Page 31 - igem-g-4 edition 2

IGEM/G/4 Edition 2
meter installation outlet valve (MIOV)
Valve fitted downstream of all the other components of a meter installation to shut off the
supply of gas from a meter installation.

meter outlet adaptor
Fitting which facilitates the connection of a gas consumer’s installation pipework to the outlet
of a meter.

meter outlet valve (MOV)
Valve fitted downstream of, and adjacent to, a gas meter to shut off the supply of gas from
the meter.

meter owner
Person owning a meter and/or a meter installation (see also “legacy meter owner”).

meter pulse significance (scaling factor)
Number of units of volume represented by each contact closure in a low frequency (LF)
transmitter or a high frequency (HF) transmitter.

meter regulator
Device located in close proximity to a primary meter which is solely to control the pressure of
the gas within the measurement device and/or installation pipework and is not separated from
the measurement device by buried pipework, except short lengths specifically included in the
installation design for access purposes.

meter spool
“Pipe section” body of an ultrasonic meter (USM) to which the transducer mountings are
attached.

meter tube
Primary metering device, together with the requisite upstream and downstream straight
lengths of pipe and including any flow conditioning device.

microtunnelling
Use of small diameter tunnelling machines to install underground pipes by remote control from
the surface using pipe-jacking techniques.

midi-rig
Steerable surface-launched drilling equipment for the installation of pipes, conduits and
cables. Applied to intermediate-sized drilling rigs used as either a small directional drilling
machine or a large guided boring machine.

mini-horizontal directional drilling (MINI-HDD)
Term sometimes applied to guided boring.

minimum allowable suction
For each stage, the lowest pressure (measured at the inlet flange of the cylinder) below which
the combined rod loading or gas suction loading or gas loading or discharge temperature or
crankshaft torque loading (whichever is governing) will exceed the maximum allowable during
operation at the setpoint pressure of the discharge relief valve and other specified gas
conditions for the stage.

minimum source pressure
Pressure available at the source at the time of the system design flow rate.

mismatch
Dimensional irregularity of two pipes to be jointed.

mobile dwelling
Caravan holiday home, a residential park home or a permanently moored boat.

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