Expandable fracture plug seat apparatus

摘要

An annular seat structure, for use in subterranean well stimulation operations, is operative in conjunction with associated expansion control structure to permit a predetermined number of fracture plug members to axially pass therethrough. In an illustrated embodiment thereof, the annular seat structure is movable between a retracted position having a first interior diameter, and a resiliently expanded position having a second, larger interior diameter. The seat structure has an annular array of rigid ring segments interdigitated with annular gaps that receive radially outwardly projecting portions of an annular resilient liner secured to radially inner surfaces of the rigid ring segments, the outwardly projecting liner portions being secured to circumferentially facing surfaces of the rigid ring segments. An annular spring member coaxially circumscribes the rigid ring segment array, is received in notches formed in the rigid segments, and resiliently biases the seat structure toward its retracted position.

主权项

1. Expandable fracture plug seat apparatus comprising:
an annular array of rigid ring segments having radially inner and outer surfaces and being interdigitated with an annular array of circumferential gaps radially extending between facing end surfaces of said rigid ring segments, said radially outer surfaces having notches formed therein; an annular resilient liner secured to said radially inner surfaces of said rigid ring segments; an annular spring structure coaxially circumscribing said annular array of rigid ring segments and extending through said notches in said radially outer surfaces of said rigid ring segments; and a circumferentially spaced series of resilient sections extending radially outwardly from said annular resilient liner and received in said circumferential gaps,
said fracture plug seat apparatus having (1) a retracted position in which said annular resilient liner has a first minimum interior diameter and said circumferential gaps have first circumferential widths, and (2) a resiliently expanded position in which said annular resilient liner has a second minimum interior diameter greater than said first minimum interior diameter, and said circumferential gaps have second circumferential widths greater than said first circumferential widths,said annular spring structure resiliently urging said fracture plug seat apparatus toward said retracted position thereof.