Patent ID: 8763987
Filing Date: 2014-07-01
Classification: F16K,Y10T

Abstract:
1. A butterfly valve comprising: a valve body including a valve opening; and a flapper rotatably mounted within the valve body about a rotation axis so as to be rotatable to any desired valve opening amount between and including either of two possible angular positions that are 180 degrees apart; a flapper positioner having a configuration that, in response to a command to rotate the flapper to a desired angular position, can rotate the flapper to the desired angular position; and a flapper controller having a configuration that causes the flapper controller to: receive a command to move the flapper to a desired valve opening amount; and for each desired valve opening amount: determine by measuring valve slip which of the two possible angular positions that are 180 apart for that desired valve opening amount the flapper should be positioned based on a goal of cleaning deposited debris from the flapper and the valve body; and command the valve positioner to rotate the flapper to the determined angular position.