Abstract: An in situ machine is provided for refurbishing a bore in a workpiece. The achine includes a shaft which is adapted to be fixed to the workpiece in axial alignment therewith. A tubular boring element is concentrically mounted for rotation about the fixed shaft and is adapted to extend into the workpiece bore. A cutting head is slidably mounted on the boring element for reciprocable movement therealong. A device is provided for rotating the boring element and cutting means, and another device, which is responsive to the rotating device, is provided for advancing the cutting head along the boring element.

Abstract: A portable machine is provided for in-place grinding of an inside ellipti face of an elliptical boiler manhole access with a grinder which has a flat grinding surface. The boiler manhole access also has an outside elliptical face and a conforming elliptical edge therebetween. The machine includes a supporting structure which is adapted to be fixedly mounted in the manhole access and span the elliptical inside edge. A spindle is rotatably mounted on the support structure with its longitudinal axis substantially coextensive with the longitudinal axis of the manhole access. A sleeve is fixedly mounted to one end of the spindle in a direction perpendicular thereto, and an elongated hollow slide means is slidably mounted on the sleeve. The slide and the sleeve are in gas communication with one another so that when gas pressure is applied thereto the slide is outwardly spring biased from the spindle. The grinder is mounted to the slide with the grinding surface engageable with the inside elliptical face.