What is the Casing Brush?

A casing brush used in drilling and well completion is a robust downhole tool designed to clean the interior of casing strings before or after cementing, perforating, or logging operations. It ensures smooth casing walls by removing rust, scale, cement residue, and other debris that could obstruct tools or reduce well productivity.

Key Features of a Drilling Casing Brush:

1.Heavy-Duty Construction

Made of high-strength steel or non-sparking brass/bronze for hazardous zones.

Stiff wire bristles (sometimes replaceable) for aggressive cleaning.

2.Threaded Connections

API-standard threads (e.g., API Reg Pin x Box) for easy attachment to drill pipe, tubing, or wireline.

3.Adjustable Diameter

Some brushes have spring-loaded bristles to accommodate slight casing ID variations.

4.Centralizers

Optional stabilizers to keep the brush centered in the casing for even cleaning.

Primary Applications in Drilling & Well Workovers

1.Pre-Cementing Cleaning

Removes mud, scale, or rust to ensure a strong cement bond.

2.Post-Cementing Cleanout

Cleans excess cement (“wiper brushes”) after casing cementing.

3.Before Perforating/Logging

Ensures guns or logging tools run smoothly without debris interference.

4.Scale & Paraffin Removal

Used in production wells to clear mineral deposits or wax buildup.

Types of Casing Brushes for Drilling

How It’s Run in the Well

1.On Drill Pipe/Tubing: Rotated and reciprocated for scrubbing action.

2.On Wireline: Used with a jarring tool for vertical wells.

3.With Fluids: Often combined with circulated solvents or acids for tough deposits.

Sizing Considerations

Brush OD should be 1/4″ to 1/2″ larger than casing ID for effective scrubbing.

Example: For 7″ casing (6.276″ ID), use a 6.5″–6.75″ OD brush.

Junnie Liu

Mobile/Whatsapp:+0086-158 7765 8727
Email: landrill@landrilltools.com