Midstream companies traditionally have built a few compressor stations a year with periodic upgrades to implement new instrumentation technology, increase compression horsepower or improve control systems. New and upgraded facilities were few and relatively easy to complete with a minimum of skilled in-house design and engineering personnel.
With the recent boom in the natural gas industry through the development of high-tech horizontal drilling into the gas shale plays in the Northeast, Midwest and Southwest areas of the U.S., companies now need multiple compressor stations to keep up with increased natural gas supply. Instead of a few new compressor stations every year or two, multiple compressor stations have become the new norm for many companies.
With the growing demand for new compressor stations, it is no longer economically feasible to provide an individual design for each new compressor station. Schedules have been shortened and consistent quality has sometimes been sacrificed due to a lack of qualified construction crews. Construction schedules have been extended, and as experienced and qualified contractors become busier, the development of complete, high-quality compressor station design packages critical for consistent quality compressor station installations have become more difficult to achieve.
Clearly, standardization is becoming the new norm for a very good reason: It adds value. Specifically, it creates value in three ways:
First, capital expense reduction, mainly due to repeat engineering, volume contracts with preferred suppliers, discounts for material, and services and integration efficiency.
Second, standardization enables project engineers to use proven designs and avoid "re-inventing the wheel." Standardization results in reduced FEED effort requirements, fewer mistakes and increased productivity, which in turn results in reduced cycle time, which in turn helps accelerate cash flow from operations.
Third, value is created through reduced operating expenses for subsequent projects. This is mainly due to increased start-up efficiency, improved uptime, and commonality of equipment and training.
CDI Corporation’s Oil, Gas & Chemicals business currently is in the process of helping a large natural gas midstream company to develop compressor station facility standards. As we develop standardized facilities for any of our clients, we establish a few key goals at the outset:
- Quick preparation of construction bid packages. Process and instrumentation drawings, piping standards, equipment packages, layout drawings, foundation details, control panel hook-ups, automation and electrical loops, and bill of materials are pre-prepared and pre-approved, resulting in a minimum of preparation time from the initial bid package to commissioning of the system.
- Timely proposal responses from qualified construction companies. Layout and construction schedules are reviewed, pre-checked and approved by qualified construction personnel to take into account the scope of work, schedule, construction sequencing and layout.
- Consistent construction and installation quality. Standardized materials, complete bill of materials, standardized pre-purchase of materials and consistent material stocking by the client allows the contractor to build a station quickly with a minimum supply of material.
Optimized site layout. This enables ease of accessibility for construction, maintenance and service.
Standardization of components throughout the midstream system. This allows the client to duplicate systems, thus minimizing spare parts inventory.
- Total yearly component counts. These are provided to optimize component bid package preparation inquiries and purchases for quantity discounts.
A critical step in CDI’s approach to value-based standardization is the balanced and complementary application of two seemingly competing design paradigms: standardization and flexibility.
Our initial evaluation of a client’s project begins with a comprehensive assessment of the client’s past and future development/expansion plans as well as the inherent range of operating and production conditions they expect to encounter. Through this exploratory process, we determine the components and systems that should be standardized and identify the most efficient design options. This deep-dive approach allows our clients to fully recognize the potential benefits as well as the trade-offs that standardization offers.
This approach also helps CDI and the client establish criteria for screening alternative future standardization design parameters that will be used to guide optimal design iterations throughout the standardization program.
Typical design criteria boundaries established through the collaborative process include but are not limited to:
- Environmental Operating conditions
- Current & Future route locations and demographics
- Current & future commodity composition, assay and volume
- Present installed asset base and/or past facility design and layout
- Flow rates, suction and discharge pressures
- Preference of specific or desired equipment
Once design criteria boundaries have been established, CDI works closely with clients to establish metrics to measure the efficacy of the standardization program.
On a recent project, design criteria boundaries were grouped into distinct compression size types with variations stemming from volume and suction pressures. Each subsequent design allowed enough flexibility to accommodate the unique operating production environment that was established at the outset.
Another benefit of establishing design criteria boundaries is the automation of design iterations and modularization via advanced 3D computer-aided graphic design software. Once the "base" station models exist, CDI’s experienced engineers and designers can create many different iterations to ensure the most efficient and economical design.
Through an integrated systems approach and by leveraging CDI’s engineering experience and expertise, standardization can achieve a significantly faster time to market for our clients.
In conclusion, the standardized design of compressor stations allows midstream companies to provide a design template for many similar-sized compressor stations.. That template can be "tuned" for location-specific needs but otherwise it allows companies to utilize the best technology, design and construction methods on a consistent basis. It provides a quick response to new compression system requirements, minimizing in-house engineering time, while providing a high quality, consistent package each time a new station is placed in service.