Sulzer adaptability provides boost to energy provider

When a major energy provider needed a 21-day turnaround on the repair of two high speed boiler feed pumps they turned to Sulzer, whose professionalism and adaptability ensured a successful outcome.

The equipment owner presented a very detailed repair specification that was to be followed precisely. Some of the challenges with this particular style of pump included developing clear and precise inspection templates, instructing and reviewing with the shop personnel where and how to inspect the critical fits and recording the required information to meet the customer’s inspection criteria on the initial inspection.

Sulzer provide a thorough inspection

One of the first requirements was a special cleaning procedure that the service centre managing the repair was not equipped to do. However, by using the other Sulzer facilities located nearby to accommodate the demand, the cleaning procedure was quickly completed without incurring any delays. Once complete, the pumps were returned to the original Sulzer site to begin disassembly.

Inspection of the individual components determined that some of the impellers were damaged and were deemed irreparable. The hub side plates on at least half of the series impellers were cracked through and required replacement. This level of damage had not been planned for and replacement components are not typically stored by either the customer or the manufacturer.

3D model completed within one week

Having advised the customer of the unexpected discovery, inquiries were made with the OEM about the best lead time for new impellers, which came back as 20 weeks. Sulzer was able to offer a full set of new components, available in just five weeks, an offer that the client gladly accepted.

The damaged impellers were sent to one of Sulzer’s manufacturing centres, which has full reverse engineering and design capability for both hydraulic and mechanical components. The design team offered the client an opportunity to improve the performance characteristics of the impellers using the latest design and manufacturing techniques, but this was declined.

A 3D design of the original impeller was created using coordinate measuring machines (CMMs), which allow on-site data acquisition quickly. These machines gather three-dimensional data and allow the obtained dimensions to be repeatable to within 0.001". The 3D model was completed within one week and the data immediately transferred to the engineering and manufacturing departments where the new designs could start to take shape.

Sulzer delivers true turnkey solution

However, with such extensive and unexpected damage, meeting the original program deadline of three weeks was going to be impossible to achieve. Following discussions with the client, Sulzer proposed to rebuild one of the pumps using the best components from both pumps. This required moving diaphragms and diffusers between the pumps and correcting all the fits and clearances in order to achieve the required design specifications.

The first pump was completed and returned to the customer one day early, while the second pump was completed and shipped back to the customer on schedule in order to meet the operational requirements of the plant. The team approach displayed in this type of project enables Sulzer to deliver a true turnkey solution and maintain clear communications by operating through a single point of contact. In this way the client remains fully appraised of progress and is able to make informed decisions when unexpected circumstances arise.

Repair specialists need skills and adaptability

In today’s world of large scale pump maintenance, it is essential for repair specialists to have a wide range of skills and adaptability in order to deliver a comprehensive service. Equipment is becoming more complex and the facilities required to maintain them, more expensive.

Although technology has evolved since much of the equipment in the power generation sector was manufactured, it is possible, with the right engineering expertise, to improve reliability and efficiency by remanufacturing certain components as part of the regular maintenance program. In the long term, this helps to improve productivity and reduce the likelihood of unexpected breakdowns.