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We are having plan to do heater online cleaning on one of our cylindrical type heater...our problem are that we have only 3 small observation hole that really not enough to do the online cleaning. We have idea to open the accessing door (man way) at the bottom of the heater and do the online cleaning through this way. Is there any person here that ever open their manway while heater is in operation?I think it is still save enough because the draft inside the heater is negative so there will be no fire will go out through that way.
 
Answers
12/12/2012 A: Ricardo Correia, Portugal, jrmc1977@gmail.com
We enlarge the doors in the convection sector, and radiation they can execute the procedure in more than 50% of radiation.
We remove the heaters to repair, but meanwhile we close with a manway. To clean I think you shouldn't do that.
20/06/2012 A: Mike Watson, Tube Tech International Ltd, mike.watson@tubetech.com
Online cleaning is not all it seems, unless you can answer te question "How Clean is Clean?" Tube Tech International use all On-Line and Off-Line systems. Fact: On-Line cleaning will only take the least path of resistance and achieves in reality about 5 to 25% surface contact. It does NOT "Clean" all surfaces and only cleans those areas where resistance is low.
The 3 small observation holes are indeed not enough to clean online (Nor are the others!). The tubes sadly remain "Inaccessibility". Tube Tech have opened man ways at both top, middle and bottom of heaters during operation without danger however it serves little purpose to aid cleaning.
Your companies objective is to remove teh tube foulant to improve heat transfer co-efficiency i.e. "Clean" IT!. The only way you will do this is to utilise the new "Off-Line" robotic system which by comparison will provide 95% cleanliness as opposed to 5%.