Problems and Solutions: Oil Swabbing

swab017.jpg.Swabbing is the act of pulling fluid from the well bore through the use of wire rope and cup assembly. Swabbing equipment includes a swabbing assembly, lubricator with an oil saver, and shut-off valve on the well, also called a swabbing valve.

General precautions during all swabbing operations:

  • Conduct swabbing operations during daylight hours.
  • Keep all personnel clear of the derrick or within six feet (two meters) of the wellhead during swabbing operations.
  • Locate swab tanks at least 100 feet (30 meters) from the well, where location allows.

Potential Hazard:

  • Loss of well control.

Possible Solutions:

  • Use appropriate equipment, rated for the expected pressures, to shut in the well.
  • Inspect lubricators, swages, and unions for defects such as cuts, corrosion, and thread damage before use.
  • Adjust oil savers by remote control with a hydraulic pump placed safely away from the wellhead.
  • Train all personnel in emergency evacuation procedures.

Potential Hazard:

  • Fire, explosive, or respiratory hazard from leakage or venting of oil or gas from tanks, lines or lubricator.

Possible Solutions:

  • Place fire extinguishers in accessible positions.
  • Move sources of potential ignition (such as, open fires for melting of babbitt) to designated areas at a safe distance from the wellhead or flammable liquid storage areas such as the swab tank before swabbing.
  • Make provisions to contain spilled flammable liquids.
  • Monitor the oil saver for wear and potential leakage.
  • Remove all spillage of flammable liquids from equipment, cellars, rig floor, and ground area adjacent to the wellhead.
  • Wear proper PPE, including respiratory protection, as required.

Potential Hazard:

  • Being struck by a pressurized line.
  • Being exposed to a high-pressure connection failure caused by mismatched or excessively worn hammer unions.

Possible Solutions:

  • Avoid approaching, walking over or standing near pressurized lines.
  • Securely anchor pressurized lines to prevent whipping or bouncing caused by pressure surges.
  • Use proper equipment inspection techniques to include hammer unions (Note: This is a particular problem with 602 and 1502 and others, as they will couple but will not hold beyond the lower pressure rating number).
    • High Pressure Lines and Hammer Unions. International Association of Drilling Contractors (IADC) Alert 98-01, (1998).
    • More On Mismatched Hammer Unions. International Association of Drilling Contractors (IADC) Alert 99-33, (1999).
    • Additional Serious Incidents With Mismatched Hammer Unions. International Association of Drilling Contractors (IADC) Alert 00-15, (2000).

Potential Hazard:

  • Being struck by pressurized fluids or the lubricator when removing the lubricator from the well.
  • Getting strains and sprains from handling the lubricator.

Possible Solutions:

  • Close the shut-off valve and bleed the pressure from the lubricator before removing it.
  • Use a lubricator that will allow removal of the swab or other tools with the well shut in (valve closed).
  • Use a dolly or other method to minimize manual handling of the equipment.

Potential Hazard:

  • Pinching fingers between swab assembly and lubricator when changing swab cups or mandrels.

Possible Solutions:

  • Use a winch line, where available, not the swab line, to handle the lubricator.
  • Use a lubricator that will allow removal of the swab or other tools with the well shut in (valve closed).

Additional Information:

  • Standards. American Petroleum Institute (API).
    • RP 54, Occupational Safety for Oil and Gas Well Drilling and Servicing Operations. (2007, March).

Reference: osha.gov