Engineered Casting Repair Service, Inc.

Compressors

Neuman & Esser Ethylene Feed Compressor

survey of damages
This compressor is a vertical configuration, single stage two cylinder compressor of approximately 1000hp at 420 rpm located in Argentina. One of the two cylinders suffered a catastrophic wreck involving the crosshead in the crosshead guide liner. This wreck resulted in the destruction of the crosshead slide guide liner and its supporting structure in the upper frame of the cast iron crank case. The supporting structure for each cylinder in the upper frame of the crankcase consist of 4 vertical ribs and 2 support rings. As a result of the wreck, a significant amount of the vertical support ribs were damaged along with the support rings. The damage resulted in approximately 156" and the loss of the support structure for the guide liner. Below is both a picture and a model of the damage done to the slide guide support structure.

repair procedures performed
Before any repair work was done, ECRS performed multiple wireline tests to assure that the alignment of the main bearing pedestals was not distorted during the wreck. The next repair procedure was to fabricate replacement sections which were then attached to the existing ribs by the method of metalock® and metalace. Where applicable, three-quarter-inch(3/4") bolts were tapped into the replacement sections from the exterior wall of the crankcase to provide additional strength.

installation of reinforcement
Additional reinforcement was in the form of 3/4" steel plates manufactured to the same profile as the original ribs. These plates were carefully trial fitted to the inside of the existing ribs, then mounted using a pattern of 3/4" bolts.

At this point, everything was back together except for the upper and lower rings. ECRS designed replacement rings earlier and had been overseeing the machining of these. When these rings were completed, special care was taken to properly position the rings. Once concentricity of the cylinder register fits and the bores of the ring sections was confirmed, the rings were properly welded into place. ECRS provided assistance in the final machining of the affected areas of the crankcase, specifically, the top surface of the upper ring and the respective bores of the upper and lower ring. This machining was performed at a local machine shop near the job site. We oversaw all of the handling as well as the final machining of the piece.

repair complete
Once the machining was complete, our job in Argentina was complete.

FEA analysis
In addition to the repair, ECRS performed a failure analysis of the crosshead. A model was constructed, and the loading was applied. The results showed a high stress area at the center hole in the top of the component. This is shown in the following images.

Ingersoll-Rand HHE Electric Motor Crankcase

survey of damages
This I-R electric motor reciprocating compressor was severely damaged when a connecting rod failed nearly splitting the main frame in half. After the wreck, only 30% of the original cross-section of the frame was in tact. Following are some pictures of the damage.

repairs procedures performed
The repair of this case required the installation of 4 newly cast sections to replace the broken out areas as well as 60 inches of crack repair. The pictures below depict the installation of two of the replacement sections.

repair complete
After ECRS repaired this compressor, it was put back into operation immediately. As a footnote, this frame is still in service after 15 years of operation.