What is a free point indicator?

The Free Point Indicator is an electromechanical assembly designed to accurately measure torque or stretch in harsh conditions. The basic Free Point tool assembly consists of bow spring or magnet, upper and lower anchors, and a sensor section to determine stuck point.

How does a free point tool work?

The free-point indicator operates by detecting stretch in the tubular when tension is applied at surface. If stretch is not detected, the string must be stuck above the tool; if stretch is detected, the string is free above the free-point indicator tool.

How do you find the depth of a stuck pipe?

1 ) Determine the free point constant (FPC) by this following formula:

  1. FPC = As x 2500.
  2. As = (OD2-ID2) x 0.7854.
  3. Depth of stuck pipe = (Pipe stretch in inch x free point constant (FPC)) รท Pull force in thousands of pounds.
  4. a) Determine free point constant (FPC):
  5. b) Determine the depth of stuck pipe:

What is differential sticking in drilling?

Differential sticking occurs in an open hole when any part of the pipe becomes embedded in the mud cake. When this happens, sticking can result because the pressure exerted by the mud column is greater than the pressure of the formation fluids on the embedded section.

How do you calculate pipe stretch?

Total Elongation is simply calculated by adding the components of elongation. Thus the total elongation is given by: S TOTAL = S tubing weight + S chemical weight + S pump force + S thermal S TOTAL = 16.2 ft + 2.2 ft + 0.2 ft + 16.8 ft .

What is differential stuck up?

How do you free a stuck differential?

Rotation or downward movement of the pipe offers a better chance of breaking the mud seal than does pulling it upward. In some cases, a differentially stuck string may be freed by reducing the mud weight, which in turn will reduce the differential pressure between the mud column and the permeable zone.

How can you recognize differential stuck?

Indicators of differential stuck pipe

  1. An increase in torque and drag.
  2. An inability to reciprocate the drillstring and, in some cases, to rotate it.
  3. Uninterrupted drilling-fluid circulation.

What is pipe stretch?

Pipe Stretch is the increase in length resulting from the combination of forces within the piping system.

What causes differential sticking?

Differential sticking typically occurs when high-contact forces caused by low reservoir pressures, high wellbore pressures, or both, are exerted over a sufficiently large area of the drillstring.

What causes stuck pipe?

Differential Sticking is one of the most common causes of pipe stuck. It can happen when there is differential pressure (overbalance pressure) pushing a drill string & BHA into permeable formations. Permeable formations for example are sand stone, lime, carbonate, etc.