Ex parte CHU

Board of Patent Appeals and Interferences

Jun 9, 1998

08275214 (B.P.A.I. Jun. 9, 1998)

Application for patent filed July 14, 1994. 1
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered
today (1) was not written for publication in a law
journal and (2) is not binding precedent of the Board.
Paper No. 13
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte WEI-CHUN CHU
____________
Appeal No. 97-1403
Application No. 08/275,2141
____________
ON BRIEF
____________
Before URYNOWICZ, HAIRSTON and CARMICHAEL, Administrative Patent
Judges.
HAIRSTON, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the final rejection of claims 1
through 3 and 5 through 9.
The disclosed invention relates to a method for validating
pressure test data obtained from a well that includes the step of
extending a pressure measurement instrument into the well to a
predetermined depth. The pressure measurement instrument has a
first gauge for measuring absolute pressure, and a second gauge
Appeal No. 97-1403
Application No. 08/275,214
2
for measuring a differential pressure over a predefined
differential measurement distance.
Claim 1 is illustrative of the claimed invention, and it
reads as follows:
1. A method for validating pressure test data obtained from
a well, said method comprising the step of:
(a) extending a pressure measurement instrument into said
well to a predetermined depth in said well, said pressure
measurement instrument having a pair of gauges, a first gauge for
measuring absolute pressure, and a second gauge for measuring a
differential pressure over a predefined differential measurement
distance;
(b) periodically sending a signal to said pressure
measurement instrument to initiate a measurement of pressure
inside said well;
(c) receiving a set of measurements resulting from said
signal sent in step (b), said set comprising an absolute pressure
measurement from said first gauge and a differential pressure
measurement from said second gauge;
(d) for each of said set of measurements obtained in
step (c), displaying said absolute pressure measurement on a
display device;
(e) for each of said set of measurements obtained in step
(c), using said differential pressure to determine a type of
fluid surrounding said pressure measurement instrument;
(f) when said type of fluid obtained in step (e) differs
from a type of fluid determined from an immediately previous set
of measurements, indicating a fluid boundary on said display
device; and
(g) validating any discontinuties [sic, discontinuities]
which may occur in said absolute pressure measurements by
reference to said fluid boundary.
The references relied on by the examiner are:
Appeal No. 97-1403
Application No. 08/275,214
3
Noik 3,184,965 May 25, 1965
Guimard et al. (Guimard) 4,455,875 June 26, 1984
Mattar, Critical Evaluation and Processing of Data Prior to
Pressure Transient Analysis, Society of Petroleum Engineers,
pages 709 through 721, 1992.
Claims 1 through 3 and 5 through 9 stand rejected under
35 U.S.C. § 103 as being unpatentable over Guimard in view of
Noik and Mattar.
Reference is made to the brief, final rejection and the
answer for the respective positions of the appellant and the
examiner.
OPINION
We have carefully considered the entire record before us,
and we will reverse the obviousness rejection of claims 1 through
3 and 5 through 9.
We agree with the appellant’s assessment of the teachings of
Guimard (Brief, pages 5 and 6), Noik (Brief, page 6), and Mattar
(Brief, pages 6 through 8). The pressure measurement sonde in
Guimard uses a pressure and temperature detector 18 in unison
with a reference detector 20 that only measures temperature. By
subtracting the temperature reading obtained by detector 20 from
the pressure and temperature readings obtained by the detector 18
the pressure measurement sonde yields an absolute pressure value
of the surrounding medium in the oil well. The three diaphragms
Appeal No. 97-1403
Application No. 08/275,214
4
18 through 20 in Noik form the major sensing apparatus in a
differential pressure sensing device that determines the nature
of fluids filling a well at various depths. Mattar teaches
that rising and falling liquid levels in a shut-in well can
cause errors in interpreting pressure measurements (page 711,
column 2), and that at least two gauges must be used during a
test for proper pressure readings (page 715, column 2).
According to the examiner (Final rejection, page 4), it
would have been obvious based upon the teachings of Mattar to
provide Guimard with a differential pressure gauge as taught by
Noik because “as taught by Mattar, density changes caused by
fluid discontinuities are one source of misdiagnosis in pressure
data taken in a shut in well and to account for this source of
error by employing the apparatus of Noik to determine the type of
fluid surrounding the instrument and any change therein as a
criteria for judging the soundness of absolute pressure
measurements would assure that such fluid discontinuities are
properly treated.”
Although Mattar teaches that at least two gauges must be
used for proper pressure measurements, this reference neither
teaches nor would it have suggested to one of ordinary skill in
the art the use of a differential pressure gauge in combination
Appeal No. 97-1403
Application No. 08/275,214
5
with an absolute pressure gauge. The appellant correctly
concluded (Brief, page 8) that “one of ordinary skill in the art
in the possession of Mattar would only be led to modify the
disclosure of Guimard et al. by employing a minimum of two
absolute pressure recorders in tandem and plotting the absolute
pressure recorded by each device.” In other words, Mattar “does
not disclose utilizing pressure recorders which have both an
absolute and a differential pressure gauge” (Brief, page 9).
Accordingly, we agree with appellant’s argument (Brief, page 10)
that the examiner has resorted to “improper hindsight analysis”
to demonstrate the obviousness of the claimed invention. The
obviousness rejection is reversed.
Appeal No. 97-1403
Application No. 08/275,214
6
DECISION
The decision of the examiner rejecting claims 1 through 3
and 5 through 9 under 35 U.S.C. § 103 is reversed.
REVERSED

STANLEY M. URYNOWICZ, Jr. )
Administrative Patent Judge )
)
)
)
) BOARD OF PATENT
KENNETH W. HAIRSTON ) APPEALS
Administrative Patent Judge ) AND
) INTERFERENCES
)
)
)
JAMES T. CARMICHAEL )
Administrative Patent Judge )
Appeal No. 97-1403
Application No. 08/275,214
7
Patent Department
Marathon Oil Company
P.O. Box 269
Littleton, CO 80160
KWH/jrg
APPEAL NO. 97-1403 - JUDGE HAIRSTON
APPLICATION NO. 08/275,214
APJ HAIRSTON
APJ CARMICHAEL
APJ URYNOWICZ
DECISION: REVERSED
Typed By: Jenine Gillis
DRAFT TYPED: 23 Dec 98
FINAL TYPED: