Refinery Critical Infrastructure Management: Compressor Foundations

Introduction

Large reciprocating compressors used in most industrial process plants are critical to operations and represent a significant capital investment. Asset integrity programs establish management systems with personnel trained and certified to operate, monitor, inspect, and maintain the equipment. Unfortunately, as they are often taken for granted, the integrity of supporting structural foundations may sometimes not receive the attention deserved. This article is intended to provide some focus on some essentials to consider with regard to the integrity of structural foundations.

Structural foundations degrade for various reasons. When such degradation occurs, the performance of the foundation can have an impact on the reliability of the compressor itself. Recognizing the signs of a degraded compressor foundation through focused inspections, properly diagnosing the root cause, and intervening in a timely manner can save the facility maintenance costs, improve production availability, and significantly impact the bottom line. In the experiences of the authors, foundation inspections may cost between $10,000 and $30,000 USD. Foundation repairs, depending on the extent of the repair, may range between $100,000 and $2 million. A small investment in the inspection and timely intervention to correct the condition can result in significant cost savings. 

Industry codes, standards, and recommended practices such as ISO, ASME, ANSI, API, etc. have matured relative to the inspection and maintenance of process equipment itself. Such recommended and generally accepted good engineering practices (RAGAGEPs) for foundations supporting compressors and other rotating equipment are relatively new or, for some applications, non-existent.

As an operator of a process facility, you should ask yourself: “Does my program adequately cover the integrity of my supporting compressor foundations?” This article should help you answer that question and fill some of this void by covering:

• essential elements of a properly functioning compressor foundation, 
• foundation/machine interaction and problems,
• foundation integrity inspections,
• root cause diagnosis and engineered solutions, and
• considerations for repair implementation.

Guidance provided in this article can be applied to other machine foundations such as fans, generators, pumps, and turbines.