You'll need to tell us more than you haven't already. ■

I'm assuming that you have some sort of separating mechanism for DRI product and screened fines, which are then diverted to something? Your subject title also refers to hot fines diverter? Now it becomes intriquing. You have a dilemma in that DRI is pyrophoric and at certain conditions will catch on fire, reoxidise, absorb moisture/water and separate to Oxygen/Hydrogen causing unsafe conditions to explosions, dust from the DRI and/or fines is combustible and under certain conditions will cuase explosive potential. Specifically, I believe you are asking if anyone has experience, under these circumstances, with a diverter gate plugging or jamming?

Firstly, as John has mentioned you need to provide far more information than what you have. Secondly, we would need to know specifically what you are experiencing, in jamming, if there are hot conditions, and the design of the gate, is it vertically installed or horizintal? We already know that it is pneumatic and DRI fines are sometimes hot, and DRI fines as well as DRI product will reoxidize and with air and other atmospheric conditions. So we can assume that jamming may be caused by DRI fines reoxidizing and crusting up and causing a jamming and has to ber cleaned out periodically? The key comment here is that the atmosphere is the problem and inert gases should be introduced in areas where DRI is handled. Nitrogen is the best, probably.

The design should be also looked at to see if changes can be made to a vertical mechanism that will not allow accumalation of dust or materials.

As soon as we have more information we can make more comments.

T.C.Inc.-tcinc002@aol.com ■

Please post the general arrangement drawing.

Regards, ■

Do you know the operating clearances within the cylinder? In earlier days one of my respected colleagues custom designed a large cylinder and was asked by the Technical Director if the thing had been checked for cross cornering. At that time nobody in our drawing office had a clue and so he (very learned TD) tried to explain the concept to us all. I still don't really understand. If you examine the piston to bore clearances and the rod to annulus bush clearances for generating 3 point contact as the rod misaligns and takes the piston with it in both hot and cold operation it might tell you something. Ensuring the stated tolerances have been achieved in the first place involves a bit of paperwork. Maybe this cylinder was built before the days of as-built drawings (I've never seen one yet) so inspection reports (usually thrown away by purchasing who don't know what they are buying in the first place) will have to suffice.

Crusting has been mentioned as a likely cause of jamming which indicates that your rod wiper is perhaps inadequate or on the point of collapsing. If that is the case then you would have to replace the wiper so why not fit new seals throughout and just before you reassemble the piston you might like to slide a bellows over the exposed rod. Of course if the rod clevis is detachable fitting a bellows will be much easier. While the thing is in pieces check for cross cornering just in case. Then you're covered comprehensively. ■

Originally Posted by IsmailDRI

Hi.. Anybody in DRI plant have a pneumatic cylinder as actuator for the fines diverter? Did the diverter jammed frequently?

Is the diverter getting jammed or the pneumatic cylinder ? We do have gates in DRI plants. The diverting mechanisms are mechanical actuators. Not pneumatic.

Please disengage the cylinder from the gate and take trial, to know what causes the jamming.

Regards, ■

Dear Ismail,

Can you pls share GA drawings and your email so i may present to you a better solution? Thanks

Umer ■