<table cellspacing="0" cellpadding="0" border="0"><tr><td valign="top">Very informative Alan, thank you.<br/><br/>I'm going to assume that the "in front of suction" is meant that placement is upstream of the pump.<br/><br/>The HP volumes are particularly interesting.<br/><br/>Joe<a href="http://overview.mail.yahoo.com?.src=iOS"><br/><br/>Sent from Yahoo Mail for iPad</a></td></tr></table> <div id="_origMsg_">
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<span style="font-weight:bold">From:</span>
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Alan James <alanlindsayjames@yahoo.com>; <br>
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<span style="font-weight:bold">To:</span>
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psubs.org <personal_submersibles@psubs.org>; <br>
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<span style="font-weight:bold">Subject:</span>
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[PSUBS-MAILIST] G.L. Rules Piping systems, Pumps & Compressors <br>
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<span style="font-weight:bold">Sent:</span>
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Wed, Jan 15, 2014 10:09:47 PM <br>
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<td valign="top"><div style="color:#000;background-color:#fff;font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:14pt;"><div id="yiv9824518087"><div><div style="color:rgb(0, 0, 0);background-color:rgb(255, 255, 255);font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;font-size:14pt;"><div id="yiv9824518087"><div id="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4991"><div style="color:rgb(0, 0, 0);background-color:rgb(255, 255, 255);font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;font-size:14pt;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4959" id="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4990"><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">Hi people,</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">I have omitted the summary on Vessels & Apparatus
Under Pressure</div><div
id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">as there wasn't much of consequence that hadn't previously been covered,</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">and are now on to Piping Systems, Pumps & Compressors.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">Some good stuff here.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> Pipes which go through the pressure
hull are to be fitted with two shut off</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">devices. One of which is located at the hull wall.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> Pipes passing through spaces inadequate for maintenance are to be one piece.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> Manual
shut off devices are to be closed by turning in the clockwise direction.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> All sea valves & essential shut off valves are to be clearly indicated.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> Each hose is to be designed for the burst pressure, which is for liquids, 4x &</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">for gases, 5x the maximum allowable working pressure.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> Generally submersibles are to be equipped with a bilge system capable of </div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542">removing water from condensation or leakage from all spaces in the sub.</div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"> In the bilge system, two non return valves are required. The wording for their placement
is <span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_4450">"two non return valves are to be mounted in front of the freeing connections. One </span><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_4451">of these non-return valves is to be placed in the pipe in front </span><span style="font-size:14pt;background-color:transparent;">of each suction." (not sure what they mean).</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4964"><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_50">
Bilge pumps are to be of self priming type.</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4966"><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_54"> If you are using the bilge pump to also operate your trimming & compensating</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4968"><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_58">systems, valves have to
be fitted so that from the event of wrongly
operating valves</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_62">or partially opened valves, no seawater can get in the submersible. T</span><span style="font-size:14pt;background-color:transparent;" id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_5541">he bilge system has to have </span><span id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_5545" style="background-color:transparent;font-size:14pt;">a back up pump, & with</span><span id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_5540" style="background-color:transparent;font-size:14pt;"> an interconnected bilge / trim / compensating
system;</span><span id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_5539" style="background-color:transparent;font-size:14pt;"> the back up pump must </span><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_87">be able
to </span><span style="background-color:transparent;font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_5868">service all systems.</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="background-color:transparent;font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_8_1389755570110_14">Where diving tanks are emptied by pumps, the back up pump has to be connected to the </span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;"
class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="background-color:transparent;font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_8_1389755570110_18">emergency power supply.</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="background-color:transparent;font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_8_1389755570110_22">The air supply for the diving ballast tanks has to be sufficient to blow the tanks 4x at the surface & 1.5x at the nominated diving depth. And enough to blow the compensating tanks</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica,
Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="background-color:transparent;font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_8_1389755570110_26">3 times completely at nominated diving depth. (I'm not sure if this is additional to the ballast tank requirements)</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970 yui_3_13_0_ym1_1_1389822418081_2416"><span style="background-color:transparent;font-size:14pt;">The compressed air supply is to be carried in two separate banks of receivers with the same total volume & fitted with valves so that no unintentional pressure equalization can
occur between different systems.</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970 yui_3_13_0_ym1_1_1389822418081_2416"><span style="background-color:transparent;font-size:14pt;">Where pressure reducing valves are fitted these are to be redundant. In single cases provision can be made for bypassing with manual control. In addition, a safety valve is to be fitted on the low pressure side of the pressure reducing valve, or equally safe alternative.</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;"
class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970 yui_3_13_0_ym1_1_1389822418081_2416"><span style="background-color:transparent;font-size:14pt;">Alan</span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970 yui_3_13_0_ym1_1_1389822418081_2416"><span style="background-color:transparent;font-size:14pt;"><br></span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4970"><span style="background-color:transparent;font-size:14pt;"
id="yiv9824518087yui_3_13_0_ym1_8_1389755570110_30"><br></span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542" style="color:rgb(0, 0, 0);font-size:14pt;font-family:HelveticaNeue, 'Helvetica Neue', Helvetica, Arial, 'Lucida Grande', sans-serif;background-color:transparent;font-style:normal;" class="yiv9824518087yui_3_13_0_ym1_1_1389755570110_4978"><span style="font-size:14pt;" id="yiv9824518087yui_3_13_0_ym1_7_1389404803015_70"><br></span></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"><br></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"><br></div><div id="yiv9824518087yui_3_13_0_ym1_1_1389404803015_2542"><br></div></div></div></div></div></div></div></div></td>
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