PIT (HFMI) Technology

Pneumatic Impact Treatment (PIT) is a High Frequency Mechanical Impact (HFMI) method used to significantly extend the fatigue life of welded structures.

How It Works

The PIT method uses hardened steel pins driven by compressed air at high frequency (90 Hz) to hammer the weld toe. This process achieves two critical engineering improvements simultaneously:

  • Plastic Deformation: It modifies the weld toe geometry, rounding out sharp notches and reducing stress concentration factors.
  • Compressive Residual Stress: It introduces deep compressive stresses into the metal surface, which prevents crack initiation and propagation.
HFMI Application on Weld
PIT Hardware Kit

Technical Specifications

The PIT system is designed for mobility and durability. It requires only standard compressed air, making it ideal for on-site offshore, bridge, and heavy industry applications.

Impact Frequency 90 Hz
Air Pressure Required 6 - 8 bar
Treatment Speed Approx. 30 cm / minute
Pin Radius 2mm, 3mm, or 4mm (Exchangeable)
Vibration Emission Low (Damped Handle System)

Why Use PIT?

Life Extension

Can extend the fatigue life of welded joints by a factor of 4x to 10x depending on the load spectrum.

Highest FAT Class

Allows engineers to design utilizing higher fatigue classes (FAT) according to IIW and DNV guidelines.

Stress Corrosion

Prevent Stress Corrosion Cracking (SCC) by neutralizing tensile stresses at the surface.

Equipment Rental & Services

We offer PIT equipment rental, pin supplies, and on-site treatment services.

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