Home › Forums › Coking › Maintenance › Pigging › Determining when to end piggings › RE: Determining when to end piggings
This a difficult item to measure on a consistancy basis. Many variables play into this equation. Coke thickness, Hot spots, Change in feed stock, different operators pigging, duration of run length. All of these can vary the pigging duration, which makes it difficult to establisk a set time for pigging with out knowing the condition of the unit until pigging begins. Even while pigging some coke may come off easy on one pass & then on the other pass(s) it may be laid down more dense ( harder firing ) causing a longer pigging duration. The more information we can get up front prior to pigging, unit upsets, firing the heater or a specific pass harder, loss of charge pump, etc, the easier it is to determine pigging durations. I am happy to continue this discussion on this form & to be able to spak with you personally.