When pump systems are not optimized, it impacts a facility’s bottom line with increased maintenance, lost production and higher energy costs. System optimization is a cost-effective way to improve reliability and reduce energy consumption while improving process control to meet the process requirements. However, it is not always apparent what systems need optimization, and the expertise may not be available on staff to determine which systems need to be optimized or how to optimize them. A pump system assessment conducted by a qualified professional is the primary tool used to optimize a pumping system by identifying problematic areas where the greatest opportunities for improvement exist that will provide the greatest return on investment.
The pump system assessment process can be divided into four equally important, major tasks: pre-screening; development of the assessment team; detailed measurement, data gathering and analysis; reporting. Two more steps following the assessment are important, which are implementation of optimization recommendation, and measurement and verification.
To implement the assessment process properly, a plant needs to have a pump system optimization advocate that leads the assessment and optimization process. The advocate will communicate with management the opportunities and ensure their support, and will pull in the right plant personnel, equipment manufacturers and engineering consultants to make sure the desired outcome is achieved. Some OEMs, consulting and engineering firms offer comprehensive assessments.
The Hydraulic Institute created a Pump System Assessment Professional (PSAP) certificate program last year to test and certify individuals with extensive assessment experience.
Industrial plants can have thousands of pumps and hundreds of pumping systems, and system assessments require an investment of time and resources, so it is not wise or practical to assess all pumping systems or randomly select pumping systems for assessment. The best approach is to prescreen a plant’s pumping systems by gathering and analyzing some initial upfront information and data about a plant’s pumping system.
The prescreening determines the systems that are most in need of optimization and provides information to determine the level of assessment required to understand how to properly optimize the systems. Once the prescreening is complete, the optimization advocate has a ranked list of specific systems for further analysis that are likely to provide the most favorable return on the investment. HI offers free prescreening and modeling software tools at pumps.org/training.
Some typical prescreening data that will help prioritize opportunities include pump description, system history (unplanned failures, lost production, change in process, etc.), installed motor horsepower, yearly operational hours, control method, available instrumentation and maintenance records. The prescreening data is used to prioritize the systems with the highest operating and maintenance costs, followed by systems with known issues such as cavitation, change in duty, throttle control and frequent cycling.
From the prescreening, assessors should make a qualitative ranking of pumping systems with biggest savings potential, list the pump systems and solutions that can be implemented without detailed field analysis and list pump systems that need additional field analysis and determine the level of assessment required. Images 1 and 2 show an example of prescreening for some sample pumps. In part two of the prescreening form, there is an annual maintenance cost and annual cost of hydraulic power. Both of these provide an indication of the potential savings. These numbers—along with other system red flags—help prioritize the systems for assessment and optimization.
It is sometimes hard to justify assessments and optimization based on energy cost savings alone. Assessments are typically easier to justify by examining a combination of factors gathered during the prescreening, with unplanned failures resulting in system downtime, lost production, safety or environmental incidents, or high maintenance costs topping the list.
Once there is management approval to perform additional analysis, the assessment team will have to be developed. It is important that the assessment team have members with authority to allocate resources and coordinate logistics. The team structure should have a leader responsible for the overall outcome. This typically is the sponsor from the host organization. Moreover, qualified assessment engineers are needed in addition to specialists on system processes and functions, maintenance practice and history, and cost data.
Support of the facility management is important and the assessment should not go forward unless management supports its purpose and scope. The assessment team is responsible for communicating the business case to management when required.