ISO 10976:2015 冷蔵軽質炭化水素液—LNG船に搭載された貨物の測定 | ページ 6

3.1.1

absolute pressure

total of the gauge pressure plus the pressure of the surrounding atmosphere

3.1.2

aerating

<context of preparing a tank for entry> introduction of fresh air with an acceptable dew point into the tank to purge inert gases and to increase the oxygen content to approximately 21 % of volume so as to ensure a breathable atmosphere

3.1.3

approved equipment

equipment of a design approved by a recognized authority, such as a governmental agency, classification society or other accredited agency which certifies the particular equipment as safe for use in a specified hazardous atmosphere

3.1.4

automatic tank gauge

ATG

instrument that automatically measures and displays liquid levels or ullages in one or more tanks, either continuously, periodically or on demand

3.1.5

automatic tank thermometer

ATT

instrument that automatically measures and displays the temperature of the contents in a tank, continuously, periodically or on demand

3.1.6

boil off

process of evaporation of a liquid resulting from heat ingress or a drop in pressure

3.1.7

boil-off gas

vapour produced by boil off

3.1.8

cool down

process of reducing the temperature of equipment, such as piping, transfer arms and tanks associated with custody transfer cargo movements, to required operating temperatures

3.1.9

constant pressure/floating piston sample container

CP/FP sample container

sample container, usually used for intermittent sampling, capable of maintaining constant pressure during the sampling of gas from the process line into the gas cylinder

[SOURCE:ISO 8943:2007, 3.4, modified]

3.1.10

continuous sampling

sampling from gasified LNG with constant flow rate

[SOURCE:ISO 8943:2007, 3.5]

3.1.11

drying

process of reducing the moisture in the ship tank by displacement or dilution with an inert gas or by the use of a drying system

3.1.12

filling limit

filling ratio

quantity to which a tank may be safely filled, taking into account the possible expansion (and change in density) of the liquid

Note 1 to entry: Filling limit (i.e. volume) and filling ratio are expressed as a percentage of the total capacity of a tank.

3.1.13

gas codes

regulations on the construction of ships carrying liquefied gases developed by the International Maritime Organization

Note 1 to entry: These include the IMO International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) (generally applies to ships built after 17 July 1986), the IMO Code for Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (GC Code) (generally applies to ships built on or after 31 December 1976 but prior to 17 July 1986) and the IMO Code for Existing Ships Carrying Liquefied Gases in Bulk (generally applies to ships delivered before 31 December 1976), as applicable to each vessel.

3.1.14

gas sample container

sample container, usually used for continuous sampling and used for the retention of the gas sample and for its transfer to an analysing instrument

[SOURCE:ISO 8943:2007, 3.6]

3.1.15

gassing up

process of replacing an inert atmosphere in a cargo tank with the vapour from shore or from another cargo tank to a suitable level to allow cooling down and subsequent loading to achieve a specified environment with at least a defined methane (CH₄), carbon dioxide (CO₂) and oxygen (O₂) content

3.1.16

heel

amount of cargo retained in a cargo tank prior to loading or after discharge

3.1.17

inerting

introduction of inert gas into a tank with the object of attaining the inert condition

3.1.18

intermittent sampling

sampling from gasified LNG with predetermined intervals or with predetermined flow amount intervals

[SOURCE:ISO 8943:2007, 3.9]

3.1.19

letter of protest

letter issued by any participant in a custody transfer citing any condition with which issue is taken and which serves as a written record that a particular action or finding was observed/questioned at the time of occurrence

3.1.20

LNG carrier

cargo ship specifically constructed and used for the carriage of LNG in bulk

3.1.21

LNG sample vaporizer

apparatus to completely gasify the LNG sample collected from the LNG transfer line

[SOURCE:ISO 8943:2007, 3.11]

3.1.22

multiple-spot ATT

multiple-point ATT

ATT consisting of multiple spot temperature element sensors to measure the temperature(s) at selected liquid level(s)

[SOURCE:ISO 4266‑5:2002, 3.4, modified]

Note 1 to entry: The readout equipment for a multiple-point averaging ATT averages the readings from the submerged temperature elements sensors to compute the average temperature of the liquid in the tank, and can also display the temperature profile in the tank.

3.1.23

notice of apparent discrepancy

notice issued by any participant in a custody transfer citing any discrepancy in cargo quantities and which serves as a written record that such a discrepancy was found

3.1.24

offline analysis

procedure of analysis implemented on the representative sample gas that is once charged into a gas sample container or a CP/FP sample container

[SOURCE:ISO 8943:2007, 3.13]

3.1.25

online analysis

procedure of analysis implemented using analytical equipment that is directly connected through pipelines or other means to the sampling device

[SOURCE:ISO 8943:2007, 3.14, modified]

3.1.26

online gas chromatograph

gas chromatograph that is directly connected to the pipelines or sampling device to implement online analysis

[SOURCE:ISO 8943:2007, 3.15]

3.1.27

seal water

water used in the water seal type gas sample holder to preclude contact of the gas sample with the atmosphere

[SOURCE:ISO 8943:2007, 3.19]

3.1.28

tank capacity table

numeric tables that relate the liquid level in a tank to the volume contained in that tank

3.1.29

vapour

fluid in the gaseous state that is transferred to/from or contained within the cargo tank

3.1.30

vapour pressure

pressure at which a liquid and its vapour are in equilibrium at a given temperature

3.1.31

verification

process of confirming the accuracy of an instrument by comparing to a source with known accuracy

3.1.32

warming up

process of warming the cargo tanks from cargo carriage temperature to required temperature

3.1.33

waterless-type gas sample holder

holder without seal water (typically using an expandable/contractible, transformable rubber membrane) and used for collecting gasified LNG

[SOURCE:ISO 8943:2007, 3.22]

3.1.34

water-seal-type gas sample holder

holder with seal water used for collecting gasified LNG

[SOURCE:ISO 8943:2007, 3.23]