Overshot Lifting Dogs / Latch Retracting Dogs

Wireline Overshot Lifting Dog | High-Strength Latch Retracting Dog

Maximize your trip efficiency and eliminate dropped inner tubes with our premium wireline overshot lifting dogs. Positioned at the core of the overshot assembly, these heavy-duty lifting dogs are engineered to provide an instantaneous, rock-solid grip on the inner tube spearhead, ensuring safe and smooth core retrieval from any depth.

Forged from ultra-high-strength alloy steel and treated with proprietary precision hardening, our lifting dogs resist the extreme tensile stresses and abrasive drilling fluids that cause lesser components to fail. When reliability downhole is non-negotiable, our lifting dogs keep your drilling operations moving forward without costly delays.


Chat on WhatsApp Request a Quote

Product Info

Overview

The lifting dog (or latch retracting dog) is the critical jaw mechanism inside the overshot that bears the entire weight of the core-filled inner tube during tripping. A worn or sub-par lifting dog risks dropping the inner tube downhole, leading to disastrous fishing jobs. Our lifting dogs undergo 100% non-destructive testing (NDT) to ensure zero internal defects, providing drilling contractors with ultimate peace of mind.

Technical Specifications

Feature / Parameter	Specification Details
Material	Premium Forged Chrome-Moly Alloy Steel (e.g., 4140/8620)
Manufacturing Process	Precision Forged & CNC Machined
Heat Treatment	Case-hardened / Core-refined for maximum toughness and surface wear resistance
Hardness	Surface Hardness HRC 58 - 62; Core Hardness HRC 35 - 40
Size Availability	Fully compatible with BQ, NQ, HQ, PQ, and oversized/thin-wall systems
Application	Wireline Overshot Assembly / Spearhead Point Retrieval

Key Features & Advantages

Advanced Metallurgy & Forging: Unlike cast alternatives, our forged lifting dogs possess an optimized grain flow, giving them unparalleled resistance to impact and metal fatigue.
Wear-Resistant Gripping Surface: The contact jaw area is induction-hardened to minimize wear from repetitive engagement with hardened spearheads, drastically extending part life.
Perfect Spring Synchronization: Designed to work flawlessly with overshot springs, ensuring rapid expansion and crisp retraction when releasing the inner tube at the surface.
Global Compatibility: 100% interchangeable with major international diamond drilling brands, allowing you to upgrade your existing overshot systems seamlessly.

Ordering Information

To ensure a perfect fit for your overshot fleet, please provide:

System Size: (e.g., B, N, H, P or NQ, HQ, PQ)
Overshot Type: Standard wireline, quick-release, or underground (pump-in) overshot.
Mating Components: We highly recommend replacing lifting dogs in pairs along with the Lifting Dog Spring for optimal performance. Contact us for combined kit pricing.