Kelly Terminal Joint – Function, Types & Pricing in 2025
Focus Keyword: Kelly Terminal Joint
LSI Keywords: drilling rig kelly joint, oilfield kelly connection
Introduction: What is a Kelly Terminal Joint?
In oil and gas drilling operations, the Kelly terminal joint plays a critical role in transferring rotary motion from the rotary table to the drill string. It connects the kelly bar to the swivel or top drive, making it an essential part of the drill rig’s drive system.
This blog explores the function, types, and pricing of Kelly terminal joints to help you make an informed purchase decision.
What Does a Kelly Terminal Joint Do?
A Kelly terminal joint (also called a Kelly saver sub or Kelly connection) is designed to:
- Provide threaded or welded connection between the swivel and kelly bar
- Withstand high rotary torque and axial loads
- Protect the kelly bar threads from repeated wear and tear
- Enable quick disassembly during maintenance or rig-up
These joints are commonly manufactured from AISI 4145H or 4130 steel, heat-treated for superior toughness and durability.
Technical Specifications
| Specification | Details |
|---|---|
| Thread Types | NC50, NC38, 4½” IF, 6?” REG, API IF |
| Material Grade | 4145H Modified, 4130 Alloy Steel |
| Surface Treatment | Phosphate Coated / Nitrided |
| Tensile Strength | 110,000 – 140,000 psi |
| Connection Type | Box x Pin / Pin x Pin / Box x Box |
| Standard Compliance | API Spec 7-1, API Spec Q1 |
Kelly Terminal Joint Price in 2025
The price of a Kelly terminal joint can vary significantly depending on its size, material, and threading type.
Estimated Price Range:
- Domestic (India): ?28,000 – ?80,000 per unit
- International: $350 – $950 USD per unit
Price Depends On:
- Thread type and size (API REG/IF/NC)
- Hardfacing or phosphating requirement
- Load rating and tensile strength
- Supplier/manufacturer and quantity ordered
Common Applications
- Land-based oil & gas rigs
- Offshore drilling platforms
- HDD (Horizontal Directional Drilling) rigs
- Mining and geothermal rigs
Kelly terminal joints are used in both vertical and directional drilling where reliable torque transmission is critical.
How to Choose the Right Kelly Terminal Joint
Before making a purchase, consider the following:
- Match the thread type with the kelly and swivel
- Ensure API certification and material traceability
- Ask for Material Test Reports (MTRs) and inspection data
- Choose surface treatment (like hardbanding or nitriding) for longer life
- Compare at least two supplier quotes
Trusted Suppliers in India
Looking for high-quality Kelly terminal joints in India? Here are trusted names:
- Titan Steel & Engineers – Navi Mumbai, Maharashtra
- DrillTools India Pvt Ltd – Hyderabad
- WellTech Drilling Supplies – Ahmedabad
Explore our Drilling Tools & Accessories and Rotary Kelly Bars product pages.
Get a Quote for Kelly Terminal Joint
Need help choosing the right joint or want a quick quote?
Contact Us:
- Phone: +91 7385863226
- Email: sales@titansteel.in
- Address: Plot No. 15, Khan Compound, Taloja M.I.D.C.
Navi-Mumbai 410208, Maharashtra, INDIA
Conclusion
Understanding the Kelly terminal joint helps you extend the life of your drilling equipment and reduce downtime. With the right specifications and a trusted supplier, you can ensure safer and more efficient drilling operations.
