Safety In The Workplace

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GEO Drilling Fluids, Inc. ! P.O. Box 1478 ! Bakersfield, CA 93302

Telephone (661) 325-5919 ! FAX (661) 325-5648 !1-800-GETSGEO ! [email protected]

Drilling Fluids, Inc.

SAFETY

O

n a positive note, we have done a good job of eliminating or controlling workplace safety inci-dents and injuries. Because of this safety record our Workers Compensation insurance rates have not gone up for the past two years.

On a negative note, we have done a very poor job of eliminating or controlling vehicular accidents. In 1998-1999 we not only had a multitude of minor accidents (those costing less than $3000.00), but also a large number of major accidents (costing more than $20,000.00 each).

The major accidents can and have included compensatory damages to injured parties involved in our collisions.

All to frequently these accidents have been our fault. Almost always the cause was inattention.

Based upon our performance our automobile insurance carrier sought to double our premiums. Fortunately, another carrier was willing to assume the risk for only a 40% increase. However, our broker assured us that a similar performance this year would guarantee us a 100% increase next year. Since the increase is approximately 30% of the Profit Sharing contribution it would be in all of our best interests to drive safely and to encourage others in the company to do the same.

In order to eliminate the opportunity for fraudulent

WHAT DO

YOU

WANT IT TO BE?

1. Why should you wash off a shaker?

2. Flow in the annulus should be a) laminar, b) turbulent, c) plug, d) depends.

3. The most effective product for viscosity problems in a water based mud is: a) Desco CF, b ) Omnipol II, c) Water, d) Cypan.

ANSWERS ON PAGE 4

WIRE LINE RETRIEVAL CORING

TECHNOLOGY SHOWS PROMISE

Nenkov, Bednarz, and Nedyalkov Oil & Gas Journal 8/2/99

T

he ability to use slim-hole, continuous corecovery technologies incorporating whirling re-trievable core bits, core barrel, and downhole shock absorber offers a new technique for drilling operations.

Continued on page 2

claims I have asked in the past and do so again, that all drivers of company vehicles purchase a disposable camera to be stored in the vehicle. If you have an accident, take pictures of your vehicle, their vehicle, the other party, and the accident scene!

Our new auto insurance carrier has loaned us three Video of material for mandatory review. Andy will set up a system to pass them around. Please review them in a serious manner. Along with the videos there is a small Driver's Handbook for you to keep.

Jim Clifford

"Ships are safe in the harbor, but that's not what ships are made for. The same is true of the human spirit. Don't ever be afraid to take chances, reach for the stars, or take a stand on what you believe in."

TECHNICAL SERVICES NEWS LETTER

Volume III, Number 7 November 25, 1999

It is the mark of those with the true human evolutionary spirit to each day seek to learn more about their world, do their tasks better than the day before, and to never believe that they have achieved the ultimate.

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Page 2

TECHNICAL SERVICES NEWS LETTER Volume III, Number 7 November 25, 1999

Page 2

Wire Line... continued from page 1

This is particularly important for drilling operations in remote, difficult, and ecologically vulnerable regions.

Slim-hole drilling saves costs by reducing the hole diameter, resulting in the decreased need for steel, drilling fluid, rig power, and transportation require-ments. This technology can be used with high-technology, automated slim-hole drilling rigs or less-expensive mining exploration rigs.

Investigative results by the University of Mining & Geology and Geologoprouchvatelno Predpriatie, both located in Sofia, Bulgaria,

show that the application of a small slim-hole drilling rig may provide overall savings of 25-65% when compared to conventional drilling rigs. Additionally, such rigs can minimize environmental damage by reducing drilling wastes three fold as com-pared with a conventional drilling rig.

Synergism

The transition to a small-diameter drilling system allows the implementation of the nonstop core drilling approach, widely applied in the mining industry. Thus, the implementation of a simple and reliable wire line-retrievable core-bit system may offer a complete change of attitude towards the use of this technology.

Under certain conditions, the usage of the wire line complex has two primary advantages.

? Wire line retrievable cores save significant trip time.

