Blade geometry, materials used in the construction of the blade as well as the manufacturing process and heat treating are all contributing factors in cutter blade design and ultimately cut capability.
The most successful tool position for cutting through a highly reinforced B-Pillar post is parallel with the vehicle’s body ring with most of the current hydraulic cutters built today. The blades are able to close more before coming into contact with the metal, letting them generate more force than if the tool was fully open, and perpendicular to the vehicle. This means the tool is positioned in the window which could potentially block access to the injured occupant for medical care, or worse, the rescue cutter could rotate inward making contact with the patient.
- The Hurst Jaws of Life® S-700 and JL-500 cutter design has improved blade geometry which now enables the cutter blades to attain their maximum cutting capability when near the fully open position.
- The S-700 and JL-500 cutter blade have three distinct cutting angles.
- In addition, the transmission of energy from the piston through the linkage to the cutter blades now reaches its maximum cut capability at a five inch opening.
Today’s modern vehicles use highly advanced types of steel in their construction. The highly reinforced structures in today’s vehicles do not compress into a tight bundle like the A-Posts, Roof Rails and B-Posts of passenger cars built in the 80’s and 90’s. Instead, when the cutter blades make contact with the high-strength outer layer of steel in today’s posts, they are immediately up against the ultra-high-strength Martinsite Boron sheet metal which lines the inside diameter of that structure.
- The S-700 and JL-500 has maximum compressive forces in the near open position. As the blades close, the Martinsite steel cracks and fractures.
- As the cutters continue to close, blade angles change resulting in improved draw of the post material to the strongest cutting area at the rear of the blades.
Premium quality components used in the construction include:
- Forged 7075 T6 – 83,000 pounds tensile strength aviation grade aluminum alloy cylinder body.
- Hurst uses a forged shock-resistant tool steel that has been uniquely heat treated using a four-step tempering process in all the Jaws of Life® cutter blades which makes the blades chip and dent resistant while maintaining ductility.
- This is crucial when cutting Martinsite Hot Stamped Boron sheet metal and Pressure Hardened Boron Steel that is wrapped with multiple layers of high-strength, low-alloy steel.
Be safe out there!