US 5,176,208 A · Reverse circulation tool handling cuttings and debris

Abstract

A device for providing fluid cross over in a milling operation is set forth. It is particularly used by connection to a pipe string which supports the milling device for cutting junk from a well. It features an elongate hollow tool body having a central portion which defines a trash receiving chamber. There is a pipe inserted into this chamber from below for introducing return fluid after cutting which is laden with metal shavings, chips, and trash. In this chamber, fluid flows upwardly through the pipe, and trash collects in the chamber by surrounding the pipe falling to the bottom of the chamber by weight. The chamber is limited at the top end by transverse wall which has a number of perforations having an aggregate cross sectional area to prevent fluid flow restriction. Fluid flow cross over is accomplished whereby new fluid is introduced through the pipe string, flows to the exterior below a rubber pack off, flushes the cuttings downwardly and away from the milling device, and returns the fluid up through the tool where trash in the fluid is captured.

Claims17

Dependent claims

A reverse circulation tool connected to pipe string for operation of a milling device, comprising:

(a) an elongate hollow tool body having upper and lower ends and having an axially aligned central passage in the upper portion thereof which a pipe string fluid circulation is directed;
(b) externally directed port means located below an externally located resilient pack off wherein said port means is connected to said passage to direct fluid flow from the passage into an annular flow space around said tool body to flow downwardly to lubricate a milling device connected below said tool body;
(c) an internally located, upwardly directed fluid flow, trash receiving passage extending upwardly from the lower end of said tool body;
(d) an elongate trash receiving chamber in said tool body connected with said trash receiving passage to enable fluid flow and trash from the milling device to enter said chamber and to also collect such trash in said chamber;
and
(e) a fluid removing passage from said chamber connected for fluid removal from said trash receiving chamber wherein said passage extends through said tool body to an outlet port to exhaust fluid from said tool body into an annular flow space around said tool body above said port means to return fluid along the pipe string.

3 more elements

Dependencies are inferred from the claim text.

Reverse circulation tool handling cuttings and debris

Life of this patent

Reverse circulation tool handling cuttings and debris

Life of this patent

Abstract

Claims17