Definition of Duty-Factor
The duty-factor of your pump or system could simply be the product life. Or the duty-factor could be more specifically defined as the length of time a pump or system runs between servicing and the type of performance during this time frame.
Elements determining Duty-Factor
The duty-factor is affected by many variables including operating time, application, design, installation, system components and various operating and maintenance costs.
As the demands on the pump or system increase, so can the duty-factor. Does the pump or system run 24 hours per day, 365 days per year? Is it operating at intermittent duty for 2-3 hours per day, 3-4 days a week? Is it operating only at light duty for 2-3 hours, once a month or for 2-3 months per year?
The application is very critical in determining the duty-factor. Is the pump or system pumping fresh water, mild soaps or sanitizers? Is the pump or system required to pump harsh seawater, chemicals or wastewater? Is the pump or system needed for high temperature or low lubricity liquids? Will the pump or system require suction feed, long feed lines or present other stressful conditions?
Has the pump or system been designed for continuous-duty, intermittent-duty or light-duty? Is the pump and other system components constructed of materials compatible with the liquids being pumped? Is the pump held to close tolerances, quality testing and intended for the type of application?
Installation & System Components
Is the proper plumbing used in the system? Are the proper safety devices installed? Is the power source adequate for the flow and pressure of the system and has the drive been properly installed? Is there adequate voltage for the electric motor? Do all accessories have comparable specifications and duty-factors as the pump? Is the system providing for adequate inlet supply to the pump? Are there temperature sensors to detect overheating or low flow shut-off switches to prevent starving the pump?
Costs relating to Duty-Factor
How often does the product need servicing? Do you have a trained technician available to work on your system or will you need to invest in training? Is the product easy to service or does it require considerable downtime and special tools? How much is production or service interrupted, if the system should go down? Are parts readily available? Is your pump energy efficient?
Products that look-a-like, but have different costs are not always what they seem. Comparing individual pumps or a complete systems, may only look-a-like to the unfamiliar viewer. Materials of construction, tolerances in manufacturing, design functionality of the product, previous experience in the application and the duty-factor all affect the cost of the product. Most important, the purchaser should not consider the cost of equipment alone, but operating costs plus purchasing cost, to determine the true value of the product.
Those products with the quality materials, high manufacturing tolerances, product testing and field proven performance should be your selection for the continuous-duty applications, while products with lesser quality and performance ratings may be adequate for the light-duty applications.
Typically, consumer, commercial and industrial systems do not look-a-like and do not have the same level of quality components or duty-factor.
Duty Factor Rating System
The best rating system is determined by historical data, customer testimonials, field proven results and market share of product. Customer confidence and user satisfaction is reflected in the numbers of that product in use. Heavy-duty applications require dependable pumps and systems. Dependable products are those that have proven to operate successfully over time. Confidence comes from a manufacturer who has continually introduced products with a consistent quality and a dependable performance record.
Products should be carefully marketed to the intended end user with the industry, application and duty-cycle the main criteria. Participation in trade shows and advertising in media that focus on the products' intended market, application and duty-cycle will assure a better product fit. Selecting a product that is properly supported with technical manuals and product literature help assure proper installation, operation and maintenance and will provide the best duty-factor. A supplier with a well informed technical staff to ask the correct questions at the first inquiry will also assure a proper product fit and better duty-factor.
How Quality affects the Duty Factor
Typically when a system is designed around a high quality pump, all the components in the system are high quality. This promotes long life, minimum maintenance and low service costs. In a heavy-duty use application, the high quality and low duty-factor are more important, while in a light-duty use application, the higher duty-factor may not be as significant a concern.
Sometimes not all aspects of the system or application are initially known or carefully considered. Improvements to the pump or system can be made to improve the duty-factor. Upgrading a component in the system or making modifications to a component can improve the duty-factor. In pressure cleaning equipment, a higher quality pump can be substituted to improve the duty-factor. In a high quality system, modifications such as a secondary safety devise, temperature protectors, auto-shut-off devices or special pump seals and o-rings can further improve the duty-factor.
Levels of Duty Factors
Pressure Cleaners have basically three levels: consumer [light duty], commercial [intermittent duty] and industrial [heavy duty]. It is important to assess the type of task being done, the time required to complete the task and the frequency or repetitiveness of the task before selecting the pressure cleaner for your application. And, most importantly, do not select your pressure cleaner on initial purchase cost alone.