GRAY 527873 VERTICAL BORING MILL

Technical Description

The GRAY 527873 Vertical Boring Mill is a robust, two-range machine featuring a 120-inch table diameter and a maximum swing of 132 inches. It has a substantial load capacity of 172,000 pounds at maximum RPM. The machine stands 24 feet 8 inches tall, with a rail height of 40 inches. It is equipped with both Right and Left Hand Face Heads, which are Ram Type, Nonswivel, and feature fixed 4-position qualified tool blocks for 2-inch tools. Key dimensions include a maximum height under the rail head saddle of 102 inches and a minimum of 24 inches, while the maximum height under the tool block is 90 inches. The ram size is 12 inches by 12 inches, with a vertical travel of 72 inches. Horizontal travel allows the ram head to reach 74 inches to the table center and 1 inch past it. Power is delivered by a 125 HP motor at 650 RPM, driving the table speed infinitely variable from 1 to 50 RPM, split into a high range (16.2 to 50 RPM) and a low range (6.5 to 20 RPM). The feed range is 0.01 to 120 inches per minute. Originally installed in September 1973, it uses a Reversing SCR table drive and a GE 7500 NC control system, complemented by Hydraulic Servo Motor Drives for the heads and rams.