Heavy Weight Drill Pipe Advantages

What Is a Heavy Weight Drill Pipe?

A type of drillpipe whose walls are thicker and collars are longer than conventional drillpipe. HWDP tends to be stronger and has higher tensile strength than conventional drillpipe, so it is placed near the top of a long drillstring for additional support.

Heavy Weight Drill Pipe Advantages

Heavy weight drill pipe (HWDP) is commonly used in the vertical section of the hole, providing weight on the bit for directional drilling while maintaining more flexibility than a drill collar. In the industry, it is also known as hevi-wate or HWDP.

HWDP features a "center upset," or wear pad, that extends tube life by protecting the outer diameter from wear by keeping the tube away from the hole wall. This design also reduces hole drag and differential sticking problems. HWDP has thicker walls, longer upsets, and higher tensile strength compared to conventional drill pipe. It comes in various specifications.

HWDP is often used to transition between the drill collars and the drill pipe. This flexible transition helps reduce fatigue failures that typically occur just above the bottom hole assembly (BHA).

Difference Between Drill Pipe and Heavy Weight Drill Pipe

Drill Pipe

Drill pipe is the fundamental component of the drill string. Its main functions are to transmit torque and transport drilling fluid, enabling the wellbore to be continuously deepened as the drill pipe is gradually lengthened. Consequently, drill pipe plays a crucial role in oil drilling.

The drill pipe is made of seamless steel with a wall thickness typically between 9-11mm. It consists of two parts: the drill pipe body and the drill pipe joint. These components are butt welded together using friction welding.

Heavy Weight Drill Pipe

The weighted drill pipe, a component of the drill string, has a moderate weight per unit length. It features a heavy wall body with extended joints.

The outer diameter of the weighted drill pipe is similar to that of the standard drill pipe to facilitate drilling rig operations. A key characteristic of weighted drill pipe is its ability to bear pressure like a drill collar. It also features a unique wear band in the center, which acts as a stabilizer, improves rigidity within the drill string, and reduces well deviation.

The weighted drill pipe is similar to the oil drill pipe, being a hollow steel column approximately 10 meters in length. However, each piece is heavier than an oil drill pipe, with a wall thickness 2 to 3 times greater. The weighted drill pipe is connected between the drill pipe and the drill collar, and it can partially replace the drill collar. Its design allows for simpler suspension, convenient tripping operations, and reduced tripping time.

Difference Between Drill Pipe And Drill Collar:

The drill collar is thicker than the drill pipe, and the weight per unit length is heavier. The lower part of the drill collar is connected with the drill bit, and the upper part is connected with the drill pipe. The functions are similar. The drill pipe mainly transmits motion and power. The drill collar is stronger than the drill pipe and directly drives the drill bit to work.