Analysis & Engineering Upgrades Solve Ring Section Pump Failure

Posted on December 18, 2020

A major power plant in the United States experienced high vibration and recirculation issues with several ring section (BB4) boiler feed pumps, resulting in multiple catastrophic failures and unplanned outages. This case study details one of the pumps that was shipped to an aftermarket pump service center for a full analysis, troubleshooting, repair plan, rebuild and performance testing.

In combined-cycle plants, the demand for robust, yet expensive, barrel pumps diminished as the industry moved toward less expensive segmental rings pumps. Due to the recent shifts in the power industry, operators often face a shorter mean time between repair (MTBR), internal wear and high vibration issues on newly installed units.

After experiencing numerous boiler feed pump performance and reliability issues at their power plant, the plant owner opted to pursue a comprehensive root cause analysis and repair plan with an aftermarket pump service center in Los Angeles, California. The investigation ultimately revealed a series of underlying issues linked to the performance problems and unexpected pump failures.

Video: https://vimeo.com/452266877

Source: https://www.pumpsandsystems.com/analysis-engineering-upgrades-solve-ring-section-pump-failure

Root Cause Analysis Uncovers Casting Defects

Posted on October 31, 2019

Efficiency and reliability are at the forefront of a successful pumping system. As such, unplanned outages can be a detrimental disturbance to the overall operation. In this case, the end user’s high pressure multistage BB5 barrel pump was experiencing severe vibration, unstable performance, and failure in the field leading to unit shutdown.

This particular unit, used in boiler feedwater operations, is critical to the plant’s uptime and throughput. Furthermore, continued failures can cause growing costs due to inevitable maintenance and repairs, often overlooking a long term solution. With each unplanned outage, the plant could face a significant loss in capital.

Previously, the pump had been running for six months before experiencing catastrophic failure, requiring a shutdown and removal for further analysis. Initially, the unit’s damaged components were repaired by welding, and the volute was reassembled and installed for use. Upon its installation, the power plant placed the unit back into service but encountered a second emergency shutdown after two months in operation.

Video: https://vimeo.com/362808909

Source: https://www.pumpsandsystems.com/root-cause-analysis-uncovers-casting-defects-critical-boiler-feedwater-unit

HydroTex Deer Park Service Center Relocating to La Porte, TX

Posted on September 18, 2017

The new 33,000 square building in La Porte, Texas.

HydroTex, a subsidiary of Hydro, Inc., announces the move of its Deer Park operation to a new 33,000 square foot building in La Porte, TX.

The new service center will offer expanded capacity for analysis, engineering, rebuilding and repair services for pump systems and rotating equipment as well as climate controlled storage of pumps and parts.

Located near the busy Houston Ship Channel, the new facility is ideally situated to serve the needs of surrounding industries using pumping equipment of any capacity. To learn more about the new facility or to schedule a shop visit, please contact HydroTex.

Source: pumpsandsystems.com

Pipeline Receives Pump & Seal Improvements

Posted on November 8, 2016

Seal upgrade and pump repair in the U.S. midwest boost efficiency and reliability with minimal downtime.

Written by: Ken Babusiak, John Ciffone
Publisher: Pumps & Systems / November 2016

Mechanical seals on pumps in the oil and gas industry often need to be upgraded to meet more stringent standards, such as tighter emissions regulations. More advanced seals also offer companies increased efficiency and reliability.

Older pumps, however, sometimes need to be modified to accommodate these enhancements because the newer parts may not be the same size and shape as the ones they are replacing. In these cases, a parts supplier can partner with an aftermarket engineering firm to come up with a long-term plan for revitalizing older pumps. The refurbished pumps can offer benefits including direct cost savings and a reduction in repair and maintenance.

An Upgrade Plan Emerges

In 2011, a field service engineer was at a pipeline station for service when a technician informed him that the company was considering overhauling all of its pumps as preventive maintenance. The company planned to investigate the possibility of upgrading mechanical seals.

The field service engineer and his team decided to analyze all of the user’s pumping stations from Illinois to Iowa—about 500 miles of pipeline. Every field service engineer who worked on the pipeline met in Cedar Rapids, Iowa, where a regional engineer led a meeting about what would be the best technology solution for this user.

The team decided to replace the existing single mechanical seals with a mechanical seal developed specifically for single-seal installations and designed to attain maximum achievable controllable technology (MACT) compliance in light hydrocarbons and other volatile organic compounds (VOCs).

Image 1. The bottom half of the coupling end bearing housing installed on the pump with the bottom half of the journal bearing, oil rings and seals installed (Images courtesy of Hydro Inc.)

The field service engineers provided information on the pumps in their area, the seal data and the coupling information. All of the pumps would require minor modifications to accommodate these new seals. The team collated information about the pumps and wrote the necessary engineering projects for the preliminary drawings. Once the drawings were approved and finalized, the pumps were sent to a pump repair and service provider to be upgraded to accept the higher-technology seal.

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How Root-Cause Analysis Solved a Vertical Turbine Pump Failure

Posted on September 15, 2016

A comprehensive approach to reverse engineering helped to establish the differences between the stainless steel and original bronze impellers.

Written by: Hydro, Inc.

Publisher: Pumps & Systems / March 2016

When a severe pump failure involving one of three installed circulating water makeup pumps happened, facility personnel grew concerned about the root cause. The subject pump failed just 40 days after its commissioning.

Image 1. A crack in the discharge head flange that involved fatigue failure of the weld of a pump.

Image 2 (right). The pump’s impeller wear ring landing shows heavy scoring.

The equipment in question consisted of three-stage vertical turbine pumps running either in standalone or in parallel operation as required. The failure manifested itself through high vibration and caused severe scoring of the pump shaft and wear ring landings, leading to fatigue failure of the weld on the discharge head flange (see Images 1 and 2). The commissioned pump was refurbished and rebuilt by another company’s service center with spare impellers supplied by an original equipment manufacturer. No changes to the geometry had reportedly been made, although the impeller material had been upgraded from bronze to stainless steel.

The plant initiated its internal root-cause analysis process, and the failed pump required emergency repair. The station sought a company to conduct the repair, and the firm reviewed the customer-supplied documents and background providing the possible causes of the failure. Continue reading →