The Diesel Particulate Filter (DPF) Explained

The Exhaust After-Treatment System of a BSVI vehicle uses a filter called the Diesel Particulate Filter (DPF). As the name suggests, the Diesel Particulate Filter's job is to trap the particulate matter from the exhaust gases. Since this trapping increases the exhaust back pressure on the engine, the filter needs to be regenerated periodically to burn off the soot accumulated in it. This is done by increasing the exhaust gas temperature and maintaining oxygen in the exhaust. thereby meeting the required PM levels, as per BSVI emission norms before they are released into the environment.

Just like any filter, DPF must also be CLEANED

To understand the working of any filter, the ‘tea strainer’ which everyone uses to pour a refreshing cup of tea is the best example! You might use the same strainer multiple times but beyond 2-3 pours, its pores get clogged and need to be cleaned thoroughly so that it can perform its function again. Similarly, any filter used in your BSVI truck needs to be regularly cleaned, regardless of what it is designed to trap so that it can continue to perform its function effectively.

Since DPF is also a filter, it has a finite capacity to store soot. And when this accumulation goes beyond a limit, it can start impeding with the flow of exhaust gases. This can lead to higher exhaust back pressure which will cause risk of unnecessary wear on your vehicle’s engine. It will also impact the emission levels. Hence, the DPF is designed to need regular maintenance and cleaning through a process called Regeneration.

Regeneration - Cleaning of the DPF

During the process of Regeneration, the soot is burned away with high temperature in the Diesel Particulate Filter (DPF). Regeneration is normally performed automatically while driving but in certain driving conditions where required temperature cannot be achieved, it has to be initiated manually.

Automatic Regeneration

Automatic regeneration happens during driving when the load on engine is high enough to reach a sufficiently high temperature. Diesel trucks covering longer distances on highways at high speeds and sufficient load and those on a heavy duty cycle, for example climbing a lot of hills, should have no problem in regenerating their DPF automatically.

When you drive continuously for several hours at low engine load or continuously run at idling speed or frequently start or stop due to traffic congestion or cover short trips in the city frequently, regeneration is not initiated automatically. It may be necessary for you to start regeneration manually in these cases.

Manual Regeneration

There’s no such thing as a good time for downtime, especially when it is unexpected. Therefore, one issue the fleet owners and their drivers should know and plan for with the coming of BSVI vehicles is Parked Regeneration or Manual Regeneration.

A warning light on the cluster will alert the driver that the filter is blocked and regeneration needs to be performed manually. Manual Regeneration can be started by parking vehicle in a hazard-free zone with all safety precautions and instructions.

More on how to initiate Manual Regeneration to follow!