Articles about Split Flow™

U.S. Patent Office issues patent for ‘Big’ Split Flow™

The United States Patent Office has issued the patent for the 2015 edition of Split Flow — an innovative API centrifugal pump that employs two different impellers in the same pump casing. The new Split Flow applies to both overhung and between bearing pumps. The new patent is a substantial upgrade from the original, 1997 version of Split Flow, which only covered overhung pumps.

Big Split Flow™

This Split Flow application involves a two-stage, API between-bearings centrifugal pump. This design features a radially split centerline-mounted case designed for high-temperature (up to 800°F) hydrocarbon service. The Split Flow feature precludes the need for two separate pumps and saves energy when one pump is used for two separate process flowstreams. The pump is effectively two pumps in one.

The basics of the new Split Flow™

Essential facts, specifications and parameters of the new Split Flow patent.

Little Split Flow™

The Split Flow patent applied to a single-stage, API overhung centrifugal process pump — either horizontal or vertical inline. The Split Flow feature incorporates a low-flow auxiliary impeller which receives inlet liquid from the discharge of the primary impeller. The Split Flow feature allows the economy of combining two separate pumps into one. See Little Split Flow design configuration options.

Split Flow facts and applications

When process designs use API Standard 610 centrifugal pumps for Dual-Service applications, use of the Split Flow™ feature provides unique benefits, detailed here.

Split Flow process pumps save energy

Application for U.S. Department of Energy National Industrial Competitiveness Through Energy, Environment, and Economics (Nice 3) Program. Includes many important Split Flow facts.

Carbon dioxide reductions

The efficiency of the Split Flow application saves energy, and thus reduces carbon emissions — anywhere from 233 to 433 metric tonnes of CO2 per year.

The Split Flow™ option

Engineers in every discipline need to be alert for opportunities to save capital and reduce operating costs. The Split Flow™ option is a new way of reducing operating and capital costs for auxiliary systems.

Process engineering assessments

Split Flow provides cost-saving option to common process problem.

Summary comparison of Big and Little Split Flow features

Split Flow displays and comparisons

Typical pump services with crude atmospheric distillation tower

API Standard 610 and overhung pumps

The API 610 Taskforce has noted that the two-impeller design for dual service "...has a niche where it is desirable and does not want to discourage its application by inclusion."

Minimum flow bypass

Use of the Split Flow feature with process pumps allows the specified operating range to be closer to BEP (best efficiency point), as recommended by the API Standard 610 hydraulic fit criteria. This optimized pump-to-system fit reduces the pump's minimum flow and simplifies turndown control.