HUALONG|Tensile & Crush testing machine|GLY-1000|Optical fibre cable
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Optical Fiber Cable Tensile & Crush Testing Machine GLY Series │ GLY-1000 - These machines offer force, displacement or deformation closed loop testing. The load frames are rigid constructed, providing superior axial and lateral stiffness. Method E1: Tensile performance This measuring method applies to optical fiber cables which are tested at a particular tensile strength in order to examine the behavior of the attenuation and/or the fiber elongation strain as a function of the load on a cable which may occur during installation. This method is intended to be non-destructive (the tension applied shall be within the operational values). IEC-60794-1-2 Method E1 Object This measuring method applies to optical fiber cables, which are tested at particular tensile strength in order to examine the behavior of the attenuation and the fiber elongation strain as a function of the load on a cable, which may occur during installation and/or operation. Sample The cable length under test us 150 meters, Additional cable length is needed to connect the fibers to be tester. Apparatus The apparatus consists of: 1. An attenuation measuring apparatus, typically an OTDR 2. A fiber elongation strain measuring apparatus based on dispersion testing equipment 3. A specially designed tensile test machine capable of tensioning 150 meters of optical cable in six legs of 25 meters each. The machine is equipped with a motor for controlled tensioning and a load cell for measuring the actual tension applied on the cable. Method E3: Crush The purpose of this test is to determine the ability of an optical fiber cable to withstand crushing. Procedure The cable is wound in the machine over appropriately sized sheaves. The cable ends extend to reach the measuring instruments. A pre-determined number of fibers within the cable are concatenated by fusion splicing. Typically, two sets of fibers are used, one will serve to measure attenuation change and the other serves for elongation monitoring. After all initial measurements and calibration are carried out, the cable is pulled at a specified rate until a pre-determined tension is applied. The cable is laid to rest under tension as per detail specifications, and then the attenuation and fiber length are measured. This process may involve several tensile levels in order to characterize the entire tensile behavior of the cable, or be carried out only at the defined maximum allowed tension level. Pass/Fail criteria Under load, the fiber attenuation is not increased more than a predetermined value, typically 0.05dB over fiber length measured. Under load, the fiber does elongation by more than a pre-determined value over its initial length. The allowed elongation under installation load is typically 0.25%. Crush (Compression) per IEC-60794-1-2 Method E3 Object The purpose of this test is to determine the ability of an optical fiber cable to withstand compression. Sample The sample is a representative cable length sufficient to carry out the specified test. Apparatus The apparatus allows a sample of cable to be crushed between a flat steel base plate and a moveable 100 mm long steel plate. The edges of the moveable plate are rounded with a radius of about 5 mm. Procedure 1. The cable sample is mounted between the plates so that lateral movement is prevented, and a predetermined force is applied gradually. The maximum applied force is typically maintained for 10 minutes.

2. Two types of measurements may be defined. 3. The fiber attenuation is measured at the end of the 10-minute period while the cable is still under pressure. 4. The fiber attenuation is measured 5 minutes after pressure. This requirement is usually carried out at higher compressive loads than the previously described measurement. Pass/Fail criteria • The attenuation must not change by more than pre-determined value, typically 0.05dB. • In all cases, the cable elements should not fracture or crack. Signs of compression are not considered as damage to the cable elements. Load frame Stiff...