New York subway tunnel job required 260 caissons.

A New York subway project was a test for both the contractor and its equipment.

In order to survive on the unforgiving streets of New York City, you have to be strong, powerful and fast. As a seasoned veteran of the Big Apple, Ziegenfuss Drilling Co. knows what it takes to succeed in this difficult environment.

The 63rd Street Subway Tunnel Project in New York City proved that only the tough survive. The drilling involved putting down 260 caissons to support a new subway tunnel that will house an additional two tracks. Drilling just inches from "live" rails, the project needed to be completed quickly and without incident.

Upon being awarded the drilling contract, Ziegenfuss Drilling decided to use a Numa Champion 180 down hole hammer to complete the project. A Foremost DR24 drill rig operated the Champion 180 down hole hammer with a 22 1⁄2-inch bit at 150 psi of air and 2,000 cfm. Placed inside 24-inch casing with Foremost's patented casing shoe attached to the bottom, the C180 hammer easily drilled down 39 feet to 48 feet through very unconsolidated formations consisting of concrete, sand, boulders, cobbles, brick and wood - nothing could stand in Ziegenfuss's way.

The New York City streets can be tough, but as Ziegenfuss Drilling proved, not too tough for a quality drilling contractor using quality products.

Project: 63rd St. Subway, New York City
Application: Drilling and casing 260 supports
Hole size: 24 inches
Depth: 39 feet to 48 feet
Formation: Concrete, sand, boulders, cobbles, brick and wood
Rig: Foremost Dual Rotary DR24
Hammer: Numa Champion 180