{"id":729,"date":"2015-10-26T15:30:39","date_gmt":"2015-10-26T15:30:39","guid":{"rendered":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/?p=729"},"modified":"2015-10-26T15:30:39","modified_gmt":"2015-10-26T15:30:39","slug":"air-compressors-air-treatment-and-pressure-regulationair-receivers-and-compressor-control","status":"publish","type":"post","link":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/air-compressors-air-treatment-and-pressure-regulationair-receivers-and-compressor-control\/","title":{"rendered":"Air Compressors, Air Treatment and Pressure Regulation:air receivers and compressor control"},"content":{"rendered":"<div class=\"kvthc6a0dae00ee4b0\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '61e5902552e2353963d8d2f1bd1f4a8f',\n\t\t'format' : 'iframe',\n\t\t'height' : 250,\n\t\t'width' : 300,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/61e5902552e2353963d8d2f1bd1f4a8f\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.kvthc6a0dae00ee4b0 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.kvthc6a0dae00ee4b0 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.kvthc6a0dae00ee4b0 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.kvthc6a0dae00ee4b0 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.kvthc6a0dae00ee4b0 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<h4 align=\"justify\"><font size=\"5\"><font style=\"font-weight: bold\">air receivers and compressor control<\/font><\/font><\/h4>\n<p align=\"justify\"><font size=\"5\">An air receiver is used to store high-pressure air from the compressor. Its volume reduces pressure fluctuations arising from changes in load and from compressor switching.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">Air coming from the compressor will be warm (if not actually hot!) and the large surface area of the receiver dissipates this heat to the surrounding atmosphere. Any moisture left in the air from the compressor will condense out in the receiver, so outgoing air should be taken from the receiver top.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">Figure 3.13 shows essential features of a receiver. They are usually of cylin- drical construction for strength, and have a safety relief valve to guard against high pressures arising from failure of the pressure control scheme. Pressure indi- cation and, usually, temperature indication are provided, with pressure switches for control of pressure and high-temperature switches for remote alarms.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">A drain cock allows removal of condensed water, and access via a manhole allows cleaning. Obviously, removal of a manhole cover is hazardous with a pressurized receiver, and safety routines must be defined and followed to pre- vent accidents.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">Control of the compressor is necessary to maintain pressure in the receiver. The simplest method of achieving this is to start the compressor when receiver pressure falls to some minimum pressure, and stop the compressor when pres- sure rises to a satisfactory level again, as illustrated in Figure 3.14. In theory two pressure switches are required (with the motor start pressure lower than the mo- tor stop pressure) but, in practice, internal hysteresis in a typical switch allows one pressure switch to be used. The pressure in the receiver cycles between the start and stop pressure settings.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\"><a href=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0073.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"Air Compressors, Air Treatment and Pressure Regulation-0073\" border=\"0\" alt=\"Air Compressors, Air Treatment and Pressure Regulation-0073\" src=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0073_thumb.jpg\" width=\"372\" height=\"199\"><\/a><\/font> <\/p>\n<p align=\"justify\"><font size=\"5\"><a href=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0074.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"Air Compressors, Air Treatment and Pressure Regulation-0074\" border=\"0\" alt=\"Air Compressors, Air Treatment and Pressure Regulation-0074\" src=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0074_thumb.jpg\" width=\"378\" height=\"204\"><\/a><\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">In Figure 3.15 another method of pressure control is shown, where the compres- sor runs continuously and an exhaust valve is fitted to the compressor outlet. This valve opens when the required pressure is reached. A non-return valve prevents air returning from the receiver. This technique is known as exhaust regulation.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">Compressors can also be controlled on the inlet side. In the example of Figure 3.16, an inlet valve is held open to allow the compressor to operate, and is closed when the air receiver has reached the desired pressure (the compressor then forms a near vacuum on its inlet side).