Two-ferrule fitting bending fatigue testing machine

Abstract

A two-ferrule fitting bending fatigue testing machine comprises an upper platform provided with a horizontal slideway, a lower platform provided with an arc-shaped slideway, a stand column connecting the upper platform with the lower platform, an upper locking device and a lower locking device, wherein the upper locking device and the lower locking device are used for clamping the two ends of a part to be tested, the lower end of the upper locking device is fixed to a calibration platform, and the calibration platform can slide on the slideways under the driving of a lead screw; the lower end of the lower locking device is fixed to an arc-shaped mobile platform, and the arc-shaped mobile platform can slide along the arc-shaped slideway under the driving of a cam and a cam transmission system. The machine further comprises a hydraulic system providing pressure for the part to be tested, a strain gauge used for testing the stress change of the part to be tested, and an electronic control cabinet. By the adoption of the machine, bending fatigue testing can be conducted on a steel tube provided with two ferrules, precision is improved greatly, stress adjustment efficiency is high, displacement control precision is high, the accuracy of experiment results is high, and the using safety of products is improved.

Description

technical field [0001] The invention belongs to the technical field of physical and chemical measuring devices, in particular to a double ferrule joint bending fatigue testing machine for detecting the bending fatigue performance of double ferrule joints and steel pipes. Background technique [0002] The double ferrule joint was invented in 1947 by American Fred A. Raynen. Compared with threaded, reaming, single ferrule and other joint forms, double ferrule pipe joint is a small diameter pipe connection that takes into account both sealing and safety. Dual tube fittings offer the following advantages: [0003] (1) Withstand pressure up to pipe burst without leakage. [0004] (2) Can be used in vacuum and high pressure liquid systems. [0005] (3) It can work in a low temperature state to ensure sealing, and can also maintain a durable sealing at the highest rated temperature of the pipe. [0006] (4) It can be disassembled repeatedly and the seal is guaranteed. [0007]...

AI Technical Summary

Problems solved by technology

At present, there is no bending fatigue testing machine specially suitable for double-barrel joints in China. The testing of related products currently uses vibration devices or other oil cylinder structures. Due to the small bending displacement of steel pipes and high precision requirements, oil cylinders, air cylinders and other structures are used. Control accuracy is not easy to complete displacement control, and often the conventional fatigue testing machine only has a single displacement fatigue test, and cannot realize strain measurement and control, pressurization and other functions

In summary, the current joint and steel pipe bending fatigue performance testing machine can only achieve a single displacement control, and the accuracy is not high, the stress adjustment efficiency is not high, the control displacement accuracy is low, and the accuracy of the experimental results is poor, which seriously affects the The effect of the product

Images