Spirax Sarco Steam Jet Thermocompressor, Инструкция по установке и обслуживанию

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IM-P493-01 EMM Issue 2 8
3.2 Motive steam piping - Installation considerations:
3.2.1 The steam supply line to the thermocompressor is to be insulated to minimise heat
loss and for personnel protection.
3.2.2 A steam isolation valve should be provided in the steam line, feeding the SJT steam jet
thermocompressor. This should be installed in a vertical run of piping, in accordance
with recommended good practice for steam lines.
3.2.3 The thermocompressor should be located as close as possible to the vessel where
the vacuum is required, thus keeping the piping as short and as straight as possible.
The number of flanged joints should also be kept to a minimum as they are a potential
source of leaks and add to the resistance of the piping.
3.2.4 Spirax-Sarco Limited strongly recommend the incorporation of a steam strainer. This
should be positioned upstream of any valve feeding the thermocompressor.
3.2.5 The steam piping to the thermocompressor should come off the top of the main line,
since that is the region of driest steam within the line.
3.3 Discharge piping - Installation considerations:
3.3.1 Long runs of pipework in which the flow is vertically upwards must be avoided.
3.3.2 Discharge piping should be kept as short and as straight as possible with the minimum
number of bends and fittings.
3.3.3 We strongly recommend that the Installation Engineer performs his own velocity
calculations to size the pipework, rather than simply relying on the discharge connection
size as being a reliable basis.
3.3.4
When the proposed installation is to have the thermocompressor discharging directly
to the atmosphere, we recommend that a silencer is fitted to bring the noise down to
an acceptable level.
3.3.5 The discharge piping must be free of any loops in the vertical plane. These are potential sources
of liquid and solids collection points and they can cause operational problems - particularly if
the suction gas contains droplets, dust or a vapour near its saturation point.
3.4 General recommendations - Installation considerations:
3.4.1 All connecting pipework must be sized and installed with good working practice.
We strongly recommend that the Installation Engineer performs his own velocity
calculations to size all pipework and does not simply make the piping the same size
as the corresponding connections at the termination points of the thermocompressor,
without first performing this check.
3.4.2 All termination points of the Thermocompressor are not designed to be load bearing,
therefore the customer is responsible for ensuring that all connecting pipes are free of
stresses. We recommend that heavy pipes are supported from adjacent steelwork, to
prevent loads being transmitted to the thermocompressor.
3.4.3 Gaskets, valves, cocks and any in-line instruments should not reduce the cross sectional
area of the pipes. This is of particular importance in the suction and discharge piping.
3.4.4
Ensure that low points of all interconnecting pipework have suitable connections for
drains.
3.4.5 We strongly recommend that all lines connected to the thermocompressor incorporate
connections for pressure tappings. Thus, should an operational problem arise, gauges
can be quickly fitted, which will then help to identify a particular problem.