Gas 2023 Issue

Digitally enhanced reciprocating compressor performance With instant access to compressor data, improved productivity, and expert support, digital technologies are revolutionising maintenance processes

James Litchfield and Philipp Wolschner Burckhardt Compression

A s the technology for connecting machinery and gathering important data continues to improve, more companies are seeing how they can reduce costs and improve sustainability by adopting digital solu- tions. One area where this is particularly prevalent is the performance and maintenance of rotating equipment oper- ating in challenging locations. The ability to assess reliability and schedule mainte- nance tasks for optimum convenience can ensure minimal downtime to realise the full potential of important equip- ment. There are several options when considering rotating equipment maintenance. From the most basic ‘run it until it breaks’ theory to continuous monitoring and predictive maintenance supported by advanced algorithms and ana- lytics. Depending on the equipment in question, different approaches may be applied. Evolving strategies The simplest method is to run a machine until it stops due to a failure. This somewhat short-sighted option has very low initial maintenance costs; however, there is a significant potential for very high costs to repair the machine, includ- ing those associated with any lost production. Clearly, a more effective process would consider the wear mechanisms within the equipment and identify more frequent maintenance procedures. Worn parts should be replaced before their lifetime is reached (preventive main- tenance) to maximise the use of their wear potential while preventing component failures (see Figure 1 ). However, the lifetime of components for reciprocating compressors, such as valves and bearings, is not subject to linear wear, making it difficult to decide on the best time to replace a component based on operating hours. Maintenance decisions on components experiencing non- linear wear are challenging and cannot be made by relying solely on a time-based strategy. This process requires continuous monitoring of certain parameters that allow judgment of the components’ condi- tion and an estimation of the best time for a replacement. This is known as predictive maintenance. Focus on reciprocating compressors Reciprocating compressors have been used in many appli- cations since the 1880s, but in the past, they may not have

received the level of monitoring they deserved. Higher priority has been given to centrifugal and axial machines for a number of reasons. Firstly, the larger population of centrifugal equipment meant the focus was usually on the more prevalent machines than the reciprocating variety. Secondly, operators did not encounter significant issues due to the lower kinetic energy of these relatively slow- running machines. As a result, more recently, as the origi- nal population has aged, more focus has been required to maintain their reliability. However, reciprocating compressors are among the most critical assets in the plant. These machines can provide higher compression ratios than similar axial or centrifugal compressors. They play an essential role in many indus- tries, such as oil and gas production, refining, enhanced oil recovery, corrosive gas production, low temperature and cryogenic applications, as well as hydrogen production and petrochemical processes. In natural gas applications, they are generally part of the upstream/midstream business for wellhead gas gather- ing, vapour recovery, gas re-injection, gas lift, pipeline gas transmission, gas storage, fuel gas boosting, and boil-off gas compression. However, in the downstream segment, there is greater commercial benefit to implementing con - dition-monitoring solutions. In these processes, profit links directly to the availability of the reciprocating compressor and, as such, plants often categorise reciprocating com- pressors as critical machines.

Figure 1 Worn parts should be replaced before their lifetime is reached to maximise use

Gas 2023