Torque Stop Sub

Torque Stop Sub

A Torque Stop Sub is a specialized downhole drilling tool installed within the drill string or Bottom Hole Assembly (BHA) to control and limit the transmission of excessive torque between connected drilling components. It protects critical tools such as mud motors, Measurement While Drilling (MWD) tools, Logging While Drilling (LWD) systems, rotary steerable systems (RSS), and fishing assemblies from damage caused by excessive torsional loads.

Torque Stop Subs are engineered to improve drilling efficiency, reduce equipment wear, and enhance the operational life of expensive downhole tools, particularly in directional, horizontal, and extended-reach drilling operations.

Applications

Oil and gas drilling

Directional drilling

Horizontal drilling

Extended Reach Drilling (ERD)

Offshore drilling

Onshore drilling

Deepwater drilling

Rotary Steerable System (RSS) operations

MWD and LWD drilling

Fishing operations

Workover operations

HPHT wells

Technical Specifications

Specification Details

Product Type Torque Stop Sub

Material High-Strength Alloy Steel (AISI 4145H Modified or Equivalent)

Manufacturing Standard API Spec 7-1

Quality Standard API Q1, ISO 9001

Outside Diameter (OD) 3⅛" – 11"

Inside Diameter (ID) Application Specific

Length 3 – 10 ft (0.9 – 3.0 m)

Connection Type API REG Pin & Box, IF, NC, FH Threads

Torque Capacity Up to 80,000 ft-lbf (depending on size and model)

Tensile Strength Up to 2,000,000 lbf

Operating Pressure Up to 20,000 psi

Operating Temperature Up to 204°C (400°F)

Service Standard and Sour Service (H₂S/CO₂)

Corrosion Protection Phosphate Coating or Equivalent

Key Features

Limits excessive torque transmission

Protects sensitive downhole tools

High torsional strength

Excellent fatigue resistance

Heavy-duty alloy steel construction

Precision-machined API threaded connections

Corrosion-resistant finish

Suitable for HPHT environments

Compatible with most Bottom Hole Assemblies (BHAs)

Long operational service life

Working Principle

The Torque Stop Sub is positioned within the drill string or Bottom Hole Assembly.

During drilling:

Rotational torque is transmitted through the drill string.

The Torque Stop Sub monitors and limits excessive torsional loads.

When torque approaches the preset operating limit, the tool absorbs or restricts excess torque to prevent damage to connected equipment.

Normal torque transmission resumes once operating conditions return to acceptable levels.

This protects expensive downhole components while maintaining drilling performance.

Advantages

Protects MWD, LWD, RSS, and mud motors from excessive torque

Reduces equipment failure and repair costs

Improves drilling reliability

Extends the service life of downhole tools

Minimises non-productive time (NPT)

Suitable for high-torque drilling environments

High mechanical strength and durability

Easy integration into existing BHAs

Low maintenance requirements

Improves operational safety

Available Types

Standard Torque Stop Sub

Heavy-Duty Torque Stop Sub

Adjustable Torque Stop Sub

Fixed Torque Stop Sub

Directional Drilling Torque Stop Sub

Mud Motor Torque Stop Sub

MWD Protection Torque Stop Sub

LWD Protection Torque Stop Sub

HPHT Torque Stop Sub

Custom Torque Stop Sub

Compatible Equipment

Drill Pipe

Heavy Weight Drill Pipe (HWDP)

Drill Collars

Non-Magnetic Drill Collars

Mud Motors

Rotary Steerable Systems (RSS)

MWD Tools

LWD Tools

Hydraulic Drilling Jars

Stabilizers

Fishing Tools

Bottom Hole Assemblies (BHA)

Inspection Before Deployment

Inspect the tool body for cracks, corrosion, or impact damage.

Verify API threaded connections and dimensions.

Check torque-limiting mechanism for proper operation.

Inspect sealing surfaces and internal components.

Confirm pressure and torque ratings meet the drilling programme.

Perform non-destructive testing (NDT) where required.

Ensure thread protectors are fitted during transportation.

Maintenance

Clean thoroughly after each drilling operation.

Inspect wear surfaces and torque-limiting components.

Replace damaged seals, bearings, or internal parts as required.

Lubricate moving components using approved lubricants.

Protect threaded connections with thread protectors during storage.

Store in a clean, dry environment.

Maintain inspection, servicing, and calibration records.

Industries Served

Oil & Gas Exploration

Offshore Drilling Contractors

Onshore Drilling Companies

Well Intervention Services

Geothermal Energy

Mining Exploration

Energy Service Companies

Torque Stop Sub Available for Sale & Lease

We supply premium-quality Torque Stop Subs for sale and rental, providing dependable torque management and protection for critical downhole drilling equipment. Our tools are manufactured to API and ISO standards and are engineered to perform reliably in demanding drilling environments, including offshore, onshore, deepwater, and HPHT applications.

Our Services

Torque Stop Subs for Sale

Short-Term Equipment Rental

Long-Term Lease

Bulk Supply

Worldwide Delivery

Fast Equipment Mobilisation

Equipment Inspection & Certification

Technical Consultation

Installation Support

Preventive Maintenance

After-Sales Service

Why Choose Our Torque Stop Subs?

Manufactured to API Spec 7-1 and international quality standards

Designed to protect valuable downhole tools from excessive torsional loads

Suitable for vertical, directional, horizontal, offshore, and deepwater drilling operations

Available in multiple sizes, torque capacities, and connection types

High resistance to wear, fatigue, and corrosion

Competitive pricing for both purchase and lease

Fast delivery and expert technical support

Our Torque Stop Subs are engineered to improve drilling efficiency, protect high-value downhole equipment, and reduce non-productive time. Whether you require a single unit or a complete Bottom Hole Assembly (BHA) solution, we provide reliable equipment backed by experienced technical support and responsive customer service.