*covering Seat To help Rotation Lost Problems
*Minimize downhole pressures
*Drill String Movement
*Minimize Rotation Loss Problem Severity By dwindling ROP
*slush Pumps Effect On Rotation Loss
*Drill String trouncing
*covering & Drill String Design
*Wellbore Kicks
*Control Mud parcels

As this composition is one of five papers to cover the lost of rotation problem, I recommend visiting this links for better understanding

*Important preface For Lost Rotation Problem
*Causes Of Lost Rotation Problem
*Remedial Of Lost rotation Problem,
*Lost Of Rotation Material Used In drilling

  

preventative styles & Mitigation Of circu Lost Problems

Good planning and proper drilling practices are the keys to precluding misplaced rotation by minimizing inordinate pressures on the conformation. Several measures can be taken to help or minimize lost circu

1 casing Seat To help Rotation Lost Problems

Set the covering in the applicable zone so the fracture grade of the conformation at the covering shoe will be sufficient to support the hydrostatic head of heavier guck needed to balance pressures in the conformations below.

2 Minimize downhole pressures.

Pipe movement shouldn't exceed critical pets when tripping pipe. When the drill string is run in the hole, there's a surging pressure from the piston effect of the bit and collars adding the pressure wielded on the bottom of the hole. Good drilling practices will keep these pressure surges within the fracture and conformation pressure.
numerous wells witness lost rotation while running pipe or covering into the hole. The length of pipe in the hole affects the magnitude of the swell. Tests show that the inflow of slush along the pipe creates utmost of the pressure swell. The longer the pipe, the lesser the swell. thus, the deeper the well, the slower the pipe should be run into the hole as the depth of the bit increases.
lower annular concurrences also increase swell pressures much in the same way annular pressure losses are increased as annular concurrences drop.

3 Drill String Movement

Rapid movement of pipe while circulating also causes indeed lesser pressure surges. Rapid “ spudding ” of the pipe or fast reaming while circulating can produce large surges. Wash and ream cautiously through islands.

4 Minimize Rotation Loss Problem Severity By dwindling ROP

veritably high ROP loads the annulus with slices, therefore increases the Drilling ECD, making any farther surging on connections more likely to beget fracturing. It's important to control the ROP and circulate previous to making connections when the ECD is near the fracture pressure.
Maintain the slices attention in the annulus below 4 to minimize the effect of slices on ECD.

5 Mud Pumps Effect On Rotation Loss

Rapid starting or stopping of the slush pumps can beget pressure surges. Starting the pumps too fleetly will produce a pressure that can beget misplaced rotation, especially when breaking rotation on bottom after a trip. Part of the swell is caused by pressure needed to break the gel structure of the slush.

Rotating the pipe when starting rotation will prop breaking the gel strengths and greatly reduce the swell pressure. The other part of the swell is the pressure needed to accelerate the slush column to the normal circulating rate. Maintaining low gel structure and gradationally adding the pump rate will reduce this type of swell pressure. Breaking rotation at several intervals when tripping in hole is another way to minimize these pressures.

6 Drill String trouncing

Use enough drill collars to keep the neutral point in the Bottom Hole Assembly( BHA) to minimize drill string trouncing.

7 Casing & Drill String Design

During the drilling mastermind ‘s planning phase of the well, coverings design and drill string design should be finagled for proper and safe operation, and also to optimize hydraulics for good hole cleaning and minimal ECD, especially in sensitive areas.

8 Wellbore Kicks

Avoid kicks if possible. Shut- in pressure at the face is transmitted down the wellbore, frequently breaking the conformation down at the weakest point. This not only results in loss of rotation, but losing control of the well.
Proper exploration, well planning and prosecution will minimize the possibility and inflexibility of a kick. Those responsible for the operation at the wellsite should always be apprehensive of the maximum shut- in containing pressure and volume. The volume of the intruding fluid is directly related to the shut- in pressures and should beminimized.However, proper kill procedures should be used to maintain the right constant bottom- hole pressure needed to kill the well, If a well has to be shut- in.

9 Control Mud Properties

Viscosity and Gel Strengths
High density and Gel Strengths increase swell pressures each time rotation is intruded and restored. They also increase the ECD while drilling. These values should be optimized to insure good hole cleaning and solids suspense, and minimize ECD, swell and tar pressures. numerous times slush parcels can't be kept at a position which will give acceptable hole drawing due to other functional considerations.

Advanced inflow rates and aggressive drill pipe gyration are the stylish styles to ameliorate hole cleaning. High density reaches are recommended in similar cases where good hole cleaning is questionable. These reaches are generally made of slush from the active system that has been viscosified by additions of bentonite, polymers or Lost- Rotation Material( LCM).

The use of LCM in these reaches is preferable in numerous cases since they're screened out at the face and have no endless effect on the density of the slush. Controlling the ROP may be necessary if effective hole cleaning can't be achieved. Although this may outstretch the rotating hours, it'll generally be less precious than the costs incurred by losing returns.

Drill Solids & Fluid Loss

Control drill solids at the minimal practical position and add proper treatment to minimize sludge- cutlet figure- up. Anything that reduces the annular concurrence causes a pressure increase. Balling of the bit, collars, stabilizers or tool joints decreases the annular concurrence.

In the case of expansive bit and/ or stabilizer balling, a significant pressure will be wielded on the conformation. An increase in drag or swabbing on connections are possible pointers of agglomerating. occasionally a ball can be pumped off a bit, but if that fails, the common practice of spudding the bit should be avoided. The combination of the reduced annular concurrence and the pipe swell can beget the pressure to exceed the fracture pressure.

High fluid- loss guck deposit a thick sludge cutlet that can reduce the annular concurrence. The lower annular space increases the ECD. thus, fluid loss and sludge- cutlet consistence should always be controlled in the proper range. slush that develops a thin, strong sludge cutlet is more effective in precluding lost rotation to small fractures or pores.

MUD viscosity

Drill with minimal slush viscosity. This not only enhances the ROP but also diminishes other slush- related goods.

Selection Of Bridging Material

A good selection of the proper size of bridging accoutrements helps reduce and exclude whole slush losses into pervious conformations. The choice of similar bridging agents will depend on the conformation characteristics. Generally, patches that are one- third to one- half the square root of the permeability in millidarcies( md) should be suitable to bridge similar conformations.