OfiTE 150-50 Instruction Manual

Differential Sticking Tester

Part No. 150-50

Instruction Manual

Updated 5/29/2009

Ver. 2.0

OFI Testing Equipment, Inc.

11302 Steeplecrest Dr. · Houston, Texas · 77065 · U.S.A.

Tele: 832.320.7300 · Fax: [phone] · www.ofite.com

©

Copyright OFITE 2011

Table of

Contents

Intro.......................................................................................................2

Description ...........................................................................................2

Components.........................................................................................3

Safety ...................................................................................................5

Test Procedure ..................................................................................6

Timed Filtration ................................................................................6

Fixed Cake Thickness....................................................................11

Disassembly.......................................................................................12

Theory.................................................................................................13

Example .........................................................................................15

Worksheet ......................................................................................16

Maintenance.......................................................................................17

Diagrams ...........................................................................................18

Full Unit ..........................................................................................18

Cell Assembly ................................................................................19

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ofite.com

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The OFITE Differential Sticking Tester measures the “Stuck Pipe Tendency
Coefficient” of drilling fluids, and also determines how effective lubricants or
treatments might be with any given drilling fluid. This coefficient takes into
account both the friction, or “stickiness”, of the filter cake, as well as the
amount of cake building that must occur in order to freeze or stick the pipe
in the hole. The coefficient is determined by running a Timed Filtration test.
By measuring the area of cake building during a test, the “Bulk Sticking
Coefficient” is obtained and read directly at the conclusion of the test. How
likely a given fluid will be to produce a stuck pipe situation and how effec­tive a given treatment may be, can be immediately determined on-site.

The unit is normally pressurized by a CO

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pressuring assembly, but any
nitrogen source will also work. If nitrogen is used, the tester apparatus
must be fitted with a suitable nitrogen regulator, gauges, valves, and high­pressure hoses. The standard test uses 477.5 PSI (3,291 kPa) applied to
a 200-mL stainless steel vessel. The unit includes both a flat-faced plate
and a plate of 12½" (31.75 cm) spherical radius, which simulates the pipe
inside the casing or collars in the borehole. For samples that adhere more
to the plate than to the filter paper, stainless steel micro-corrugation disks
are provided. For convenience a stainless steel carrying case is available
as an optional item.

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ofite.com

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Description

Intro

Components

#130-10-52 Jam Nut, 3/8-24, Qty: 2
#142-56 O-ring
#150-52 Neoprene Gasket
#150-53 Plastic Gasket
#150-54 Torque Wrench
#150-55 Spanner Wrench
#150-56 Test Cell O-ring
#150-57

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⁄16" Socket with 3⁄8" Drive
#150-58 Torque Plate; Flat Bottom
#150-59 Torque Plate; Spherical
#153-16 Glass Graduated Cylinder; 25 mL ×

2

⁄10 mL

#170-04 CO2Pressurization Unit:

#143-02-10 CO

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Puncture Head Assembly

#143-03 Barrel for CO

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Cartridge
#170-08 Regulator
#170-20 Manifold Block
#170-32

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⁄8" × 1⁄8" NPT Male Needle Valve
#171-22 Retainer Pin
#171-34 1500-PSI Gauge; 2"; ¼" NPT Bottom

#170-13 Test Cell O-ring; Buna N
#170-15 Base
#170-16 Valve Stem; Qty: 2
#170-17 Valve Stem O-ring; Qty: 10
#170-19 2½" (6.35 cm) Filter Paper; Specially Hardened for Filter

Presses
#170-35 6" Adjustable Wrench
#170-44 ½" Rubber Foot; Qty: 4
#171-79 ¼" Hex Wrench

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ofite.com

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Optional:

Yoke for Fixed Cake Thickness Test - Special Order Only

#150-50-SP Spare Parts for #150-50:

#142-56 O-ring; Qty: 12
#143-02-13 O-ring for Puncture Pin Holder Assembly; CO

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Cartridge;

Qty: 6
#143-02-14 O-ring for Puncture Pin Holder Assembly; Qty: 4
#143-05 EZ Puncture CO

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Bulbs; 8-Gram; UN #1013; Package of

10; Qty: 30
#143-06 Safety Bleeder Valve
#143-07 Regulator Repair Kit for #143-00
#143-22 Gasket for Puncturing Pin; Qty: 12
#150-51 Locking Mesh Disc; Qty: 10
#150-52 Neoprene Gasket; Qty: 10
#150-53 Plastic Gasket; Qty: 8
#153-16 Glass Graduated Cylinder; 25 mL × 2/10 mL; Qty: 2
#170-13 Test Cell O-ring; Buna N; Qty: 4
#170-16 Valve Stem; Qty: 2
#170-17 Valve Stem O-ring; Qty: 20
#170-19 2½" (6.35 cm) Filter Paper; Specially Hardened for Filter

Presses; Qty: 5
#170-23 60-Mesh Screen; Qty: 8
#171-22 Retainer Pin; Qty: 2
#171-79 ¼" Hex Wrench

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ofite.com

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Safety

Nitrogen must be supplied in an approved Nitrogen Gas Cylinder and
secured to meet safety standards. Do not use nitrous oxide cartridges as
pressure sources.

Due to the high pressures involved in this test, extreme care must be exer­cised at all times. All safety precautions must be met, especially in the cell
breakdown procedure after the filtration procedure has been completed.

Never transport CO

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bulbs or cartridges by airplane without proper packag-

ing. Cabin depressurization could cause them to explode.

Before pressuring, always check to be sure the regulator is in a closed
position by ensuring the T-screw is backed out and free turning. Insert and
puncture the CO

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cartridge by turning the barrel only a quarter turn past the
actual puncture point. Adjust the regulator to the desired pressure with the
regulator T-screw. With the Differential Sticking Tester, never exceed 500
PSI (3,450 kPa). When de-pressurizing, shut off the pressure supply, then
bleed off the system of pressure with the valve, and finally back out the
regulator T-screw.

OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: [phone] / Fax: [phone] / www.ofite.com

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