中文版   English   会议系统
Introduction Hydroforming Tools Applications Contact
Category:
Words:
   
 
· 哈尔滨工业大学
· 哈尔滨工业大学材料学院
· 方舟软件
· 华军软件园
· Google搜索
· 百度搜索
 
 
Your current position:Home - Testing System for Hydro-Formability of Tube

Testing System for Hydro-Formability of Tube

  2010年03月08日

1. Introduction to direct testing and evaluation of
tube hydro-formability

Hydro-bulging test is used to test and evaluate the properties of tubular materials. Based on the unified
analytical model proposed and the linear-model for pole thickness, a new testing method termed as
linear-model based hydro-bulging test is developed and applied for extruded aluminum alloy tube and
roll-welded steel tube. Only the thickness before and after testing is needed. The effective stress-strain
curve, mechanical properties and formability, can be determined directly

2. Construction and features of the testing system
for hydro-formability of tube developed by HIT

【CONSTRUCTION】 The testing system for hydro-formability of tube is developed based on the unified
analytical model and the direct testing method for hydro-bulging test. Two patent have been awarded
(ZL200610010154.4, ZL200910071699.X) and one computer software has been registered (No.
2013SR108454). The testing system is composed by constraining frame, hydraulic system, high-pressure
system, computer control system, measuring and analyzing system. Main parameters of the system:
 

Maxinum bulging pressure 160 MPa;
Maxinum cylinder force 500 kN;
Variation of bulging height ~50 mm;
Range of tube diameter 20-110 mm;
Range of tube length 120~300 mm.


Testing system for tube hydro-formability


Interface of the testing system

【FEATURES】
(1) No need to cut the tube specimen. Mechanical properties and formability can be obtained directly. 
(2) Effective stress-strain curve and formability of anisotropic tube under complex stress state can be obtained. 
(3) Only initial and final pole thickness are required. Instant thickness change can be calculated according 
to Linear Model. The error caused by discontinuous measuring or multi-specimen method can be avoided. 
(4) Properties of sheet metal under complex stress state can be tested by using roll-welded tubular specimen. 
 

3. Output results

The following mechanical properties and parameters can be determined:
(1) Limit fracturing pressure; 
(2) Maximum bulging ratio;
(3) True stress-strain curve;
(4) Engineering stress-strain curve;
(5) Yield stress;
(6) Tensile strength; 
(7) Strain hardening coefficient, n-value;
(8) Forming limit diagram, FLD. 

Interface of data analysis
 

4. Main achievements

The testing system (THF.HIT-160/110-A) has been successfully transferred to industries, such as FAW, Anshan Steel, and Jiangyin Jieda shaped-tube. The testing results of different tubes have been used in numerical simulation of hydroforming process, also in the determination of process parameters.
 
Mechanical properties of typical tubes

Stress-strain curve of mild steel tube

FLD of aluminum alloy 6061 tube
 

 
 

Copyright: Harbin Institute of Technology hydraulic forming Engineering Research Center to contact us:syuan@hit.edu.cn
Copyright © 2010-2011 hydro-forming.com by Harbin Institute of Technology contact us at syuan@hit.edu.cn All rights reserved.