of parachute systems that have exhausted a given resource, it is necessary to know the parameters of their actual technical condition. Experimental destructive methods for determining the parameters of residual strength are considered: breaking strength and relative deformations during the breaking of the standard specimens.

Parachute design elements to be examined include parachute dome fabrics, carcass reinforcement ribbons, strops, and suspension system belts. In order to ensure that all requirements set forth by regulatory documents for conducting an experiment with textiles, specialized devices have been developed, designed, manufactured and tested experimentally. These devices provide strength experiments on a universal tensile machine designed to work with samples of metallic materials.

The need to create specialized devices is caused by a very wide range of braking forces (from tens to several thousand newtons), as well as by the specifics of synthetic textile materials of the parachute design elements. A set of devices has been developed that provide the required conditions for conducting rupture experiments on samples of textile materials. The created devices provide sufficient compressive force of the sample in the clips without slip-page and without violating the integrity of the contact surface of the studied synthetic textile materials. Ensuring that the sample is sufficiently compressed in the clamping devices of the tearing machine is ensured by special transitional gaskets and methods for creating a compressing force on the sample. Compressing devices and devices for conducting experiments with low-strength specimens of the dome fabric, with medium-strong reinforcing skeleton tapes, strops and high-strength straps of the suspension system are created. In order to speed up the preparation of samples for the experiment, methodologies have been created that ensure the required length of the working part of the sample and its fixation without warps. A universal strain gauge was developed to determine the change in the length of the working section of the specimen in 100 mm. Installing the meter on the sample under study allows you to measure displacements up to rupture. The meter is fastened to the specimen using spring clips. The developed devices were tested during the experiment with hundreds of samples of the structural elements of 3 parachutes.

parachute; experiment; strength; deformation; textile samples

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