InstrEng Instrumentation Engineering

<div dir="ltr" style="text-align: left;" trbidi="on">
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">An important factor in selecting the correct Safety Relief Valve is choosing the correct materials for the application. It is obviously impossible to cover all possible applications, but we will provide some general guidelines here.</span><br />
<br style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;" />
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;"><b>Sour gas applications:</b> Here, NACE recommendations should be followed. Most wrought grades are acceptable to NACE. Therefore, in general, duplex valves with bar stock nozzles and discs will meet NACE requirements. Some limited cast grades will generally comply also:</span><br />
<ul style="text-align: left;">
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASTM A890 CE3MN UNS J93404</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 351 CD3MWCuN UNS J93380</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 351 CE8MN UNS J93380</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Z 6 CNDU 28.08 M, NF A 320-55 at 17 HRC MAX</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASTM A351 CK3MCUN (6Mo)</span></li>
</ul>
<div>
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">High -temperature applications (>530°C): As a general rule, a bellows should be used so that the spring gets protected from heat and does not shift its characteristics during eventual temperature cycles.</span></div>
<div>
<br /></div>
<div>
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">For body, bonnet and cap, up to 815 ° C cast materials can still safely be used : ASME SA 351 CF8M with a minimum 0.04% carbon content and maximum 8% ferrite content. In any case, full-rated and integral castings are recommended. Alternatives are:</span><br />
<ul style="text-align: left;">
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 351 CF8 SAME (with same chemical restrictions as CF8M)</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 217 WC6 (up to maximum 593 ° C)</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 217 WC9 (up to maximum 593 ° C)</span></li>
</ul>
<div>
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Wrought materials can also be used up to 815 ° C: ASME SA 479 Grade 316H with a carbon content between 0.04% and 10%. Alternatives are:</span><br />
<ul style="text-align: left;">
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">ASME SA 479 Grade 304H (same chemical restrictions as 316H)</span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;"> ASME SA 479 Grade 347H (same chemical restrictions as 316H)</span></li>
</ul>
</div>
<div>
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">For the temperature range 530 ° C to 815 ° C, the following precautions should also be taken into consideration:</span><br />
<ul style="text-align: left;">
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Recommended bolting material: ASME SA 193 Grade B8 Class 2/ASME SA 194 Grade 8 – strain hardened. </span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Recommended bellows material: INCONEL 625 Grade 2 (LCF) – annealed after forming or HAYNES ALLOY 230. ASTM B435 UNS N06230 is preferred above 650 ° C but is rather expensive. </span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Recommended spring material: INCONEL X750. Above 232 ° C, 316SS springs should no longer be used. INCONEL X750 or chrome-plated springs should be considered. Note that cadmium plating used in the past is no longer allowed. </span></li>
<li><span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Recommended gasket material: 316 STAINLESS STEEL.</span></li>
</ul>
<div class="separator" style="clear: both; text-align: center;">
<a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgaMZ7HiM74Tm0OyC9Wo-vyhtMidGkVl6KxS2NCwq4P6-pB8PnNzMAX7TU2S4nPGeWauAOIuAS5KxEUJRWAzAgvDig75NYIMPmmA80GUogYxDRbptwR8v0LEZxM20RhEIhBujL0IKkmS90/s1600/Spring_loaded_safety_relief.jpg" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="283" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgaMZ7HiM74Tm0OyC9Wo-vyhtMidGkVl6KxS2NCwq4P6-pB8PnNzMAX7TU2S4nPGeWauAOIuAS5KxEUJRWAzAgvDig75NYIMPmmA80GUogYxDRbptwR8v0LEZxM20RhEIhBujL0IKkmS90/s1600/Spring_loaded_safety_relief.jpg" width="320" /></a></div>
<div>
<span style="color: #545454; font-family: Open Sans, Arial, sans-serif; font-size: x-small;"><span style="line-height: 18.4888877868652px;"><br /></span></span></div>
</div>
<div>
<br style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;" />
<span style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;">Read More at: </span><a href="http://www.instreng.com/community/threads/safety-relief-valve-material-selection.914/" style="background-color: #f6f8f9; color: #666666; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px; text-decoration: none;">Safety Relief Valve Material Selection | InstrEng Forums</a></div>
</div>
<div>
<br style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;" /></div>
<br />
<br style="background-color: #f6f8f9; color: #545454; font-family: 'Open Sans', Arial, sans-serif; font-size: 13.333333969116211px; line-height: 18.488887786865234px;" />
<br /></div>

Safety Relief Valve Material Selection

An important factor in selecting the correct Safety Relief Valve is choosing the correct materials for the application. It is obviously impossible to cover all possible applications, but we will prov…

Safety Relief Valve Material Selection

Populars

InstrEng

Archive

InstrEng Instrumentation Engineering