The document describes an experiment using a Marsh funnel viscometer to measure the viscosity of a drilling mud sample. Key details include: - A Marsh funnel viscometer is used to quickly measure fluid viscosity by timing how long it takes 1 liter of fluid to flow through the funnel's orifice. - The experiment involves preparing a 500cc mud sample at 8.6 ppg density and measuring the time in seconds for it to flow through the calibrated Marsh funnel to the 1 quart level. - The funnel viscosity measurement provides a way to monitor changes in mud properties that could require corrective action to control factors like viscosity, fluid flow properties, and solids suspension.

1. Koya university
Faculty of engineering
Petroleum department
Drilling engineering laboratory
(Marsh funnel)
Dec.10th
.2015
Lab EXP.(4)
Supervised By Prepared By
Mr. Pishtiwan bakhtiar star m.
Submitted on: Dec. 17th
2015

2. Table of Contents
Objective…………………………………………………………………………………………………………3
Abstaract…………………………………………………………………………….4
Theory ……………………………………………………………………………….5
Introduction of experiment …………………………………………………………..6
Calibration ……………………………………………………………………………7
Procedure ……………………………………………………………………………..8
Calculation ……………………………………………………………………………9
Discussion………………………………………………………………………….....10
Reference ……………………………………………………………………………..11

3. Objective
The marsh funnel viscometer is a simple device
used for quick measurements of fluid viscosity.

4. Abstract
Viscosity is a measurement of a fluids resistance to flow:the
greater the resistance, the higher the viscosity. (Musaed,
2005).
Based on a method published in 1931 by H.N.Marsh,a Marsh
cone is a flow cone with an aspect ratio of 2:1 and a working
volume of at least a litre. A Marsh funnel is a Marsh cone
with a particular orifice and a working volume of 1.5 liters.
(H. N. Marsh (1931))
The marsh funnel viscosity respectively the funnel flow time
is the ratio of the speed of the sample fluid as it passes fluid
through the orifice to the amount of force that is causing the
to flow. The marsh funnel viscosity is reported as the number
of seconds required for 1000 cm³ of sample fluid to flow out
of a full marsh funnel.(M. J. Pitt (2000))
The marsh funnel is made of break-resistant plastic and has
a fixed orifice half the cone avoids the orifice getting blocked
by greater particles. The high-impact plastic measuring cup
is designed specifically for use with marsh funnel
viscometer and has scales in cubic centimeter and fluid
ounces.(A. W. McCray & F. W. Cole (1979))

5. Theory
A conical-shaped funnel, fitted with a small-bore tube on the
bottom end through which mud flows under a gravity head. A
screen over the top removes large particles that might plug the
tube. In the test standardized by API for evaluating water-base and
oil-base muds, the funnel viscosity measurement is the time (in
seconds) required for one quart of mud to flow out of a Marsh
funnel into a graduated mud cup. Funnel viscosity is reported in
seconds (for a quart). Water exits the funnel in about 26 seconds.
This test was one of the earliest mud measurements for field use.
Simple, quick and fool-proof, it still serves as a useful indicator
of change in the mud by comparing mud-in and mud-out sample
funnel viscosities (H. N. Marsh (1931)) .
Marsh Funnel readings are only general measurements, but the
frequent reporting of the Marsh Funnel Viscosity will alert the
mud engineer to sudden changes in the mud viscosity that could
require corrective action. The Marsh Funnel(M. J. Pitt (2000))
viscosity should be as small as possible to limit friction pressure.
However a certain amount of viscosity is required to improve the
solids carrying capacity of the mud. If viscosity is too small, the
mud may be unable to suspend drilled solids at the desired pump
rate. This requires the pumps to be run faster to continue to
circulate drilled solids out of the well. If viscosity is too high, an
excessive pump pressure will be required to circulate the mud at
the desired rate (A. W. McCray & F. W. Cole (1979

6. Calibration
Fill the funnel to the bottom of the screen (1500ml) with
water at 70F (plus or minus 0.5F) time of out flow of the
quart (946ml) should be 26 seconds plus or minus
1/2second.

7. Procedure
1-prapare 500cc mud a density of 8.6 ppg
2-With the funnel in an upright position, cover the orifice with a
finger and pour the freshly collected mud sample through the screen
into a clean, dry funnel until the fluid
level reaches the bottom of the screen (1500 ml).
3- Immediately remove the finger from the outlet and
measure the time required for the mud to fill the receiving
Vessel to the 1-quart (946 ml) level .
4- Report the result to the nearest second as Marsh Funnel viscosity
at the temperature of the measurement in degrees Fahrenheit or
Centigrade.
.

8. DISCUSION
Q1- What’s the benefit of marsh funnel in the field?
A1-It provide a short way to realize any conversion in viscosity
of drilling mud.
Q2-descripe useful screen over the top funnel (mesh) ?
A2- screen over the top removes large particles that might plug the
tube.
Q3-could you describe a main cause get error at marsh funnel
test ?
A3-
in case if we not doing this experiment in standard conditional
the temperature is (70 F0
) .
And in case if the throat of funnel not work properly by
plugging a large particles or another reason.
Q4- Whats the main function of viscosity in mud ?
A4- viscosity should be as small as possible to limit friction
pressure. However a certain amount of viscosity is required to
improve the solids carrying capacity of the mud. If viscosity is
too small, the mud may be unable to suspend drilled solids at
the desired pump rate. This requires the pumps to be run
faster to continue to circulate drilled solids out of the well. If
viscosity is too high, an excessive pump pressure will be
required to circulate the mud at the desired rate.

9. References
1. H. N. Marsh (1931)Trans AIME vol 92 pp 234-251 "Properties and
Treatment of Rotary Mud"
2. A. W. McCray & F. W. Cole (1979) Oil Well Drilling Technology
University of Oklahoma Press ISBN 0-8061-0423-6
3. M. J. Pitt (2000) SPE Drilling and Completion vol 15 no1 pages 3-6
“The Marsh Funnel and Drilling Fluid Viscosity: A New Equation for
Field Use”
4. 4-Rabia, H. (2001) Well Engineering and Construction. Halesowen:
ENTEC
5. Growcock, F. and Harvey, T. (2005) „Drilling Fluids‟ in ASME,
Shale Shaker Committee. Drilling Fluids Processing Handbook.
Oxford: Gulf Professional Publishing, pp. 15-68.