PUMPS 101
Mastering the Fundamentals of Sanitary Pumps
The keys to succeeding in a high-tech world.
Chris Sinutko | SPX FLOW, an ITT Company
From automation to AI, food and beverage processing has more tools than ever to improve safety, quality and throughput. Smart devices, remote monitoring and digital twins are helping plants make better decisions faster. Even so, the fundamentals of hygienic processing—and the consequences of getting them wrong—have not changed. Pumps and valves are central to every processing system, and getting these systems right protects consumers everywhere.
Although newer lines may be advanced, performance is still dictated by the basics: disciplined pump selection, routine maintenance and consistent adherence to hygienic practices. These fundamentals determine whether or not a facility operates reliably at its intended capacity.
The Right Pump for the Job
Not all pumps are interchangeable. The objective is to select the right pump for the application rather than forcing the process to fit the equipment. Two of the primary categories of sanitary pumps are centrifugal pumps and positive displacement (PD) pumps.
Centrifugal pumps are best for high-flow, low-viscosity applications and are well-suited for moving low-viscosity beverages through a facility. However, the design and operating point still matter. A high-efficiency centrifugal pump must maintain a stable flow profile and sufficient net positive suction head available (NPSHa) to reduce cavitation that can pit stainless steel, accelerate wear and increase contamination risk. When working with fluids that are thick, viscous or shear-sensitive or contain delicate solids, PD pumps are a good option because they deliver a more consistent, metered flow across changing system pressures.
The decisions do not stop at PD versus centrifugal. Rotary PD options such as lobe and gear designs each have distinct tradeoffs around shear, pulsation, clearances/slip and solids handling. Other PD families, including progressing cavity, air-operated diaphragm, peristaltic, reciprocating and twin-screw designs, can be appropriate depending on viscosity range, abrasive content, dosing needs, dry-run tolerance and cleanability expectations. The most effective systems evaluate the full duty points and select technology accordingly rather than assembling a patchwork of pumps to solve isolated symptoms.
| IMAGE 1: Positive displacement pumps support the backbone of key industries, including the production of soups, stews and more. (Image courtesy of SPX FLOW, an ITT Company)
The Definition of Clean
Cleaning practices and hygiene levels vary by application and the end product. What is acceptable for one product may not be sufficient for another. Cleaning is often considered the most expensive part of a plant’s operation, consuming vast amounts of water, chemicals and production time.
Driven by regulatory standards, many pump manufacturers emphasize “hygienic by design.” Common design focuses include:
- Cleanable and free-draining: Product-contact surfaces are designed for complete removal of product residuals to prevent bacterial ingress and ensure that water or product liquid drains properly and does not pool.
- Made of compatible materials: Construction materials (metal and elastomers) used must be completely compatible with the product, environment, cleaning materials and method of cleaning. Materials of construction should also be inert, nonporous and nonabsorbent.
- Smooth and accessible surfaces: All parts of the product zone should be free of pits, cracks, corrosion, recesses, open seams, gaps, lap seams, protruding ledges, inside threads, bolts, rivets and dead ends and should be readily accessible for cleaning and inspection.
The material of construction is also a selection variable for cleanability. In sanitary service, 316L stainless steel is a common baseline for corrosion resistance and cleanability; higher-alloy stainless steel options, such as AL6XN, are increasingly specified where chloride exposure, aggressive cleaning chemicals or more corrosive media increase the risk of pitting.
Upgrade decisions are typically triggered by evidence: pitting or crevice corrosion on inspection, recurring passivation, rust staining, coating failures or unusual wear marks. When these indicators appear, corrosion-resistant materials and designs that minimize crevices and support drainage often reduce the total cost of ownership despite higher initial investment.
The Evolution of Sanitary Standards
A decade ago, equipment was often categorized in two ways: sanitary or not. Today, expectations are more nuanced and increasingly shaped by risk-based thinking, validation and regulatory oversight. Proven hygienic performance has become the benchmark.
The 3-A Sanitary Standards provide widely recognized guidance for hygienic equipment design and fabrication. They establish clear, practical criteria that many processors and equipment manufacturers use as a baseline. In parallel, the European Hygienic Engineering and Design Group (EHEDG) places strong emphasis on demonstrating cleanability through validated methods and testing while allowing design flexibility when hygienic outcomes are achieved. Across the industry, traceability expectations continue to increase, and many plants are adopting more robust digital records for cleaning verification and equipment history as part of their overall quality systems.
These standards lay the groundwork for hygienic pump designs, particularly as the range of food and beverage products expands to meet diverse consumer demands.
When Hygienic Thinking Enters Industrial Spaces
A notable shift in the market is that hygienic design principles are increasingly relevant outside traditional food and beverage. In chemical and industrial processing, plants are confronting higher viscosities, more frequent changeovers and greater expectations for containment and maintainability. In parallel, materials expectations are rising as many facilities are standardizing stainless steels and higher-alloy stainless materials in places where cast iron or carbon steel were once considered sufficient, driven by corrosion resistance and the practical realities of cleaning and product changeover. In many operations, this shift is being accelerated by corrosion-driven downtime and housekeeping challenges such as leaks, rust and coating failures, all of which create safety and reliability risks in addition to maintenance costs.
While a process may require more than one pump technology, reliable seal kits across a set of sizes help streamline maintenance, reduce spare parts inventory and improve overall equipment effectiveness.
For example, a candy and protein bar manufacturer once raised concerns about their pump capabilities. At the time, they were using four different pump brands. By standardizing their transfer pumps down to one brand, one model and three sizes to handle their entire pump needs, the number of spare parts and technician maintenance needed was greatly reduced since two of the three sizes shared common spare parts.
Building Blocks for the Future
The drive toward automation and smart processing has many benefits, but it is not possible to automate a process that is not fundamentally sound. Ensuring the basics are in place, like proper pump selection and routine maintenance, is a necessary starting point and sets automated lines up for success
Chris Sinutko is vice president of product management and engineering, nutrition and health for Waukesha Cherry-Burrell at SPX FLOW, an ITT Company. For more information, visit spxflow.com.
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