? Wire line retrievable bits allow for unanticipated changes in lithology. The design of a universal core bit that works equally well in various geological formations and structures is not possible, despite improvements in drill-bit technologies. With a wire line system, however, it becomes feasible to change out drill bits quickly.

A working system, successfully used in Bulgaria, shows the promise of this wire line technology, having drilled a section of more than 1,000 m (3281') using a 76-mm (3") wire line retrievable core bit, wire line-retrievable core barrel, and a shock absorber.

The shock absorber, an essential component of the wire line complex, helps to dampen the system from the effects of axial shocks.

This system had the following attributes:

? The drillstring remains the same from the

begin-ning of the coring to TD.

? The entire drillstring contains the same inside di-ameter throughout.

? Tripping out worn drill bits and running new ones is conducted through the drillstring.

? The wire line-retrievable core barrel operates without a hanger, requiring very little force to release itself.

? The shock absorber is situated at the bottom of the drill pipe string.

? Tripping operations are entirely eliminated.

Design and action

The wire line-retrievable core-bit consists of a body, renewable cutting devices, and working parts. The multifunctional body con-nects with the transport device, the inner core bar-rel. It also provides orienta-tion capabilities.

Latching up

The retrievable core barrel is run down hole under gravitation or by using an overshot. Once it reaches the end of the drillstring, the instrument body automatically orients itself by aligning the reamer with the drillstring. The working elements are fixed in a working position by the inner core barrel that also self actuates into a working position.

The coring elements, made of a special design, can be quickly replaced. In addition, the cutting mecha-nism, made of diamonds or PDC disks, can be customized and adapted to specific work conditions.

The lower row of rollers plays the part of a hanger ring while the upper row of rollers adjusts the inner core barrel towards the outer core barrel. Retrieval of a worn core bit is performed either by wire line retrieval of the core barrel or by lowering an overshot. When bit retrieval is not necessary, the core barrel is pulled out by itself.

Conclusion

The application of retrievable tools has great promise for deep hole drilling. Savings in trip time could more than offset added costs and lowered performance of tools. We should look forward to the appearance of this Eastern technology here in the West. What appears to be a primitive core head (Figure 1) could be upgraded to a PDC or Diamond cutter for hard formations.

Figure 1. Retrievable Core Bit

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TECHNICAL SERVICES NEWS LETTER

WHAT DOES A BIT LOOK LIKE?

HardRokTM _{tri-cone "button" bits (left)}

were developed to extend bit life while in-creasing penetration rates. BlackTrax Polycrystalline Diamond Compact (PDC) bit (right), was designed to improve steer-ability in directional and deviated applica-tions.

DOWCO's newest bit, the TM-277 is a PDC designed for heavily interbedded formations and features maximized face volume to improve hole cleaning.

RockBit Inter-national developed the One Cone bit for slim hole drill-ing. The single larger cone over-comes problems with having three cones with tiny bearings and teeth on a 6" diameter or even smaller bit.

Deep fluid channels and aggressive tilt to the cutters make this GeoDiamond PDC bit better able to deal with geologically young formations con-taining very reactive and sticky clays. Combining the ad-vances of the SpeedReamerTM

bi-center bits with the de-sign features of the LoTorqueTM_steerable

bits, Diamond Products International says it's new PDC SpeedDrillTM

reaming bit is designed to use less energy in drilling an oversized hole, leaving more en-ergy to drill ahead and improving ROP and bit life.

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Page 4

TECHNICAL SERVICES NEWS LETTER

T

he Mud Cleaner was developed to allow the use of a Desilter in a weighted mud without losing all the Barite. In more modern systems, especially where disposal costs are high, the Mud Cleaner is utilized to reclaim the liquid discharged by the hydrocyclones. In an unweighted mud a very fine screen (250 mesh or finer) can be run to remove very fine solids (down to 65 micron). In a weighted mud 150 mesh or 175 mesh screens will allow most of the Barite to be retained in the system.

