At the beginning of 2026, Univer successfully delivered a 600 kN horizontal tensile testing machine to a European customer, designed for stress–strain and creep testing of overhead conductors and OPGW used in power transmission applications.

Overview

This machine is engineered to deliver high-capacity, long-span mechanical testing with the following core specifications:

• 600 kN capacity
• Adjustable grip spacing: up to 22 m, in 0.5 m increments
• Maximum loading stroke: 2 m
• Temperature control range: –40°C to +80°C

It is primarily designed to perform the following four categories of tests:

1. Stress–strain tests on overhead conductors
2. Tensile tests on fittings used for overhead conductors
3. Creep tests on overhead conductors, OPGW, and optical fiber cables
4. Thermomechanical pre-stress tests on insulators

Additionally, the system can be used for any other applications requiring both high load capacity and extended test spans.

Detailed Description

The system consists of several major components, each optimized for specific testing requirements:

Sample End Preparation

Two preparation methods are available to accommodate different specimen types:

1. Compressed fittings
2. Low-melting-alloy casting method

Extensometer for Stress–Strain Testing of Overhead Conductors

• Fully adjustable gauge length throughout the entire test span (2 m to 20 m)
• Each gauge probe supports a measurement range of up to 1 m
• A mechanical protection mechanism enables testing to failure without manually removing the extensometers

Extensometer for Creep Testing of Conductors and Optical Fiber Cables

• Adjustable gauge length across the full 2 m to 20 m span
• High-resolution measurement capability up to 0.5 μm

Temperature Chamber for Thermomechanical Testing of Insulators

• Internal dimensions: 4 m length, 0.4 m width
• Temperature range: –40°C to +80°C
• Temperature change rate: up to 2°C/min

Features

• The electromechanical loading system delivers smooth and stable loading with low power consumption, enabling continuous testing for durations of up to several thousand hours.
• Electromagnetic brake system maintains tensile load in the event of a power outage
• Portable, foldable support stands positioned along the test zone prevent conductor sagging
• Automatic test recovery allows the software to resume testing after power is restored
• Programmable testing workflows let users customize procedures for specific applications
• Safety doors ensure secure operation during testing