Sand Cleaner

Introduction

The sand cleaner is designed to prevent exploiting formation and remove existing debris efficiently especially in horizontal wells, deviated wells and extended reach wells. The tool can eliminate the risk of sticking of strings caused by debris sedimentation or aggregation at deflecting and horizontal sections in complex structural wells. It helps preventing accidents in down hole and ensures drilling operations on the rails.

Application 

In cutting bed well sections, the most efficient way to clean well bore is to use sand cleaner during drilling. When drilling fluids come back through sand cleaner, it will produce a radial shunt to mud cake as a liquid brush which changes the fluid energy into the traction force by changing the fluid direction. The tool can destroy the debris, make the cuttings suspended, and facilitate the drilling fluid to carry sand out. The sand cleaner will greatly reduce the flow resistance of bottom hole, clean the bottom and greatly enhance the cleaning efficiency.

It is usually installed with intervals of 90~150m among drilling strings. In each well, it shall apply with enough sand cleaner in BHA and install above the string with maximum OD. In practical operation, it is mostly installed as per drilling experiences. 

Without Sand Cleaner                                                             With Sand Cleaner

  Less Debris                                                                           More Debris

Function & Working Principle

- It prevents debris from sedimenting.

  “V” flow can stir and excavate the debris at cutting bed, bring the debris to “V” groove from low speed section to high speed section, and make the sedimented cuttings suspend again.

- “V” flow has larger flow area and with an increased flow rate it can produce stronger cleaning force on surrounding cuttings.

-  Specially designed structure can crush the debris making the big cuttings into small cuttings for easier carrying out.

-  “V” flow plays a guiding role for incoming flow, the combination of changes on direction and speed of incoming flow increases turbulence of liquids around BHA. From drilling hydraulics point of view, it is very useful for carrying and cleaning debris.

Features and Advantages

- It is an integral piece without any movable parts, and its strength is higher than drill pipe which to be connected with it.

- It applies both hydraulic and mechanical force to destroy and clean cutting beds.

- Carbides are inserted on the surface of “V” flow to improve abrasion performance.

Specification

The main specifications are mentioned in below.