The basic problem with Mud Cleaners is that they don't remove the truly fine solids (less than 10 micron) that contribute the most to viscosity. They do not remove any clay size particles (2 micron or less). In a sense, they are merely Desanders in that the material they remove is sand sized when they are being run in a weighted system. While this is important in controlling weight and as a backup to the shakers to protect the pumps from sand erosion, it does little to control yield point viscosity.

When Barite is freshly mixed, especially in large quantities, a substantial portion will be removed by 150 mesh shaker screens on the mud cleaner. This occurs due to a phenomenon known as "piggy backing." "Piggy backing" occurs due to the physical mass of solids on the screen whereby some solids ride across others. Barite is initially ground so that 95% will pass through a 200 mesh screen. This, of course, means that it is OK for 5% to be larger than 200 mesh. 5% of a pallet of Barite is 2 sacks! Once the mud has been sheered through the bit a couple of times this problem is usually reduced and only a small fraction

Continued on page 5

W

hen we were all writing mud reports with carbon paper it was a lot easier to pay attention to what we were saying. Still, there were times when we made calculation errors that resulted in reporting values that are just plain impossible.

Now that we are using computers more and more, it is even easier to report erroneous information. An old computer saying is GIGO (garbage in - garbage out). Computer programs tend to be pretty stable and to process the data that you enter in the same way every day. If you input errors, like 135.4' instead of 1354', the computer doesn't notice that you were at 800' yesterday and ought to be deeper, it just calculates your volumes and bottoms up with the new (and wrong) depth. That's why it is so important to review the report before you turn it over to the

ANSWERS TO

WHAT DO

YOU

WANT IT TO BE? 1. There are many answers to this question. If you

will write (or call) with your favorite answer, I'll put

to-gether a little article for the next news letter. 2. The ideal flow is dependent on the formations drilled, angle of the hole, and other factors unique to

the situation. 3. c) Water

IS THE MUD CLEANER THROWING AWAY ALL MY BARITE?

PLEASE READ WHAT YOU WRITE!

company man, pusher, roughnecks and/or mud loggers.

Careful reading of the mud report also means understanding all the details that are being reported. I was recently surprised to discover that the critical velocity that we have been reporting for Heavy Wall Drill Pipe has been wrong for some time. Tom noticed that it was different from the drill pipe critical velocity. The error is mine, and like everyone else, I missed it last week when I was on a rig. It is a simple cell reference that I can fix over the phone. (Please call and let me help you fix it). The bigger problem is that no one has noticed before that what they were reporting didn't make sense.

So read what you write before you hand it in and keep yourself and GEO from looking foolish.

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? Catch a representative sample of the solids discharge from the Mud Cleaner screen.

? A small amount of water may be added to make the material easier to weigh, but not so much that significant settling occurs.

? Weigh the solids in the mud scale. Use care to insure that all air bubbles are removed and all sand is clear from between the cup and the lid.

? Using the same material that was weighed, run a retort analysis. Use the same precautions when filling the retort as described above for the mud balance. Do not add any more water at this point!

? Record mud weight in ppg, % solids, % oil, and % water.

? Calculate the density of the solids:

Density = (((Mud Weight ÷ 8.33) x 100) - % Water - (% Oil x 0.84)) ÷ % Solids

? Calculate the percent Barite:

% Barite = ((Density x 100) - 260) ÷ 1.6

? This calculation can be done on the computer with GEO’s Mud Report program. Just enter the density of the cuttings as mud weight and the retort results. Read the % Barite on the Mud Report.

In deciding haw much Barite is acceptable it is important to remember that 5% of fresh Barite will be removed with a 200 mesh screen. Some Barite loss due to "piggy backing" will occur and cannot be prevented. Changing screen sizes to a coarser mesh

Mud Cleaners continued from page 4

of the Barite should be lost. If the screens are blinded, carrying too much fluid for their area, or if the

viscosity of the mud is too high, a large amount of Barite may still be lost.

It is sometimes important to quantify the amount of Barite that is being lost over the Mud Cleaner. The proper way to do this is as follows:

may be a solution. Shutting down the Mud Cleaner for a period is also an acceptable solution, especially in slow drilling. These decisions are all subjective and should be made in consultation with the customer taking into account the economic pros and cons.