<\/font> <\/p><div class=\"ilzpk6a0dae00ee6fc\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '0c1eb4c533eaedb7b996f49a5a4983a9',\n\t\t'format' : 'iframe',\n\t\t'height' : 300,\n\t\t'width' : 160,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/0c1eb4c533eaedb7b996f49a5a4983a9\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.ilzpk6a0dae00ee6fc {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.ilzpk6a0dae00ee6fc {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.ilzpk6a0dae00ee6fc {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.ilzpk6a0dae00ee6fc {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.ilzpk6a0dae00ee6fc {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<div class=\"yscwj6a0dae00ee5c6\" ><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-0778475562755157\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- 300x600 hydraulics-and-pneumatics -->\n<ins class=\"adsbygoogle\"\n     style=\"display:inline-block;width:300px;height:600px\"\n     data-ad-client=\"ca-pub-0778475562755157\"\n     data-ad-slot=\"3735577695\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.yscwj6a0dae00ee5c6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.yscwj6a0dae00ee5c6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.yscwj6a0dae00ee5c6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.yscwj6a0dae00ee5c6 {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.yscwj6a0dae00ee5c6 {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n\n<p align=\"justify\"><font size=\"5\">The valves in Figures 3.15 and 3.16 can be electrically operated solenoid valves controlled by pressure switches, or can be pneumatic valves controlled directly by receiver pressure.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">The control method is largely determined by flow rates from receiver to the load(s) and the capacity of the compressor. If the compressor has significant spare capacity, for example, start\/stop control is commonly used.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">If compressor capacity and load requirements are closely matched, on the other hand, short start\/stop cycling may cause premature wear in the electrical starter for the compressor motor. In this situation, exhaust or inlet regulation is preferred.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">Air receiver size is determined by load requirements, compressor capacity, and allowable pressure deviations in the receiver. With the compressor stopped, Boyle\u2019s law (expression 1.17) gives the pressure decay for a given volume of air delivered from a given receiver at a known pressure. For example, if a receiver of 10 cubic meters volume and a working pressure of 8 bar delivers 25 cubic meters of air (at STP) to a load, pressure in the receiver falls to approximately 5.5 bar.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\"><a href=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0075.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"Air Compressors, Air Treatment and Pressure Regulation-0075\" border=\"0\" alt=\"Air Compressors, Air Treatment and Pressure Regulation-0075\" src=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0075_thumb.jpg\" width=\"338\" height=\"142\"><\/a><a href=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0076.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"Air Compressors, Air Treatment and Pressure Regulation-0076\" border=\"0\" alt=\"Air Compressors, Air Treatment and Pressure Regulation-0076\" src=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-content\/uploads\/2015\/10\/Air-Compressors-Air-Treatment-and-Pressure-Regulation-0076_thumb.jpg\" width=\"341\" height=\"132\"><\/a><\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">With the compressor started, air pressure rises at a rate again given by expression 1.17 (with the air mass in the receiver being <i>increased <\/i>by the difference between the air delivered by the compressor and that removed by the load).<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">These two calculations give the cycle time of the compressor when com- bined with settings of the cut-in and drop-out pressure switches. If this is unac- ceptably rapid, say less than a few minutes, then a larger receiver is required. Manufacturers of pneumatic equipment provide nomographs which simplify these calculations.<\/font> <\/p>\n<p align=\"justify\"><font size=\"5\">An air receiver is a pressure vessel and as such requires regular visual and volumetric pressure tests. Records should be kept of the tests.<\/font><\/p>\n","protected":false},"excerpt":{"rendered":"<p>air receivers and compressor control An air receiver is used to store high-pressure air from the compressor. Its volume reduces pressure fluctuations arising from changes in load and from compressor switching. Air coming from the compressor will be warm (if not actually hot!) and the large surface area of the receiver dissipates this heat to [&hellip;]<br \/><a href=\"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/air-compressors-air-treatment-and-pressure-regulationair-receivers-and-compressor-control\/\" class=\"more-link\" >Continue reading&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/posts\/729"}],"collection":[{"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/comments?post=729"}],"version-history":[{"count":1,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/posts\/729\/revisions"}],"predecessor-version":[{"id":730,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/posts\/729\/revisions\/730"}],"wp:attachment":[{"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/media?parent=729"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/categories?post=729"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/hydraulics-and-pneumatics\/wp-json\/wp\/v2\/tags?post=729"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}