Some common reasons for filters choking are as follows;
1. Corrosion particles which might come with the feed, from upstream units when sudden or uneven fluctuation in flow is observed.
2. The cold feed from the storage tank, especially when the level of the tank is very low.
3.The low temperature of the feed.
4. Cracked feedstock with a high percentage of particles from vacuum unit.
5. Poor cleaning methods of filter cartridges.
6. Damage filter cartridges
7. Heavy crude oil which might contain heavy particles at the end passing to downstream units