During a drilling operation, the casing wall gets clogged with mud, cement, rust, scale buildup, and other obstructions which can hamper the operation of downhole tools. The casing scraper removes these deposits including burrs and irregularities in the casing ID.
For the life of a wellbore, debris is a recurring issue and ranges from drilling fluid residue to perforation fragments. Operating downhole tools in a casing that is not cleaned can damage completion equipment, cause production losses, and damage the formation.
Casing scrapers can:
- Remove paraffin, mud, and hardened cement
- Remove burrs and nicks caused by fishing tools and drill bits
- Take care of dents caused by tool mishandling
- Remove burrs from perforations
- Remove bullets embedded in the casing
In general, casing scrapers consist of a single scraper body, a blade retainer, scraper blades with springs and retainer rings. The body of the scraper is splined and locks the blades into the body to ensure safety. The blades are made of high-quality steel for durability and proper scraping. The blades can cover 360° surface area and are designed with a long taper to pass easily through casing connections.
The springs in the blade keep the blade firmly pressed against the pipe and allow it to compress and depress during scraping operations. A blade retainer and retainer rings hold the blades and springs in place on the body of the scraper. The scraper is run into the casing or tubing by rotation or spudding.
