Drilling stuck pipe

The drilling string got stuck after remaining motionless in the hole circulation can be broken and continued at normal pressure. Permeable formation is exposed above the bit. The borehole is clean and in good condition, see Diagnosis of stuck pipe as above as above... 

We will discuss four main topics stuck pipe prevention, drillstring failure prevention, ROP optimization and real-time use of drilling mechanics. 

A more pervasive problem is the maintenance of wellbore stability in shale formations [i.e., formations that have a high clay content, typically in excess of 50 wt% (10)]. In the presence of water, shales can take up water and swell and disperse or they can fracture. Problems associated with wellbore stability in shale sections are sticking of the drill pipe (usually termed stuck pipe), hole enlargement, and excessive generation of drilled solids. 

The overall purpose of the suggested approach is to establish an adequate procedure for determining which of the available products that will perform best in real offshore situations, i.e. which drilling jar that will use least time for freeing stuck-pipe. The main quantity of interest is the stuck-pipe downtime. 

Drill cuttings that settle can cause bridges and fill, whieh ean cause stuck-pipe and lost circulation. 

This term describes a situation whereby the drill string cannot be moved up or down or rotated anymore. The pipe can become stuck as a result of mechanical problems during... 

Some clay minerals may absorb some of the water contained in the drilling mud. This will cause the clays to swe//and eventually reduce the borehole size to the point where the drill pipe becomes stuck. Prevention mud additives which prevent clay swelling e.g. potassium salt. 

If the drill string becomes differentially stuck, mechanical methods or spotting fluids can be appHed, or the hydrostatic pressure can be reduced (147). In general, penetration of water- or oil-based spotting fluids into the interface between the filter cake and the pipe accompanied by dehydration and cracking results in reduction of differential pressure across the drill string (147,148). Spotting fluids are usually positioned in the open hole to completely cover the problem area. 

Calculate the maximum value of a rotary torque that may be applied to the drill pipe as specified in Example 5 if the actual working tension load P = 300,000 lb. (For instance, pulling and trying to rotate a differentially stuck drill string.)... 

Jars provide an upward or downward shock (or Jar) to the entire drill string. Early attempts to recover stuck drill pipe motivated the development of Jars. 

Key seats occur in dog legs of the borehole. The drill pipes cut a groove in the wall at their dimension and when tool joints or drill collars are pulled up, the drillstring gets stuck. 

Moore, E. E., Fishing and freeing stuck drill pipe, The Petroleum Engineer, April 1956. 

Differential pressure sticking occurs when the drill pipe becomes imbedded in the mud wall cake opposite a permeable zone. The difference between the hydrostatic pressure in the drill pipe and the formation pressure holds the pipe in place, resulting in a sticking pipe. Differential sticking may be prevented, and a stuck drill bit may be freed, using an oil-mud or an oil- or water-based surfactant composition. 

Various additives have been proposed to assist in freeing a stuck drill pipe, the most common of which is diesel oil that is added directly to the drilling mud as a spotting fluid. However, this is not always successful. An additive comprising an oil-in-water microemulsion has been proposed. Sodium dodecyl... 

This is like a big shotgun or the old-fashioned blunderbus. It is simply a pipe with a cap on one end drilled for a fuse. It is stuck in a tree or laid down. If you hold it you ll be kicked a mile. 

Uses Surface-act. component for formulating weighted spotting fluids which provide surfactant and lubricant props, to free stuck drill pipe Properties Cloudy vise, liq. disp. in water disp. in oil sp.gr. 0.98 vise. 3000 cps ... 

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