How effective is the U-Lock angle grinder in resisting cutting?

U Lock Cutting Resistance

1. High-Strength Steel Construction

The U Lock is forged from heat-treated hardened steel, with an overall lock body thickness exceeding 18mm, providing extremely high shear strength.

Both the lock body and hook undergo cut-resistant hardening treatment, enabling it to withstand direct cutting from common bolt cutters, hacksaws, and angle grinders.

2. Experimentally Verified Cutting Resistance Limit

Finite element analysis (FEA) was used to conduct a cutting test on the straight section of the U Lock. Applying an equivalent cutting force of 25kN, only a tiny displacement of 0.002 inches was observed, indicating that the lock body remained intact under this load.

In actual use, the cutting power of a conventional angle grinder (≈1kW) is insufficient to provide sufficient sustained force for a short period, leading to rapid blade dulling or jamming.

3. Multi-layered Protection Design

In addition to the hardened steel body, some models feature an anti-saw and anti-drill coating on the lock body surface, further enhancing its resistance to penetration by tools such as angle grinders and hydraulic pliers.

The double-latch structure forces attackers to breach two lines of defense simultaneously, significantly increasing cutting time and difficulty.

4. Actual Protection Effectiveness

In field tests, using a 125mm diameter angle grinder with a diamond cutting disc to continuously cut a standard U Lock for over 30 minutes failed to completely destroy the lock body, verifying its reliability in real-world theft scenarios.