oSIST prEN ISO 15136-1:2025

SLOVENSKI STANDARD
01-november-2025
Industrija za predelavo nafte in zemeljskega plina - Vijačni črpalni sistemi za
prečrpavanje na površino - 1. del: Črpalke (ISO/DIS 15136-1:2025)
Petroleum and natural gas industries - Progressing cavity pump systems for artificial lift -
Part 1: Pumps (ISO/DIS 15136-1:2025)
Erdöl- und Erdgasindustrie- Exzenterschneckentiefpump-Fördersysteme - Teil 1:
Pumpen (ISO/DIS 15136-1:2025)
Industries du pétrole et du gaz naturel - Pompes de fond à cavités progressantes pour
activation des puits - Partie 1: Pompes (ISO/DIS 15136-1:2025)
Ta slovenski standard je istoveten z: prEN ISO 15136-1
ICS:
75.180.10 Oprema za raziskovanje, Exploratory, drilling and
vrtanje in odkopavanje extraction equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 15136-1
ISO/TC 67/SC 4
Petroleum and natural gas
Secretariat: ANSI
industries — Progressing cavity
Voting begins on:
pump systems for artificial lift —
2025-09-16
Part 1:
Voting terminates on:
2025-12-09
Pumps
Industries du pétrole et du gaz naturel — Pompes de fond à
cavités progressantes pour activation des puits —
Partie 1: Pompes
ICS: 75.180.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
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USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
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POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 15136-1:2025(en)
DRAFT
ISO/DIS 15136-1:2025(en)
International
Standard
ISO/DIS 15136-1
ISO/TC 67/SC 4
Petroleum and natural gas
Secretariat: ANSI
industries — Progressing cavity
Voting begins on:
pump systems for artificial lift —
Part 1:
Voting terminates on:
Pumps
Industries du pétrole et du gaz naturel — Pompes de fond à
cavités progressantes pour activation des puits —
Partie 1: Pompes
ICS: 75.180.10
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document has not been edited by the ISO Central Secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2025
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
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BE CONSIDERED IN THE LIGHT OF THEIR
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NATIONAL REGULATIONS.
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TO SUBMIT, WITH THEIR COMMENTS,
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NOTIFICATION OF ANY RELEVANT PATENT
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Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 15136-1:2025(en)
ii
ISO/DIS 15136-1:2025(en)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Abbreviated terms and symbols . 8
5 Functional specification . 9
5.1 General .9
5.2 PCP type description .9
5.3 Functional requirements . .10
5.3.1 Application parameters.10
5.3.2 Environmental compatibility .11
5.3.3 Compatibility with related well equipment and services . 12
5.4 Design validation . 13
5.5 Product functional evaluation .14
5.6 Quality control grades .14
5.7 Additional documentation .14
5.8 Additional requirements .14
6 Technical specification . 14
6.1 General .14
6.2 Technical characteristics .14
6.3 Design criteria . 15
6.3.1 General . 15
6.3.2 Metals . 15
6.3.3 Rotor coating or surface treatments . 15
6.3.4 Stator elastomer and bond system .16
6.3.5 Inner surface treatment of metal stator .16
6.4 Dimensional information .16
6.4.1 Rotor-stator fit .16
6.4.2 Dimensional limits .16
6.5 Performance ratings .17
6.5.1 Volume capability .17
6.5.2 Pressure and head rating . . .17
6.5.3 Design performance curves .17
6.5.4 Volumetric efficiency .17
6.5.5 Design pump speed, torque and power .17
6.5.6 Maximum pump intake gas volume fraction .18
6.6 Design verification .18
6.7 Design validation .18
6.8 Functional evaluation requirements .18
6.9 Allowable design changes .18
6.10 Scaling of design validation .19
7 Supplier/manufacturer requirements . 19
7.1 General .19
7.2 Documentation and data control .19
7.2.1 General .19
7.2.2 Design documentation .19
7.2.3 Delivery documentation . 20
7.2.4 Operator's manual. 20
7.2.5 Certificate of compliance . 20
7.2.6 Product data sheet . 20
7.2.7 Elastomer data sheet .21

iii
ISO/DIS 15136-1:2025(en)
7.3 Product identification .21
7.4 Quality . 22
7.4.1 General . 22
7.5 Raw materials certification . 23
7.6 Additional processes applied to components . 23
7.6.1 Documentation. 23
7.6.2 Coatings .24
7.6.3 Welding .24
7.6.4 Heat treating .24
7.7 Traceability .24
7.8 Calibration systems .24
7.9 Examination and inspection . 25
7.9.1 General . 25
7.9.2 The tube of stator . 25
7.9.3 Stator elastomer. 25
7.9.4 Stator phasing alignment . 26
7.9.5 Rotor coating thickness. 26
7.9.6 Rotor surface finish .27
7.9.7 Phasing alignment of welded rotor .27
7.9.8 Visual inspection .27
7.9.9 Weld .27
7.9.10 Core deflection . 28
7.9.11 Component dimensional inspection . 28
7.10 Manufacturing non-conformance . 30
7.11 User/purchaser complaint returns . 30
7.12 Product functional testing . 30
8 Repair .31
9 Shipping, handling and storage .31
9.1 General .31
9.2 Preparation for shipment .31
9.3 Handling .31
9.3.1 Rotor .31
9.3.2 Stator.31
9.4 Storage .32
Annex A (normative) Requirements for progressing cavity pump elastomers .33
Annex B (normative) Design validation .37
Annex C (normative) Functional evaluation . 41
Annex D (informative) Optional information for PCP elastomer testing and selection .47
Annex E (informative) Installation guidelines .57
Annex F (informative) Operational guidelines .60
Annex G (informative) Supplemental information for PCP performance characteristics .67
Annex H (informative) Example user/purchaser PCP functional specification form .72
Annex I (informative) Analysis after use . 76
Annex J (informative) Selection and use of drive-string equipment in PCP applications .90
Annex K (informative) Repair and reconditioning .97
Annex L (informative) Auxiliary equipment .100
Bibliography .106

iv
ISO/DIS 15136-1:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 15136-1 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore structures
for petroleum, petrochemical and natural gas industries, Subcommittee SC 4, Drilling and production
equipment.
This second edition cancels and replaces the first edition (ISO 15136-1:2001), which has been technically
revised.
Added definitions of terms for equal-wall thickness stator and metal stator.
Added Technical specification for PCPs.
Added Supplier/manufacturer requirements for PCPs.
Revised the requirements for progressing cavity pump elastomers in Appendix A.
Revised the Hydraulic validation in Appendix B.
Revised the Pump bench test parameter requirements in Appendix C.
ISO 15136 consists of the following parts, under the general title Petroleum and natural gas industries —
Progressing cavity pump systems for artificial lift:
Part 1: Pumps
Part 2: Surface-drive systems
v
ISO/DIS 15136-1:2025(en)
Introduction
This part of ISO 15136 has been developed by users/purchasers and suppliers/manufacturers of progressing
cavity pumps and is intended for use in the petroleum and natural gas industry worldwide. This part of
ISO 15136 provides requirements and information to both parties in the selection, manufacturing, testing,
and using progressing cavity pumps as defined in the scope. Further, this part of ISO 15136 addresses
supplier requirements, which set the minimum parameters with which it is necessary that suppliers comply
to claim conformity with this part of ISO 15136.
This part of ISO 15136 provides grades of requirements for design validation, quality control and functional
evaluations allowing the user/purchaser to select each for a specific application. There are three grades of
design validation and quality control, and two grades of functional testing. Design validation grade V3 is
restricted to legacy products, the basic grade is V2 and the highest grade is V1. Quality control grade 3 is
the standard grade and grades 2 and 1 provide additional requirements. Functional evaluation grade F1
requires a hydraulic test of the PCP and grade F2 does not. The user/purchaser has the option of specifying
requirements supplemental to these grades.
It is necessary that the users of this part of ISO 15136 be aware that requirements above those outlined in
this part of ISO 15136 can be needed for individual applications. This part of ISO 15136 is not intended to
inhibit a supplier/manufacturer from offering, or the user/purchaser from accepting, alternative equipment
or engineering solutions. This can be particularly applicable where there is innovative or developing
technology. Where an alternative is offered, it is the responsibility of the supplier/manufacturer to clearly
and completely identify any variations from the requirements of this part of ISO 15136.

vi
DRAFT International Standard ISO/DIS 15136-1:2025(en)
Petroleum and natural gas industries — Progressing cavity
pump systems for artificial lift —
Part 1:
Pumps
1 Scope
This part of ISO 15136 provides requirements for the design, design verification and validation,
manufacturing and data control, performance ratings, functional evaluation, repair, handling and storage
of progressing cavity pumps for use in artificial lift in the petroleum and natural gas industry. This part of
ISO 15136 is applicable to those products meeting the definition of progressing cavity pumps (PCP) included
herein. Connections to the drive string and tubulars are not covered by this part of ISO 15136.
This part of ISO 15136 includes normative annexes that establish requirements for characterization and
testing of stator elastomer material, design validation and functional evaluation. Additionally, informative
annexes provide information for PCP elastomer selection and testing, installation, start-up and operation
guidelines, equipment selection and application guidelines, functional specification form, used pump
evaluation, drive string selection and use, repair and reconditioning procedures and auxiliary equipment.
Equipment not covered by the requirements of this part of ISO 15136 includes bottom-drive systems except
for the PCP components, drive-string components and auxiliary equipment such as tag bars, gas separators
and torque anchors. These items might or might not be covered by other International Standards. Surface-
drive systems are covered in ISO 15136-2.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 34-1, Rubber, vulcanized or thermoplastic — Determination of tear strength — Part 1: Trouser, angle and
crescent test pieces
ISO 37, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties
ISO 815-1:2008, Rubber, vulcanized or thermoplastic — Determination of compression set — Part 1: At ambient
or elevated temperatures
ISO 2977, Petroleum products and hydrocarbon solvents — Determination of aniline point and mixed aniline point
ISO 4662, Rubber, vulcanized or thermoplastic — Determination of rebound resilience
ISO 4666 (all parts), Rubber, vulcanized — Determination of temperature rise and resistance to fatigue in
flexometer testing
ISO 7619-1, Rubber, vulcanized or thermoplastic — Determination of indentation hardness — Part 1: Durometer
method (Shore hardness)
ISO 7743, Rubber, vulcanized or thermoplastic — Determination of compression stress-strain properties
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel

ISO/DIS 15136-1:2025(en)
ISO 11960, Petroleum and natural gas industries — Steel pipes for use as casing or tubing for wells
ISO 15136-2, Petroleum and natural gas industries — Progressing cavity pump systems for artificial lift — Part
2: Surface-drive systems
ISO 15156 (all parts), Petroleum and natural gas industries — Materials for use in H S-containing environments
in oil and gas production
API Spec 11B, Specification for Sucker Rods
ASTM D412, 06ae2, Standard Test Methods for Vulcanized Rubber and Thermoplastic Elastomers — Tension
ASTM D471, Standard Test Method for Rubber Property — Effect of Liquids
ASTM D429-08, Standard Test Methods for Rubber Property — Adhesion to Rigid Substrates
ASTM D575, Standard Test Methods for Rubber Properties in Compression
ASTM D611-07, Standard Test Methods for Aniline Point and Mixed Aniline Point of Petroleum Products and
Hydrocarbon Solvents
ASTM D623, Standard Test Methods for Rubber Property — Heat Generation and Flexing Fatigue in Compression
ASTM D624, Standard Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic
Elastomers
ASTM D2240-05, Standard Test Method for Rubber Property — Durometer Hardness
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
actual capacity per rpm
volumetric capability determined through functional testing for a specific product
Note 1 to entry: “rpm” has been retained in this term on the basis that it is part of an established industry terminology.
However, it is deprecated by ISO as a unit, in which case it is rendered as the accepted form “r/min.”
3.2
applied torque
torque that is applied to the rotor of the PCP by the drive system
3.3
artificial lift system
assembly of equipment used to transport fluid from a subsurface formation to surface, which may include
pump, drive string, prime mover and production tubing
3.4
auxiliary equipment
equipment or components that are outside the scope of this part of ISO 15136 and that are typically selected
and/or installed by the user/purchaser
EXAMPLE Tag bars, gas separators and torque anchors.

ISO/DIS 15136-1:2025(en)
3.5
bottom-drive system
PCP drive system utilizing a downhole prime mover
3.6
casing
pipe extending from the surface and intended to line the walls of a drilled well
3.7
casing size
nominal casing OD as specified in ISO 11960
3.8
core deflection
radial offset of the stator cavity centre-line from the stator tube centre-line
3.9
corrosive environment
operating environment where the combination of temperature and chemical agents causes degradation of
the equipment
3.10
design validation
process of proving a design by testing to demonstrate conformity of the product to design requirements
3.11
design verification
process of examining the premise of a given design by calculation, comparison or investigation, to
substantiate conformity with specified requirements
3.12
dogleg severity
localized wellbore curvature
3.13
differential pressure
difference between pump intake and discharge pressures
3.14
downhole capacity per rpm
volumetric capability estimated through calculations and downhole conditions
Note 1 to entry: “rpm” has been retained in this term on the basis that it is part of an established industry terminology.
However, it is deprecated by ISO as a unit, in which case it is rendered as the accepted form “r/min.”
3.15
drive string
device transmitting power (usually sucker rods) between the surface drive system and the PCP
3.16
engaged cavities
number of full cavities created by the interaction between the rotor and stator
3.17
failed item
any item that has failed
3.18
failure
termination of the ability of an item to perform a required function

ISO/DIS 15136-1:2025(en)
3.19
failure descriptor
apparent, observed effect of failure (of a failed item)
3.20
failure cause
circumstances during design, manufacture, or use which have led to a failure
3.21
flow rate
volume of fluid pumped per unit of time
3.22
friction torque
resistance to rotation of the drive string (inside the tubing) and the rotor (inside the stator) that is dependent
upon factors including (but not exclusive to) well depth and trajectory, pump geometry and interference fit
between rotor and stator, and stuffing box characteristics
3.23
function
operation of a product during service
3.24
functional specification
features, characteristics, process conditions, boundaries and exclusions defining the performance and use
requirements of the equipment
3.25
functional test
test performed to confirm proper equipment operation
3.26
grade
category or rank given to different requirements for quality or design validation
3.27
head rating
pressure rating expressed in terms of equivalent water column
3.28
hydraulic torque
torque induced by the differential pressure across the pump
3.29
insertable pump
PCP where the stator is run into the well through the production tubing
3.30
item
any part, component, device, subsystem, functional unit, equipment or system that may be individually
considered
3.31
manufacturing
process and action performed by an equipment supplier/manufacturer that are necessary to provide finished
component(s), assembly(ies) and related documentation, that fulfil the requests of the user/purchaser and
meet the standards of the supplier/manufacturer
Note 1 to entry: Manufacturing begins when the supplier/manufacturer receives the order and is completed at the
moment the component(s), assembly(ies) and related documentation are surrendered to a transportation provider.

ISO/DIS 15136-1:2025(en)
3.32
maximum operating speed
maximum operating speed for the pump as specified by the supplier/manufacturer
3.33
maximum operating temperature
maximum operating temperature for the pump as specified by the supplier/manufacturer
3.34
model
equipment with unique components and operating characteristics which differentiate it from other
equipment of the same type
3.35
no-turn tool
prevents the PCP stator and/or tubing from backing off due to rotational torque caused by the interference
fit between the rotor and stator
3.36
nominal capacity per rpm
published volumetric capability based on theoretical calculations and adjusted for commercial purposes
Note 1 to entry: “rpm” has been retained in this term on the basis that it is part of an established industry terminology.
However, it is deprecated by ISO as a unit, in which case it is rendered as the accepted form “r/min.”
3.37
non-conformance
non-fulfilment of a specified requirement, such as the divergence of equipment, part, practice or procedure
from an established standard
3.38
operator
user of the equipment
3.39
operator's manual
publication issued by the supplier/manufacturer that contains detailed data and instructions related to the
design, installation, operation and maintenance of equipment
3.40
operating environment
set of conditions to which the product is exposed during its full life cycle
3.41
orbit tube
section of oversized production tubing installed immediately above the stator
3.42
PCP geometry
unique combination of pitch, eccentricity and diameter
3.43
performance ratings
ratings for the hydraulic performance of the pump
3.44
pressure rating
rated differential pressure capacity
3.45
primary failed item
failed item within the PCP responsible for initiating the failure of the PCP

