Chromatography Forum

Hope someone here can comment on my current issue. We have a Waters RI detector, which we've determined has a clog in the input line from the column. While we've isolated the clog to the line as marked in the picture, we can't seem to get the line loose from the "T" block at the left. While the nut has been fully removed, the ferule appears to be 'welded' into the block. Before I apply excessive brute force to this line, and possibly wreck the entire block, does anyone have any suggestions for getting this fitting out of the block?

Thank you for your help!
Jay
P.S. for some reason, the image insert does not appear to work. The picture I tried to attach can be seen at https://www.jjpowellfamily.com/ourcloud ... zkGdfoNan4

What was the mobile phase composition before the clog? I'm guessing that there may be a buffer that salted out and is causing the blockage. I would try to submerge that assembly in something to solubilize the buffer, maybe high aqueous, then probably try to soak in a higher organic to see if that helps to loosen the blockage.

Like the idea from itspip

maybe immerse it in hot water amd ultrasound?
Heat in general, then force

Another idea may be to connect the left side to a pump and close every other port and end of the clogged line; just leaving the stucked port unscrewed. Then slowly start pumping and let the pressure build up and hopefully losen the fitting from inside. Maybe even a leak may help in lubricating the fitting.

Just ideas

Thank you Hollow and Itspip for your suggestions.
After taking out the entire tubing assembly shown in the picture, from the inlet port, along with the "T" block, disconnecting the lines from either side of the 4-way fitting, and removing the line going to the cell, I found why I couldn't remove the short length of tubing I suspected was clogged: The fine tubing is concentric with the larger tubing on the other side of the "T" block, where the flow from the RI cell passes through outside it as a counter-flow heat exchanger. After getting the entire assembly out, I was able to back flush it and clear the clog.
Thank you both again for your suggestions.
Jay