Product Overview

DEENPU SL Series Drilling Swivel with Integrated Kelly Spinner — API 8C Standard, 110–585 Ton Capacity

The Drilling Swivel is a critical component suspended directly below the traveling block and above the kelly on a drilling rig. It serves the essential dual function of allowing the kelly and drill string to rotate freely while the traveling block remains stationary, and simultaneously introducing high-pressure drilling fluid into the rotating drill string through the gooseneck and washpipe assembly.

Deenpu Machinery’s SL Series Drilling Swivels are designed and manufactured to API 8C standards, covering static load capacities from 110 tons to 585 tons with dynamic load ratings up to 410 tons. Each swivel features a high-strength alloy steel body and frame, advanced high-pressure drilling fluid sealing system, and a keyless connection between the optional Kelly spinner and the central pipe. All units operate at a maximum speed of 300 RPM with a standard working pressure of 35 MPa (5,000 PSI).

The swivel comprises precision-engineered components including the bail, gooseneck, upper shell, main body, lower shell, swivel stem, main shaft, and a multi-stage sealing system. Our integrated swivel and Kelly spinner combination provides drillers with a complete rotary and fluid circulation solution in one assembly, eliminating the need for separate equipment mounting and alignment.

Technical Drawing

DEENPU SL Series Swivel Technical Drawing — Component Layout and Interface Dimensions

The swivel assembly drawing above illustrates the key structural components and their arrangement. Main load-bearing elements including the bail, upper and lower shells, and main body are fabricated from high-strength alloy steel for maximum durability and service life. The central pipe features a keyless connection to the Kelly spinner, eliminating stress concentrations and simplifying assembly and maintenance. The gooseneck and washpipe assembly provide the high-pressure drilling fluid path with multi-stage dynamic sealing.

How the Swivel Works

The drilling swivel performs three critical functions simultaneously during drilling operations:

1. Rotational Decoupling — The swivel body is suspended from the traveling block via the bail and remains rotationally stationary. Inside, a precision bearing assembly allows the central stem and shaft to rotate freely with the drill string. This decoupling is what makes rotary drilling possible; without a swivel, the entire traveling block assembly would have to rotate.
2. High-Pressure Fluid Circulation — Drilling mud enters the swivel through the stationary gooseneck connection and passes through a rotating washpipe and seal assembly into the central stem. The high-pressure sealing system maintains fluid integrity at up to 35 MPa (5,000 PSI) while the stem rotates at up to 300 RPM, preventing leakage and ensuring consistent mud delivery to the bit.
3. Load Transmission — The entire weight of the drill string is transmitted through the swivel’s main bearing assembly to the bail and upward to the traveling block. Deenpu swivels are rated for static loads up to 585 tons with dynamic load ratings sufficient for continuous drilling and tripping operations.

When equipped with the optional Kelly spinner, the swivel provides powered rotation of the kelly during connections, eliminating manual spinning chain operations and improving rig floor safety. The keyless connection between spinner and central pipe ensures zero backlash and maximum torque transfer efficiency.

Key Features

Applications

• Land drilling rigs — Mechanical and SCR drilling rigs from 1,000 HP to 3,000 HP requiring reliable swivel performance
• Workover rigs — Compact SL110 and SL135 models suitable for workover and well servicing operations
• Deep drilling operations — SL450 and SL585 models for deep and ultra-deep wells with high hook loads
• Directional and horizontal drilling — High-speed 300 RPM rating supports oriented drilling and PDM operations
• HPHT drilling — 5,000 PSI sealing system suitable for high-pressure, high-temperature drilling programs
• Rig fleet upgrades — Drop-in replacement swivels for upgrading aging rig equipment to API 8C standards
• OEM equipment packages — Swivel supply for rig manufacturers and drilling equipment integrators

Technical Specifications

All SL models: 300 RPM maximum speed, 35 MPa (5,000 PSI) working pressure. Static load rating per API 8C. Dynamic load rating based on 1,000,000 revolution bearing life (L10). Contact us for dimensional drawings and complete bearing specifications.

When Ordering, Please Specify

1. Rig SpecificationsRig horsepower and maximum hook load. Derrick type and traveling block model for bail compatibility.
2. Load RequirementsMaximum static hook load and expected dynamic drilling load. Select appropriate SL model from 110 to 585 tons.
3. Working PressureMaximum anticipated mud circulating pressure. Standard configuration is 35 MPa (5,000 PSI).
4. Sub Connection TypeDrill stem connection size and thread type: 4-1/2″ REG-LH, 5-1/2″ REG-LH, 6-5/8″ REG-LH, or 6-5/8″ EG-LH.
5. Gooseneck ConnectionMud hose connection size and type: 3LP or 4LP standard. Alternative connection types available on request.
6. Kelly Spinner RequirementSpecify if Kelly spinner integration is required. Indicate the spinner model for compatibility matching.
7. Bail DimensionsBail size, type, and connection requirements. Compatibility with existing elevator links and traveling block.
8. Certification RequirementsAPI 8C certification, material test certificates (MTC), NDT reports, and third-party inspection (DNV, BV, SGS).
9. Spare Parts PackageRecommended spare parts: washpipe packing kit, main bearing set, seal kit, and gooseneck O-ring set.
10. Shipping & DeliveryDelivery destination and preferred shipping method. Export packaging (fumigated wooden crate) included as standard.

Custom Manufacturing & OEM Capability

• Load Capacity Customization — Custom static load ratings available beyond the standard 110–585 ton range for specialized drilling applications.
• Connection Adaptation — Non-standard sub connections, gooseneck sizes, and bail interfaces manufactured to customer specifications.
• Pressure Rating Upgrade — High-pressure variants with enhanced sealing systems for working pressures exceeding 35 MPa (5,000 PSI).
• Bearing Configuration — Alternative bearing arrangements for extended service life, higher dynamic loads, or specialized drilling conditions.
• Kelly Spinner Integration — Custom spinner mounting interfaces, drive adapter plates, and keyless coupling designs.
• Material Specifications — Alternative alloy steel grades, stainless steel trim options, and specialized coatings for corrosive environments (H2S, CO2).
• Branding & Documentation — Customer-specific nameplates, paint colors, manuals, and certification packages.

Quality Control & Testing Standards

• Main bearing assembly load tested to 1.25x rated static capacity with certified load cell verification.
• Complete swivel assembly function tested at factory: full-speed rotation test, pressure integrity verification, and dynamic sealing performance evaluation.
• Washpipe and sealing system hydrostatically tested to 1.5x rated working pressure (52.5 MPa / 7,500 PSI).
• Ultrasonic testing (UT) and magnetic particle inspection (MPI) on all load-bearing structural weldments and forgings.
• Material test certificates (MTC) per EN 10204 3.1 for all pressure-containing and load-bearing components.
• Dimensional inspection report with critical interface dimensions verified against engineering drawings.
• FAT (Factory Acceptance Test) performed before shipment — customer or third-party witness attendance optional.
• Third-party inspection and certification by DNV, BV, SGS, or ABS available upon request.
• Complete quality dossier provided with each unit: MTCs, NDT reports, pressure test certificates, and dimensional inspection reports.

Frequently Asked Questions