Casing is a steel pipe that is usually larger in diameter and longer than drill pipe and is used to line the hole to:
prevent the wall of the hole from caving in
prevent movement of fluids from one formation to another
aid in well control
Casing operations occur periodically throughout the drilling process starting with the surface casing, intermediate casing, and ending with production string which takes place during well completion.
The activities involved in casing operations can vary according to the type of casing being installed, but generally fall into these steps:
installing casing tools
running casing into the hole
installing casing accessories
circulating and cementing
Installing Casing Running Tools
In this process, specialized casing handling tools, such as the casing elevator and spiders, are installed to run casing.
Note: The special service supervisor should always hold a pre-job meeting with the special service crew and other involved personnel to review responsibilities and to coordinate the operations to be
being struck by or caught between tubulars and other objects during movement (such as being struck by tubulars being tailed into the rig floor)
experiencing strains and sprains from maneuvering tools
falling from work platform and/or stabbing board
Stand clear of suspended, hoisted or moving loads.
Be aware of tubulars or equipment being lifted through the V-door.
Use proper hand and foot placement to avoid pinch points, including use of tag lines.
Use rig floor winch or other powered equipment to handle heavy casing tools.
Use fall protection while installing equipment in the derrick.
Keep the area free from slip, trip, and falls.
Running Casing into the Hole
In these procedures, casing pipe is run into the hole to a pre-determined depth.
hazards are similar to those for drilling ahead or tripping
getting caught between, struck by, or pinched by the power tongs, casing or other equipment
being struck by or caught between tubulars and other objects during movement (for example, struck by tubulars being tailed into the rig floor)
falling from the stabbing board or work platform
getting struck by dropped objects
Include the casing crew and the drilling crew when conducting a JSA and pre-job safety meeting to coordinate the activities of casing operations.
Stand clear of suspended, hoisted, or moving loads. Be aware of tubulars or equipment being lifted through the V-door.
Emphasize all normal worker safety procedures, such as fall protection, PPE, placement of hands and feet, and teamwork and communication between workers.
Implement full fall protection program for the casing stabber.
Identify clearance between the stabbing board and casing elevators.
Secure all items used by the casing stabber overhead with a safety line.
Installing Casing Accessories
As casing is being run, accessories such as centralizers, scratchers, guide shoe, and a float collar are installed and used as needed.
Note: The special service supervisor should hold a pre-job meeting with the special service crew and other involved personnel to review responsibilities and to coordinate the operations
to be performed.
dropping guide shoe or float collar onto legs or foot
getting fingers pinched between tools and casing tongs when manually moving guide shoe or float collar
exposure to hazardous materials, especially thread lock compounds
Use winch, air hoist, or other powered equipment to handle guide shoe, float collar, or other heavy casing equipment.
Use appropriate PPE as required by the MSDS.
Keep fingers away from pinch points when moving accessories.
Circulating and Cementing
After the casing is landed, drilling fluid is circulated through the casing and annulus to remove any residual gases and to condition the mud.
After circulating and conditioning the mud, the casing is cemented. Cement is a powder consisting of alumina, silica, lime, and other substances that hardens when mixed with water. It is extensively used in
the oil industry to bond casing to the walls of the wellbore.
During this process the casing is reciprocated or rotated to allow the scratchers to work to remove excess wall cake to give the cement a better bond.
Usually another special servicing company is hired to conduct cementing operations.
being struck by high-pressure lines failing if not secured properly
having a high-pressure connection failure caused by mismatched or excessively worn hammer unions
Hobble high-pressure lines properly.
Use proper equipment inspection techniques to include hammer unions (Note: This is a particular problem with 602 and 1502, as they will couple but will not hold beyond the lower pressure rating number).
Ensure compatible high-pressure line connections.
Stay updated on safety alerts.
Video- Evolution of the Oil Industry
Before beginning this quiz, we highly recommend you review the module material. This quiz is designed to allow you to self-check your comprehension of the
module content, but only focuses on key concepts and ideas.
Read each question carefully. Select the best answer, even if more than one answer seems possible. When done, click on the "Get Quiz Answers" button. If you
do not answer all the questions, you will receive an error message.