{"id":4642,"date":"2017-12-15T10:42:56","date_gmt":"2017-12-15T09:42:56","guid":{"rendered":"http:\/\/www.checkstar-techblog.it\/?p=4642"},"modified":"2022-11-11T14:46:07","modified_gmt":"2022-11-11T13:46:07","slug":"abatement-gas-diesel-engines-the-dpf","status":"publish","type":"post","link":"https:\/\/www.checkstar-techblog.it\/en\/abatement-gas-diesel-engines-the-dpf\/","title":{"rendered":"Abatement of particulate pollutant emissions - Diesel engines - The DPF"},"content":{"rendered":"

Continuing with 'technical pills' that can be useful to you in your daily work, in the next few posts we will address a very topical subject, namely exhaust gas abatement and treatment devices.<\/p>\n

As we have written, after describing the philosophy, we will publish solved real cases that can serve as examples and help to better understand how to deal with possible future cases.<\/p>\n

DPF (Diesel Particulate Filter)
\n<\/strong>
\nLet's start with the DPF: this is a device used on diesel engines to reduce nitrogen oxide (NOx) emissions into the environment.<\/p>\n

\"\"<\/p>\n

This device, mounted at the beginning of the car's exhaust pipes, is controlled directly by the engine control unit, which monitors its operation and ensures proper maintenance.<\/p>\n

The DPF is combined with a pre-catalyser, the purpose of which is to physically filter out PM10 particulate matter.<\/p>\n

The system collects the flue gases in the exhaust manifold and then conveys them to the catalytic converter, through the filter proper, then to the expansion tank and then through the silencer, before exiting.<\/p>\n

\"\"<\/p>\n

Since the DPF is physically a filter, by its very nature it gets clogged over time. This is why some are designed with a 'disposable' philosophy and therefore need to be replaced regularly when completely clogged.<\/p>\n

Most, however, are designed to 'regenerate', an action that the engine control unit puts into action when the clogging threshold reaches a pre-set level.<\/p>\n

Normally below 60 km\/h (i.e. during urban cycles) the system filters gases and traps dust; above 70 km\/h (i.e. during a normal extra-urban journey) the system sets itself up for 'regeneration'. During this process, it is the job of the engine control unit to diagnose the system to detect the degree of clogging and, if necessary, initiate cleaning: this is carried out by means of post-injections of fuel in order to raise the temperature and thus burn off the collected dust. For the driver, this is not detected, except for the engine idle speed, which remains accelerated around 1000 rpm.<\/p>\n

If the driver of the vehicle is warned by the DPF warning light coming on and the car goes into recovery, this means that natural regeneration has failed or that the driving style \"\"of the vehicle is not facilitating the completion of regeneration. In such cases, it will be essential to go to the workshop for so-called forced regeneration or, in extreme cases, replacement of the DPF.<\/p>\n

The workshop operator knows that in these cases, before carrying out forced regeneration with the tester, it is necessary to try the operation on the road; that is, to facilitate the rise in temperature of the DPF by travelling a few dozen kilometres in lower gears so that the engine speed remains around 2000\/2500 rpm.<\/p>\n

Only if regeneration is unsuccessful after this attempt will it be possible to carry out forced regeneration and consider replacing the DPF.<\/p>\n

We will stop here for now. Until next time, where we will delve into forced regeneration with a Magneti Marelli diagnostic tester.\u00a0\u00a0<\/p>\n

\"\"<\/p>\n

 <\/p>\n

 <\/p>\n

 <\/p>","protected":false},"excerpt":{"rendered":"

As we continue to deal with 'technical pills' that may be useful to you in your daily work, in the next few posts we will address a topic of great [...]<\/p>","protected":false},"author":49,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"acf":[],"featured_image_urls":{},"appp_media":null,"views":1413,"_links":{"self":[{"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/posts\/4642"}],"collection":[{"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/users\/49"}],"replies":[{"embeddable":true,"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/comments?post=4642"}],"version-history":[{"count":0,"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/posts\/4642\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/media?parent=4642"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/categories?post=4642"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.checkstar-techblog.it\/en\/wp-json\/wp\/v2\/tags?post=4642"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}