Case Study- Solving Vibration Issues in Vertical Pumps

Vertical pumps are especially susceptible to minor conditions that can result in elevated vibration amplitudes. The vertically suspended design and long stationary element lengths often combine into natural frequencies that are near forcing frequencies, such as running speed or even sub-synchronous faults. The complexity of these issues makes it difficult to diagnose and resolve persistent vibration issues with the type of data that is routinely available to the end users.

In-depth field testing paired with computational analysis provides a clear path to both an accurate diagnosis and a solution that has a high likelihood of success. The effectiveness of this methodology was proven for a Gulf Coast midstream company who was experiencing high vibration with their vertical freshwater pumps. By applying advanced field diagnostics, the end user was able to understand the underlying causes of the vibration and evaluate possible solutions in a theoretical environment prior to implementing them in the field.

Read the full case study, published in the May 2025 edition of Pumps & Systems magazine, here.

Read more case studies on vibration analysis and the work completed by Hydro Reliability Services here.

Byron Jackson Process Water Pump Improvements

Application: Pond Process Water
Pump Details: Byron Jackson 32KXL
Pump Type: Multi-Stage Vertical

Industrial pumps are sometimes repaired or modified by smaller local repair shops that do not have the engineering oversight to ensure that the repairs and modifications meet the original design’s intent. When Hydro received this pump, it was clear that prior modifications that had been performed without engineering review were causing problems.

This pump had been “upgraded” by replacing the upper bearing with an enclosure tube, which was not part of the original design. The lack of that bearing contributed to the instability of the top shaft and may have lead to the pump’s failure.

After fully reverse engineering the pump, Hydro redesigned the existing enclosure tube to incorporate the missing upper bearing. The modification involved machining the enclosure tube into two pieces and joining them together with a coupling and adding a bushing to stabilize the shaft.

Because the spare parts provided were of an older design and no longer fit the pump, Hydro manufactured several parts. These included a new transition piece, diffusers, a new bearing, and suction bell. Moreover, the impeller vane tips were weld-repaired and re-machined, and the impellers were then balanced to 4 W/N. The pump, which was rebuilt to standard specifications and reconstructed using a durable stainless steel, was returned to service successfully.

Learn more about Hydro’s targeted upgrades for the pulp and paper industry here.

Lear more about Hydro’s Scotford service center, the service center that spearheaded this project, here.

Innovative Vertical Pump Sealing Solutions

Upgrade in Action: HydroSeal 

Vertical pumps have reliability and maintenance considerations unique to their design and application. One of these considerations is the pump seal design. Many vertical pumps rely on packing in lieu of mechanical seals. While it is a less sophisticated design, packing has benefits for vertical pumps, including greater ability to handle fluid with particulates, less sensitivity to misalignment, and greater stiffness and damping provided at the seal location. However, packing also has multiple disadvantages, foremost of which is the need to continuously adjust the packing gland to maintain the desired leakage rate and the requirement that some fluid must leak to the atmosphere. The cost associated with replacing worn components in the packing area is another notable drawback.

 

In cases where any of the disadvantages associated with packing or a mechanical seal noticeably impact reliability or the cost of operation, upgrading to a seal casing design is an attractive alternative. This is the decision that a pulp and paper mill in the Southeastern US made when experiencing reliability and environmental concerns in their River Water pump system. Faced with the need to install a new sealing device, they decided that the ability to avoid aboveground leakage and eliminate time-consuming periodic maintenance justified the investment in a vertical pump seal casing.

Read the full case study in World Pumps March/April 2024 edition.

Learn more about Hydro’s Hydro South service center and Hydro’s Engineering Services.

In-Person Vertical Pump Fundamentals (Seminar)

Join Evans Hydro for an in-person seminar on Vertical Pump Fundamentals hosted at our service center in Rancho Dominguez, CA.

What You Will Learn:
  • Common pump applications and operating characteristics
  • Basic hydraulic characteristics
  • Vertical turbine pump assembly and maintenance tips
  • What to look for in a failure and how to apply corrective actions
What You Will Earn:
  • Five (5) CWEA Contact Hours
  • Critical knowledge on how to improve pump reliability and life
 Who Should Attend:
  • Maintenance Supervisors
  • Maintenance Foreman
  • Mechanics
  • Anyone involved in the operation or maintenance of pumping equipment and systems.

Register Now