Stewart & Stevenson Services, Inc.

Milo A Persinger

Robert A Baten

William L Anderson, Jr

Richard I Cushman

A heat exchanger tube bundle extractor having an improved sled and motive means operable to move the tube bundle into or out of its shell. A fixed screw shaft is provided on the chassis, and a rotatable drive nut on the sled. The drive nut is threadedly retained on the screw shaft. The drive nut is held against axial movement with respect to the sled by a gear box disposed on the sled. The gear box output includes a rotating shaft to which the drive nut is connected, which provides the drive nut with the appropriate speed and power to effectively pull the tube bundle from, or push it back into, the shell. A balance nut disposed on the opposite end of the drive shaft from the drive nut, and threadedly engaged with the screw shaft, reacts against side forces on the sled and screw shaft to assist in keeping the drive nut and screw shaft properly aligned. All of the power generation, conversion, and control equipment for operating the sled drive, a hydraulic breakout cylinder, and a hydraulic elevator is located on the sled itself in a compact and self-contained arrangement, and is movable along with the sled. This eliminates the piping, cabling, and related power equipment from the chassis. The present invention exhibits a low unit weight to pulling/pushing power ratio, and a low unit weight to load capacity ratio.

Growing community of inventors

Kerrville, TX, United States of America

Milo A Persinger