ANSI process pumps are the only pumps in the United States that are dimensionally standard as deemed by the American National Standards Institute (ANSI). By definition, these centrifugal pumps are horizontal, end suction, single stage pumps that are comparable in size and identical in interface and envelope dimensions, regardless of manufacturer. The pumps are also required to meet ANSI B73.1 standards, also known as ASME B73.1 and have a number of uses.

What is ASME B73.1?

This American Society of Mechanical Engineers (ASME) standard covers process pumps of horizontal, end suction, single stage, and centerline discharge design. Pumps must meet dimensional interchangeability requirements and contain special features for installation and maintenance. The purpose of the standard is to ensure that other ANSI process pumps with similar sizes can be interchangeable in size of suction, location of suction, discharge nozzles, baseplates, input shafts, foundation bolt holes, and mounting dimensions.

There is a similar standard called ASME B73.1-2012 which also covers horizontal end suction centrifugal pumps for chemical process. It covers metallic and solid polymer pumps and is designed to facilitate installation and maintenance, as well as to enhance the safety and durability of ANSI B73.1 pumps.

ANSI Process Pump Applications

ANSI process pumps conform across manufacturers and allow the buyer to switch pumps and brands without having to change or redesign motor attachment, coupling, piping location, or bedplate dimensions. This ANSI process pump sizing standard is broken down into three main groups.

• Group I covers ANSI process pump sizes from 1.5 by 1-6 to 3.0 by 1.5-8.
• Group II covers ANSI process pump sizes from 3 by 2-8 to 6 by 4-13.
• Group III covers ANSI process pump sizes from 6 by 4-16 to 10 by 8-17.

This pump comes in a wide range of materials, including alloys and non-metals for many corrosive services, depending on the application. Although mostly used in the chemical industry, ANSI process pumps are also used in food processing, paper mills, pulp mills, refineries, ethanol production, textiles, and various other process plant applications.

Number wise, ANSI process pumps have flow rate ranges between 10 to 5,000 gallons per minute, or 38 to 18,927 liters per minute. The total head pressure ranges from 50 to 750 feet (22 to 325 psi), and horsepower from 1.0 all the way up to 250.

Pro’s and Con’s of ANSI Process Pumps

Given the end suction and centrifugal design of ANSI process pumps, they are ideal for transferring water and mostly thin liquids. The pumps can also move liquids with or without solids based on their impeller type. However, the design does not typically allow the pumps to move thicker liquids, such as oils. In addition, ANSI pumps only meet one standard so they are difficult or not feasible as replacements for other types of centrifugal pumps.

Advances in ANSI Process Pumps

Griswold’s 811 ANSI Process Pumps – In addition to traditional applications, this line of ANSI pumps can also be used in the water and wastewater market, such as water parks, commercial swimming pools, water treatment, HVAC systems, and many others. These pumps also perform beyond standard metrics and offer a max flow capacity to 7,500 gpm, total head to 920 feet, and can even accommodate fluid temperatures up to 500 degrees F.

Enviropump and Seal VIT-1000 Series “Super-ANSI” Process Pump – VIT pumps were developed to remedy the shortcomings of traditional ANSI pumps and their tendency to fail in bearings and mechanical seals. The VIT 1000 pump is made with non-metallic labyrinth oil seals, rugged ductile iron bearing frame with cast-in cooling fins, and mechanical seals with “double-balanced” O-ring design, among many other features to ensure a low life cycle cost.

For More on ANSI Process Pumps

Below are some of our favorite resources for ANSI process pumps:

ANSI Centrifugal Pumps Offer Speed and Reliability in Oil & Gas Operations – Gary Israel of Griswold Pump discusses how ANSI pumps can go beyond the expected chemical process applications and into the world of oil and gas as reliable equipment.

Specification for Horizontal End Suction Centrifugal Pumps for Chemical Process – Download this print or digital book from the ASME to learn more about its ASME B73.1-2012 standard for $49. They also offer a free data sheet on the ASME B73.

NGWA Seeks ANSI Standard For Pumping Systems – Ever wonder what’s next in ANSI standards? This article for Water Online discusses the need for a consensus body for developing a groundwater pumping systems standard to include guidance on performance requirements for pumps used in water wells.