Minimum continuous stable flow
Minimum continuous stable flow (MCSF) refers to the lowest flow rate (GPM) at
which a pump can operate continuously without exceeding the vibration and/or
noise limits specified by a user who may be represented by a purchasing agent,
an engineering contractor, or a consultant.
In setting these limits the customer usually refers to a widely accepted industry
standards, such as ANSI, API, ISO, ASME, or in some cases to the customer's
own pump specifications.
If, for example, a customer specified an API pump, then the pump should comply
with the vibration and noise limits set forth in API 610 standard. The vibration and
noise limits are imposed to ensure the design integrity of the pump, improve its
reliability, (or its mean-time- between-failures (MTBF) and, at times, to comply with
environmental regulations with regard to noise abatement.
If a pump were to operate below the manufacturer's recommended minimum
continuous stable flow, it may be necessary to provide a low flow by-pass line to
recirculate part of the flow equal to the difference between the MCSF and the
lowest flow rate at which the user will operate the run.
There are many ways by which a manufacturer determines its recommended
MCSF for a specific pump - based on test results, historical experience, or the
specific hydraulics that go into the pump design. The characteristics of the
pumped liquid, as well as the energy density of the pump, are also taken into
Categority: design, operation, trouble-shooting
File: flow stable