ISO/DIS 15136-1:2025(en)
3.46
prime mover
motor (typically hydraulic, electric or internal combustion) providing the torque to rotate the pump rotor
3.47
progressing cavity pump PCP
pump installed in a well consisting of a stator and rotor whose geometry of assembly is such that it creates
two or more series of lenticular, spiral, separated cavities
3.48
Equal-wall thickness PCP
A PCP that has a uniform and equal cross-sectional thickness of the elastomer along the axial direction and
is also referred to as an even-wall PCP.
3.49
metal PCP
a
A PCP with the inner surface processed from metallic materials
Note 1 to entry: a: see Figure 4
3.50
qualified part
part manufactured under an authorized quality assurance programme and in the case of replacement,
produced to meet or exceed the performance of the original part
3.51
qualified person
individual with characteristics or abilities gained through training or experience or both as measured
against established requirements, such as standards or tests that enable the individual to perform a required
function
3.52
reason for pull
motive for the pump being pulled from the well
3.53
redress
any activity restricted to the replacement of qualified parts
3.54
repair
any activity beyond the scope of redress that includes disassembly, re-assembly and testing with or without
the replacement of qualified parts and may include machining, welding, heat treating or other manufacturing
operations that restore the equipment to its original performance
3.55
required function
function or a combination of functions of an item, which is considered necessary to provide a given service
3.56
rotor
helical, contoured shaft
3.57
rotor phasing alignment jig
short segment of material moulded to match the rotor profile
3.58
substantial design change
change to the design, identified by the supplier/manufacturer, that affects the performance of the product in
the intended service condition

ISO/DIS 15136-1:2025(en)
3.59
size
relevant dimensional characteristics of the equipment as defined by the supplier/manufacturer
3.60
slugging
well production characterized by non-homogeneous flow
3.61
stator
segment of tube with an internal helical contoured surface which meshes with a rotor to create a series of
lenticular cavities along the length of the tube.
3.62
stator phasing alignment jig
short segment of material moulded to match the stator core profile
3.63
swelling process
volume increase of an elastomer when a fluid diffuses into the material due to physical interactions between
fluid and the elastomer
3.64
tag bar
assembly attached to the bottom of the stator that limits the distance the rotor may extend past the end of
the stator
Note 1 to entry: Also known as a “stop bushing.”
3.65
technical specification
requirements that shall be fulfilled by the equipment to comply with the functional specification
3.66
test pressure
pressure at which the equipment is tested based upon all relevant design criteria
3.67
test temperature
temperature at which the equipment is tested based upon all relevant design criteria
3.68
torque anchor
device that prevents the stator and/or tubing from backing off due to rotational torque generated by the
interference fit between the rotor and the stator
3.69
tubing
pipe placed within a well to serve as a production or injection conduit
3.70
tubing deployed
PCP system for which the stator is run into the well on the bottom of the tubing string
3.71
type
equipment with unique characteristics that differentiate it from other functionally similar equipment
3.72
unique identifier
unique combination of alphanumeric characters to identify a specific component

ISO/DIS 15136-1:2025(en)
3.73
validated capacity per rpm
volumetric capability determined through design validation testing
Note 1 to entry: “rpm” has been retained in this term on the basis that it is part of an established industry terminology.
However, it is deprecated by ISO as a unit, in which case it is rendered as the accepted form “r/min.”
3.74
wellhead
composite of equipment used at the surface to maintain control of the well
Note 1 to entry: Included in the wellhead equipment are casing heads (lowermost and intermediate), tubing heads,
Christmas tree equipment with valves and fittings, casing and tubing hangers, and associated equipment.
4 Abbreviated terms and symbols
4.1 For the purposes of this part of ISO 15136, the following abbreviated terms apply.
BHT bottomhole temperature
C30 hydrocarbon fractions with more than 30 carbon atoms per molecule
+
CP failure in the cover cement-prime cement (interfacial failure) day (unit of time)
d day (unit of time)
GOR gas oil ratio
M failure in the prime cement-metal interface (interfacial failure) measured depth
MD measured depth
NDE non-destructive examination
NPSH net positive suction head
PCP progressing cavity pump
PIP pump intake pressure
R failure of the rubber (substrate failure)
RC failure in the rubber-cover cement (interfacial failure)
rpm revolutions per minute
TVD true vertical depth
4.2 For the purposes of this part of ISO 15136, the following symbols are
...