Experimental studies on the stress corrosion process have shown that applying an anodic current to metals can accelerate stress corrosion, while applying a cathodic current can halt it. It is generally believed that compressive stress has little effect on stress corrosion. Tensile stress is usually present, but experiments have found that compressive stress can sometimes also cause stress corrosion.

LETRY stress corrosion rings are widely used in the production testing and research of high-quality materials. Under the influence of H2S, accurate use of stress ring testing can obtain corrosion effect data for various materials in acidic and alkaline corrosive environments, such as petroleum exploration, aerospace, welding seals, marine vessels, and food processing. It also allows for a precise understanding of material load capacity and is the most economical and effective testing instrument for determining the susceptibility of metals to stress corrosion cracking caused by sulfides.

Main functions of LETRY stress corrosion rings:

1. Constant stress tensile testing;

2. High-temperature creep testing;

3. 1/2 CT specimen crack growth rate measurement testing.

Main technical specifications:

1. Complies with NACE TM 01-77 experimental standards;

2. Load range: maximum 0–250,000 psi;

Stress ring load selection range: 0–100,000 psi; 0–150,000 psi; 0–200,000 psi;

0–250,000 psi; Load error: ≤1%

3. Load linearity ≥0.9999;

4. High elastic deformation reversibility, ensuring an error of less than 2% within 5 years;

5. PLC automatic timing system with high reliability.

6. M10 metric round specimen;

7. 1/2 CT specimen

8. M6 metric fine round specimen.