Hydraulic Rerate Proven in Performance Test Lab

Custom Hydraulics for the Midstream Market

This summer, Hydro completed a hydraulic rerate project for a major US midstream pipeline. The project was completed through Hydro South, Hydro’s southeastern US service center in Alpharetta, Georgia. The project was completed with testing support from the Hydro Performance Test Lab, Hydro’s 5000 HP test facility located in Chicago, IL, with engineering direction from Hydro Global Engineering, based in Manchester, UK.

The pipeline originally used two booster pumps and the use of a Drag Reducing Agent (DRA) to achieve the desired flow rate. To increase the overall flow capacity of the line and remove the need for the DRA, the end user specified a pump to be added to the system downstream of the booster pumps.

The pump performance specifications were developed by system engineers and communicated to Hydro. The pump’s original design condition was modified to provide the necessary differential pressure required for the desired flow rate – for today and in the future. This will be achieved without the use of DRA or with little added to the system.

Hydro modified an existing pump casing provided by the pipeline and designed new impellers to meet the specific hydraulic performance requirements. Using computational fluid dynamics and advanced modeling, the new impellers were manufactured and installed by Hydro, then sent to Hydro’s test facility for hydraulic performance testing.

To provide an exact performance match, a larger impeller diameter size was selected for the first test and subsequently trimmed to meet performance within API 610 tolerances. Along with the hydraulic performance test, the mechanical integrity of the pump was measured with a vibration test, mechanical resonance test, and a bearing housing temperature stabilization test. All this information validates the quality of the rebuild and ensures a reliable machine.

The pipeline has a limited ‘budget’ of DRA concentration allowed pipeline wide. This concentration is measured in part per million (ppm). By adding the hydraulically rerated pump to the branch line, the DRA ppm budget can be allocated elsewhere in the pipeline. This will add efficiency and increase overall throughput.

Hydro is very fortunate to support critical industries like midstream pipelines in ensuring safe, reliable, and cost-effective pumps and rotating equipment.

Learn more about Hydro’s Performance Test Lab and Engineering Services

How do you measure axial thrust?

Innovations in Thrust Measurement

Thrust is an important factor in vertical turbine pumps because it directly affects the performance and reliability of the pump. Excessive axial thrust can cause the motor thrust bearing to wear faster, run at a higher temperature, and/or fail if overloaded. This results in a higher total cost of ownership by reducing equipment operating life, forcing unexpected downtime, and requiring costly emergency work.

Historically, thrust has been a calculated value based on the impeller design and other pump parameters; this calculation is an approximation and has a margin of error. Axial thrust can be more accurately assessed through testing, but direct measurement of the thrust across the profile of a pump performance curve is not typically performed by OEMs.

In support of a customers’ request to better understand the repeated failure of a vertical turbine pump, Hydro’s Test Lab and S. Himmelstein and company developed a thrustmeter that provides users with an accurate and reliable measurement of thrust across the tested performance curve. This measurement was not only more accurate than the calculated thrust values, it provided insight beyond a single operating point.

By monitoring critical pump and motor data, the end user was empowered to make the best possible decision for their equipment and plant.

Read more about this innovation in our joint white paper, published with Pumps & Systems magazine.

Learn more about how Hydro’s Certified Performance Test Lab and how Hydro can support you in better understanding and optimizing the performance of your equipment.

Corroded Steel

Fertilizer Focus: Volute Reprofiling Resolves Vane Pass Vibration

A hot potassium carbonate pump at a nitrogen fertilizer plant had been experiencing elevated vibration at vane pass frequency. Recognizing that this vibration likely contributed to shortened equipment life, the end user partnered with Hydro to investigate the root cause of the vibration and modify the pump as necessary to remove it.

When the vibration and performance indicated that it was time to take the pump out of service for refurbishment, it was sent to Hydro’s Chicago service center for inspection and analysis. The inspection showed significant damage caused by component contact and erosion.

After reviewing the inspection data, an engineering analysis was completed on the design to determine what could be done to eliminate the vibration. The engineering team determined that the vane pass vibration was related to shock waves caused by the high energy fluid impacting the volute lip. This was intensified in the first stage, where the 4-vane impeller was discharging into a dual volute. The volute lip was reprofiled to reduce this impact and provide a smoother transition from the impeller exit into the volute passage.

The upgraded design was tested in Hydro’s performance test lab. This gave the end user confidence that the hydraulic performance of the pump had not been negatively affected by the volute lip geometry modification. It also verified that the vibration amplitudes had been reduced. After successful testing, the modified pump was returned to the field, where it continues to run smoothly.

chart, bar chart

1. Reduced Vane Pass Vibration Observed During Testing

Casing Geometry

Fertilizer Focus: Expedited Sourcing for Replacement Casing

A Midwest US fertilizer plant had a boiler feed pump whose casing suffered from significant erosion damage at the packing gland location. The damage to the casing was severe enough that it was unusable. The delivery time and cost for a new pump both exceeded what the plant felt comfortable with, so they looked for alternative means to return the pump to reliable operation.

To provide a solution that reduced cost and lead time, Hydro’s Chicago service center explored various outlets for a used casing that could be refurbished for the service. Fortunately, a casing that matched the original boiler feed pump’s size and number of stages was found and procured.

Understanding the importance of casing geometry for hydraulic and mechanical performance, Hydro’s engineering team performed an extensive analysis of the two cases to verify geometric equivalency. After the engineering analysis concluded that the used case would meet the required hydraulic performance, it was refurbished and brought up to best-in-class tolerances.

Boiler feed pump casing

As a final check to ensure that the refurbished case would operate smoothly and achieve the desired performance, the newly assembled pump was tested at Hydro’s performance test lab. The test lab generated a full performance curve that verified that the pump met the design operating flow and head. Mechanical performance was also assessed to ensure that vibration was acceptable throughout the operating range.

By reusing an old casing instead of purchasing a new pump, the site was able to reduce the cost of the repair. More importantly, the repair was completed in a much shorter timeframe than it would have taken to source a new pump. This greatly reduced the risk to plant production of not having a spare pump available on-site.

 

diagram, engineering drawing

Wireless Sensor Data Integration Into Existing Plant Historian

A large American energy company wanted a new data collection system to be integrated into its site historian along with process trending software to better diagnose system-related issues that can lead to maintenance issues.

Thanks to the help of an aftermarket service company, the energy company combined multiple sources of data and can now view complex mechanical vibration phenomena in parallel with plant process data. By comparing the two sets of data side by side, plant personnel will correlate process conditions with mechanical vibration data.

The service provider’s history of pump and rotating equipment knowledge helped to provide actionable analysis of pumps and other rotating equipment health—and a mechanism to provide additional engineering solutions to complex problems. Combined with the energy company’s focus on reliability and a history of maintaining their equipment, this system provided an improved method of data collection and analysis.

Source: https://www.pumpsandsystems.com/wireless-sensor-data-integration-existing-plant-historian