Texas Instruments TI-59 IMCO DrilMod

Date of introduction:  1979 Display technology:  LED-stick
New price:   Display size:  10 (8 + 2)
Size:  6.4" x 3.2" x 1.5"
 162 x 81 x 37 mm3
Weight:  8.5 ounces, 240 grams Serial No:  4722625
Batteries:  BP1A Date of manufacture:  wk 01 year 1982
AC-Adapter:  AC9131 Origin of manufacture:  USA (ATA)
Precision:  13 Integrated circuits:  TMC0501E, TMC0582, TMC0583, TMC0571, TMC0594, 4*TMC0598
 TMC0540 (ZA5511)
Logic:  AOS - 8 Pending Operations, 9 ()    
Memories:  0-60    
Program steps:  480-0 Courtesy of:  Joerg Woerner

The innovative TI-59 was the perfect base for a lot of customized calculators. The idea behind these products was the novelty of the Solid State Software Modules™ with up to 5000 program steps.

The IMCO "DrilMod" application was developed in 1979 by IMCO Services, a division of Halliburton Co., Houston for both the TI-58 and TI-59. The module contains applications in the areas of well control, annular and bit hydraulics, directional design, d-exponents, cost/ft, and drilling mud, a total of 16 programs in all:

Kick. Two separate programs: one to calculate kill mud weight and a standpipe pressure schedule fir circulating out invading fluid. And another kick program designed especially for directional wells and wells with tapered drill strings.
Well geometry. Processes hole drill string data into annular sections and stores results for use by other programs.
Hydraulics: Calculates bit pressure loss, hydraulic hp, impact force, jet velocity, and annular velocity.
OP hydraul. Makes nozzle size determinations.
ECD-S/S. Computes equivalent mud weight under circulating or tripping conditions.
Build and hold. Calculates final angle information and measured depth in design of “build and hold” directional wells.
d-exponent. Calculates d- and dc-exponents.
Cost/ft. Makes cost/ft calculations.
Rheology. Computes n- and k-values and calculates shear stresses at various shear rates.
Spot. Makes basic calculations needed for spotting around drill collars.
Mud report. Makes calculations required for completing the top of the API drilling mud report.
Solids (unweighted muds). Calculates solids content of unweighted muds and D/B-ratio.
Slip velocity. Calculates cuttings slip velocities.
Solids (weighted muds). Analyzes solids content of weighted muds.
Critical velocity. Calculates critical velocities in the annulus.

IMCO Services. Published in May 28, 1979 edition of Oil Gas Journal. © 1979 by PennWell Publishing Company.

Dismantling this TI-59 IMCO DrilMod calculator manufactured in January 1982 by Texas Instruments in Abilene, TX reveals a printed circuit board (PCB) with Integrated Circuits manufactured as late as Fall 1983, the calculator was obviously serviced.

Don't miss the Optimum Mud Hydraulics application, developed later in 1979 by Magnet Cove Barium Corporation - better known as Magcobar. IMCO released a second module (“BossMod” for well-control operations) before anybody else and later developed a third module (“MudMod”) for internally use only.

We know five different approaches of the module expansion:

Standard modules like the Master Library use only the small sticker
   above the A,B,C,D, and E keys.
Other modules like the Pool Water Analysis developed by Olin Corporation
   make use of a colorful keyboard mask.
Customized calculators like the USMC AV-8C calculator or insurance calculators
   sold by Allianz and others use special keyboard arrangements.
The CAL-Q-TAX calculator uses an extender instead the usual drop-in modules.
The Kodak Q-700 Program Adapter makes use of a snap-on cover with
   an individualized printing.

Information about the DrilMod, BossMod and MudMod applications provided by Mario Zamora. Thanks!

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© Joerg Woerner, August 8, 2009. No reprints without written permission.