Description
Product Description
The mechanical stage collar, also known as a plug-operated stage collar, two-stage cementing tool, or mechanical cementing collar, is used to perform staged cement placement in casing cementing operations.
In challenging formations, conventional single-stage cementing may generate excessive hydrostatic and pumping pressure. This can break down weak zones, cause severe lost circulation, reduce cement placement quality, and increase the risk of remedial cementing. A properly designed mechanical stage collar allows operators to divide the cementing job into two stages, helping mitigate lost circulation and protect fragile formations during cement placement.
For field crews, the most serious risks are not only lost circulation, but also failure to open, failure to close, and accidental pressure-induced pre-opening. If the stage collar cannot open when the second-stage cement job starts, the cementing program may fail. If it cannot close and seal properly after cementing, well integrity may be compromised.
Our plug-operated mechanical stage collar is activated by an opening plug rather than circulating pressure. This design helps prevent pressure-induced pre-opening during circulation and improves control during field operation. The tool also features a compact body assembly, fewer moving parts, clear surface opening/closing indication, and an anti-rotation PDC drillable design to support reliable operation and efficient drill-out after cementing.
It is suitable for vertical wells and low-deviation wells, with recommended deviation up to approximately 30° from vertical.
What Problem Does It Solve?
| Field Risk | How the Mechanical Stage Collar Responds |
|---|---|
| Lost circulation across weak formations | Mitigates pressure load by dividing cementing into two stages |
| Formation breakdown during cementing | Reduces full-column pumping pressure on fragile zones |
| Failure to open during second-stage cementing | Plug-operated activation supports controlled opening |
| Pressure-induced pre-opening during circulation | Opening plug design prevents accidental pressure-triggered opening |
| Failure to close after cement placement | Closing function and surface indication support operation confirmation |
| Long drill-out time after cementing | Anti-rotation PDC drillable design improves drill-out efficiency |
| Complex field operation uncertainty | Clear surface opening and closing indications improve crew confidence |
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Name | Mechanical Stage Collar |
| Alternative Names | Plug-Operated Stage Collar / Two-Stage Cementing Tool / Mechanical Cementing Collar |
| Product Type | Stage Collar Body Assembly |
| Main Function | Two-Stage Cementing / Staged Cement Placement |
| Operation Method | Plug-Operated Mechanical Activation |
| Opening Control | Activated by Opening Plug |
| Pre-Opening Prevention | Prevents Pressure-Induced Pre-Opening During Circulation |
| Closing Control | Closing Plug / Mechanical Closing Function Available |
| Surface Indication | Clear Opening and Closing Indication |
| Drill-Out Design | Anti-Rotation PDC Drillable Stage Collar Design |
| Structure | Compact Body Assembly with Fewer Moving Parts |
| Applicable Wells | Vertical Wells / Low-Deviation Wells |
| Recommended Deviation | Up to 30° from Vertical |
| Application | Casing Cementing / Weak Formation Cementing / Lost Circulation Mitigation |
| Material | High Strength Alloy Steel Optional |
| Customization | Available According to Casing Size, Thread Type or Drawing |
Specification CTA
Need a custom specification?
Send us your tool model, working condition, material requirement, quantity or technical drawing. Our team can help confirm the suitable product configuration and provide a quotation.
Email: info@shangshanpetro.com
Contact: Contact Us for a Quote
Product Features & Benefits
Mitigates Lost Circulation in Weak Formations
The stage collar allows cement to be placed in two stages, reducing the pressure load applied to weak or fractured formations. This helps mitigate lost circulation and improves cementing success in pressure-sensitive zones.
Prevents Pressure-Induced Pre-Opening
Unlike pressure-activated tools, this plug-operated stage collar opens only after the opening plug is landed. This prevents accidental pre-opening caused by circulating pressure before the planned cementing stage.
Reliable Open and Close Operation
The mechanical opening and closing sequence provides controlled tool operation during two-stage cementing. Clear surface indications help confirm whether the tool has opened or closed as expected.
Compact Design with Fewer Moving Parts
The compact body assembly reduces internal complexity and minimizes failure points, improving downhole reliability during cementing operations.
Anti-Rotation PDC Drillable Design
The locking and anti-rotation structure supports faster drill-out after cementing. The anti-rotation PDC drillable stage collar design helps prevent spinning during drill-out and saves rig time.
Clear Surface Indication
Opening and closing indications at surface allow field crews to verify tool status, reducing uncertainty during critical cementing operations.
Suitable for Vertical and Low-Deviation Wells
This tool is designed for vertical wells and lowly deviated wells up to approximately 30° from vertical, making it suitable for conventional two-stage cementing programs.
Applications
The mechanical stage collar is widely used in:
Oil and gas well cementing
Two-stage cementing operations
Plug-operated stage cementing systems
Weak formation cementing
Lost circulation mitigation
Casing cementing programs
Vertical wells
Low-deviation wells
Stage cementing tool systems
Anti-rotation PDC drillable cementing assemblies
Quality Control
| Inspection Item | Description |
|---|---|
| Material Verification | Confirms material grade, heat number and traceability when required |
| Dimensional Inspection | Ensures accurate fit of body assembly and internal components |
| Thread Inspection | Checks casing thread accuracy according to project requirements |
| Opening Mechanism Check | Verifies plug-operated opening function |
| Closing Function Check | Confirms closing sleeve movement and sealing performance when required |
| Surface Indication Check | Checks opening and closing indication response |
| Anti-Rotation Function Check | Confirms anti-rotation structure for drill-out support |
| Drill-Out Design Review | Verifies PDC drillable and anti-rotation design requirements |
| Final Inspection | Ensures the mechanical stage collar is ready for field operation |
FAQ
What is a plug-operated mechanical stage collar?
A plug-operated mechanical stage collar is a two-stage cementing tool that is opened by an opening plug instead of circulating pressure. This helps control the timing of second-stage cementing and prevents pressure-induced pre-opening.
How does the stage collar mitigate lost circulation?
It divides the cementing job into two stages, reducing the pressure applied to weak formations. This helps mitigate lost circulation and reduces the risk of formation breakdown during cement placement.
What happens if a stage collar fails to open?
Failure to open can prevent the second-stage cementing job from being completed. This is why a reliable plug-operated opening mechanism and surface indication are critical.
How does the tool prevent accidental pre-opening?
The tool is not opened by circulating pressure. It is activated by the opening plug, which prevents pressure-induced pre-opening during circulation before the planned operation.
How is the stage collar closed after cementing?
The stage collar is closed by the designed closing sequence, typically using the closing plug or mechanical closing function depending on configuration. Surface indication helps confirm closing status.
What is the advantage of anti-rotation PDC drillable design?
The anti-rotation design prevents spinning during drill-out, while the PDC drillable structure helps reduce drill-out time after cementing.
What wells is this mechanical stage collar suitable for?
It is suitable for vertical wells and low-deviation wells, with recommended deviation up to approximately 30° from vertical.
Can the stage collar be customized?
Yes. It can be customized according to casing size, thread type, material requirement, cementing program and technical drawings.
Call to Action
If you need a reliable mechanical stage collar, plug-operated stage collar, or two-stage cementing tool for weak formation cementing and lost circulation mitigation, please send us your casing size, thread type, well condition, quantity or technical drawings.
Our team can provide customized stage cementing tool solutions for vertical wells, low-deviation wells and oilfield cementing projects.
Email: info@shangshanpetro.com
Contact: Contact Us for a Quote
