ISO 21225-1:2018 地下パイプラインネットワークのトレンチレス交換用のプラスチック配管システム—パート1：パイプ破裂とパイプ抽出によるライン上の交換 | ページ 6

3.1.1

CCTV system

system comprised of cameras, recorders, interconnections and displays that are used to inspect pipelines

3.1.2

characteristic

property, dimension or other feature of a material or component

3.1.3

coated pipe

pipe with a peelable, contiguous thermoplastic additional layer on the outside of the pipe

3.1.4

installed pipe

replacement pipe after installation

3.1.5

maintenance

routine work undertaken to ensure the continuing performance of an asset

3.1.6

pipe with co-extruded layers

pipe with smooth internal and external surface, having co-extruded layers on either or both the outside and inside of the pipe ここで, all layers have the same MRS rating

3.1.7

pipeline system

interconnecting pipe network for the conveyance of fluids

3.1.8

rehabilitation

measures for restoring or upgrading the performance of existing pipeline systems, including renovation, repair and replacement

3.1.9

renovation

work incorporating all or part of the original fabric of the pipeline, by means of which its current performance is improved

3.1.10

repair

rectification of local damage

3.1.11

replacement

construction of a new pipeline, on or off the line of an existing pipeline ここで, the function of the new pipeline system incorporates that of the old

3.1.12

replacement pipe

new pipe installed for rehabilitation purposes

3.1.13

replacement system

replacement pipe and all relevant fittings for trenchless replacement on or off an existing pipeline for the purposes of rehabilitation

3.1.14

solid wall single layered pipe

pipe with smooth internal and external surface, extruded from the same compound/formulation throughout the wall

3.1.15

system test pressure

STP

pressure applied to the installed pipeline system in order to ensure its integrity and leaktightness

3.1.16

technique family

group of renovation or trenchless replacement techniques which are considered to have common characteristics for standardization purposes

3.1.17

trenchless replacement

replacement without opening trenches other than small excavations to provide access for the particular technique

3.2.1

bursting head

tool that can crack or split the existing pipe material

Note 1 to entry: Brittle pipe materials such as clay or grey cast iron crack. Ductile pipe materials such as ductile iron, steel or PVC-U split.

3.2.2

pipe bursting

on the line replacement method in which an existing pipe is broken by longitudinal splitting or brittle fracture, using a mechanically applied force from within ここで, the pipe fragments are forced into the surrounding ground and a new pipe of the same, smaller or larger diameter, is simultaneously pulled in

3.2.3

pipe extraction

on the line replacement method in which an existing pipeline is extracted by pulling or pushing and replaced with a new pipe of the same, smaller or larger diameter, is simultaneously pulled or pushed in

Figure 2 — Technique families for trenchless replacement of underground pipeline networks using plastics pipes, within the scope of pipeline rehabilitation techniques

a	This document is applicable.
b	In scope of ISO 21225-2.
c	Outside scope of ISO 21225, see ISO 11295 [1].

3.3.1

minimum bending radius

minimum radius at any point throughout the length of the pipeline, measured to the longitudinal axis of the pipe

Note 1 to entry: This is usually expressed as a multiple of the pipe diameter.

3.3.2

minimum mean outside diameter

d_em,min

minimum value of the mean outside diameter as specified for a given nominal size

[SOURCE:ISO 4427‑1:2007, 3.1.1.6]

3.3.3

minimum wall thickness at any point

e_min

minimum value of the wall thickness at any point around the circumference of a component as specified

[SOURCE:ISO 4427‑1:2007, 3.1.1.11]

3.3.4

nominal outside diameter

d_n

specified outside diameter, in millimetres, assigned to a nominal size DN/OD

Note 1 to entry: For thermoplastics solid-wall components, the value of nominal outside diameter is identical to the minimum mean outside diameter, d_em,min.

[SOURCE:ISO 4427‑1:2007, 3.1.1.3, modified by addition of Note 1 to entry.]

3.3.5

nominal thickness of the coating

e_coating

arithmetic mean of a number of measurements of the coating thickness around the circumference and in the same cross-section of a component

3.3.6

nominal wall thickness

e_n

numerical designation of the wall thickness of a component, which is a convenient round number, approximately equal to the manufacturing dimension in millimetres

Note 1 to entry: For thermoplastics solid-wall components, the value of nominal wall thickness, e_n, is identical to the specified minimum wall thickness at any point, e_min.

[SOURCE:ISO 4427‑1:2007, 3.1.1.9, modified by addition of Note 1 to entry.]

3.3.7

out-of-roundness

difference between the measured maximum and the measured minimum outside diameter in the same cross-sectional plane of the pipe

3.3.8

standard dimension ratio

SDR

ratio of the nominal outside diameter, d_n, to its nominal wall thickness, e_n

3.3.9

wall thickness

e

value of the measurement of the wall thickness at any point around the circumference of a component

3.4.1

compound/formulation

clearly defined homogenous mixture of base polymer with additives, e.g. anti-oxidants, pigments, stabilisers and others, at a dosage level necessary for the processing and intended use of the final product

3.4.2

lower confidence limit of the predicted hydrostatic strength

σ_LPL

quantity, with the dimensions of stress, which represents the 97,5 % lower confidence limit of the predicted hydrostatic strength at a temperature θ and time t

Note 1 to entry: It is expressed in megapascals.

3.4.3

melt mass-flow rate

MFR

value relating to the viscosity of the molten material at a specified temperature and load

Note 1 to entry: It is expressed in grams per 10 min (g/10 min).

3.4.4

minimum required strength

MRS

value of σ_LPL rounded down to the next smaller value of the R10 series or R20 series, depending on the value of σ_LPL

Note 1 to entry: R10 and R20 series are the Renard number series according to ISO 3 and ISO 497.

3.4.5

oxidation induction time

OIT

relative measure of a stabilized material’s resistance to oxidative decomposition, determined by the calorimetric measurement of the time interval to the onset of exothermic oxidation of the material at a specified temperature in an oxygen or air atmosphere, under atmospheric pressure

3.5.1

butt fusion joint

joint made by heating the planed ends of matching surfaces by holding them against a flat heating plate until the PE material reaches fusion temperature, quickly removing the heating plate and pushing the two softened ends against one another

3.5.2

electrofusion joint

joint between a PE socket or saddle electrofusion fitting and a pipe or fitting with spigotted ends, made by heating the electrofusion fittings by the Joule effect of the heating element incorporated at their jointing surfaces, causing the material adjacent to them to melt and pipe and fitting surfaces to fuse

Note 1 to entry: A support sleeve inserted into the pipe bore can be used to provide a permanent support for the PE pipe to prevent creep in the pipe wall under radial compressive forces.