Free Drill-Out Stage Collar for Oil & Gas Cementing

The Free Drill-Out Stage Collar is a downhole cementing stage tool designed for staged cementing in oil and gas well completion. This tool features a gravity-activated free drill-out opening mechanism, which eliminates the need for conventional drill-out operations after the cementing process, making it particularly suitable for vertical wells.

Stage collars are integral in staged cementing operations and provide an intermediate passage in the casing string to enable cement displacement for specific intervals. They allow controlled opening and closing of ports so that cement can be pumped in multiple stages for improved zonal isolation.

Product Overview

A stage collar is part of a stage cementing tool system used to divide the cementing operation into multiple stages. It is installed within the casing string before running down the well and provides selective fluid communication to the annulus through ports. A free drill-out stage collar uses a free-fall opening plug—instead of a mechanical or hydraulic shift—to uncover circulation ports. Once the closing plug reaches its seat and pressure is applied, the assembly falls to the bottom of the borehole under gravity, removing the need for an additional drill-out operation.

This tool is especially effective for vertical well cementing where gravity-driven mechanisms are reliable and efficient.

Key Features & Advantages

• Free Drill-Out Opening System
  The opening and closing process is performed by gravity-activated free fall of plug and seat assemblies, eliminating the need for conventional drill-out tools.

• Designed for Stage Cementing
  Provides port access for staged cementing in oil and gas wells, enabling more efficient zonal isolation and reduced cement contamination.

• Smooth Operation for Vertical Wells
  Specifically suitable for vertical well applications where gravity-based activation is effective.

• Clear Parameter Layout
  Available in sizes 5-1/2″ and 7″ with defined opening and closing pressures for predictable field performance.

Technical Specifications

Please send us your required specifications, parameters, or technical drawings. Our expert team will help confirm the suitable model and provide a factory quotation within 24 hours.

Email: info@shangshanpetro.com
Contact: Contact Us for a Quote

Applications

The Free Drill-Out Stage Collar is commonly used for:

• Stage cementing of casing strings in oil and gas wells

• Zonal isolation during cement displacement

• Applications where gravity-activated opening is preferred

• Vertical well completion operations

This tool helps optimize cement placement and zonal isolation by allowing cementing in multiple stages without the need for mechanical or hydraulic shifting tools.

Frequently Asked Questions

Q1: What is a free drill-out stage collar?
A free drill-out stage collar is a type of stage cementing tool that uses gravity-activated plug assemblies to open and close circulation ports, eliminating the need for an additional drill-out after cementing.

Q2: How does it work compared with regular stage collars?
In a free drill-out stage collar, once the closing plug lands on the seat and pressure is applied to shear the pins, the plug and seat assembly fall under gravity to the bottom of the hole, removing the need for a separate drill-out step.

Q3: What size options are available?
This product is available in 5-1/2″ and 7″ sizes, with defined opening and closing pressures suitable for standard cementing operations.

Q4: Is this tool suitable for deviated or highly angled wells?
The free gravity-activated mechanism works best in vertical wells due to reliance on gravity to drive the plug assembly downward.