High-Precision Drill Stem Subs from China Suppliers - API Spec 7-1 Certified Factory Products
Product Application
Drill stem subs serve as critical components in drilling operations, acting as connectors between drill pipes and drill collars. Each sub features a drill pipe connection on one end and a drill collar connection on the other, enabling seamless integration of drilling equipment.
Crossover subs, a specialized type of sub, are designed to adapt to different connector types or sizes and connections.
The sub that connects the drill bit to the last drill collar is the bit sub.
Types of Sub
There is a wide range of subs available to meet the specific needs of modern drilling operations:
Straight Crossover Sub (Box/Pin, Box/Box, Pin/Pin)
Crossover Sub with Float Bore (Box/Pin, Box/Box, Pin/Box)
Bit Sub (Box/Box)
Top Drive Saver Sub (Pin/Pin)
Kelly Saver Sub without rubber protector (Box/Pin)
Kelly Saver Sub with a stretched on rubber protector (Box/Pin)
Lift Sub (18 deg taper or squa
Lift Plug (None/Pin)
Product Features
Premium Materials
We utilize only the highest quality, fully traceable 4145-H heat-treated alloy steel bars, ensuring superior mechanical properties in strict accordance with API and NS-1 standards. For applications demanding enhanced wear resistance and torsional strength.
Precision Threading
Threads are cold rolled to ensure a perfect fit and maximum strength. Standard phosphating of threads and seals provides exceptional anti-corrosion and anti-galling protection, minimizing the risk of galling during initial makeup.
Customized Solutions
We offer customized drawings and detailed product data tables upon request, enabling our clients to make informed decisions and select the perfect subs for their specific needs.
Frequently Asked Questions
What is the main function of a drill stem sub?
Drill stem subs act as critical connectors between drill pipes and drill collars, enabling the seamless integration of drilling equipment during operations.
What is a crossover sub used for?
Crossover subs are specialized components designed to adapt to different connector types, sizes, and connections within the drill string.
Which sub connects the drill bit to the drill collar?
The bit sub is specifically used to connect the drill bit to the last drill collar in the string.
What materials are used to manufacture these subs?
Our subs are manufactured using only the highest quality, fully traceable 4145-H heat-treated alloy steel bars, complying strictly with API and NS-1 standards.
How are the threads protected against galling and corrosion?
The threads are cold rolled for maximum strength and undergo standard phosphating on threads and seals to provide exceptional anti-corrosion and anti-galling protection.
Can I get customized subs for specific drilling requirements?
Yes, we offer customized solutions and can provide specific drawings and detailed product data tables upon request to meet your exact needs.