Unibody bypass plunger with integral dart valve cage

Abstract

A bypass plunger formed as an integral one-piece hollow body-and-valve cage unit retains a dart valve within a valve cage section of the hollow body with a threaded retaining nut that may be secured by crimple means. A boundary zone, defined along the plunger body, where the integral valve cage section adjoins the plunger body, is configured with a uniform outer diameter to maximize the plunger body wall thickness and durability of the one-piece bypass plunger. The valve cage may have flow ports configured with ramps at an angle with the longitudinal axis to control flow through the flow ports during descent of the bypass plunger. A clutch assembly using garter springs with split bobbins may be disposed within the valve cage portion of the one-piece bypass plunger.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]The present Application is a continuation-in-part of U.S. patent application Ser. No. 16 / 130,635, which was filed on Sep. 13, 2018, the content of which is incorporated herein by reference. This application is also related to U.S. patent application Ser. No. 14 / 796,548 filed Jul. 10, 2015 by the same inventors and entitled BYPASS PLUNGER, now U.S. Pat. No. 9,951,591 issued Apr. 24, 2018 incorporated herein by reference; and also related to U.S. patent application Ser. No. 15 / 048,467 filed Feb. 19, 2016 by the same inventors and entitled CLUTCH ASSEMBLY FOR BYPASS PLUNGERS, now U.S. Pat. No. 9,963,957 issued May 8, 2018 incorporated herein by reference; and also related to U.S. patent application Ser. No. 15 / 048,491 filed Feb. 19, 2016 by the same inventors and entitled and DART VALVES FOR BYPASS PLUNGERS, now U.S. Pat. No. 10,273,789 issued Apr. 30, 2019 incorporated herein by reference. Any provisional application cited in the above rela...

AI Technical Summary

Benefits of technology

The patent text is describing a design for a valve that prevents the one-piece tubular plunger from cracking under severe impact. This is achieved by using a thick tubular body and a boundary zone with the same outer diameter as the main body. This design ensures that the valve can withstand high levels of stress and maintain its integrity.

Problems solved by technology

Each ‘garter’ spring is wrapped around its groove and the ends crimped together, typically in a hand operation that is subject to some variability in the tension around the bobbin halves and possible failure of the crimped joint, which could affect the reliability of the clutch when in a downhole environment.

While generally effective in lifting accumulated fluids and gas of unproductive wells such conventional bypass plungers tend to be complex and suffer from reliability problems in an environment that subjects them to high impact forces, very caustic fluid, elevated temperatures and the like.

However, failures remain common, and a substantial need exists to eliminate the causes of these failures.

Images