What Thickness of Gland Packing should I Buy?

[DBA Forum (B) - Keith Wren]

What about the type of packing Balliol? There's the traditional hemp and also PTFE so does the latter have any benefit?

Keith

[DBA Forum (B) - Paul Hayes]

Hi Keith / Balliol, I hope you do not mind me putting my tuppence worth in on this one. Best Paul

PTFE gland packing is for specialist use in the food and pharmaceutical industry. It is not really suitable for high speed rotating shafts which handle water that contain sediment such as grit and clay as is the case of prop shafts.

I once had the pleasure of repacking a stern tube that had been stuffed with PTFE, where due to over tightening the temperature had risen and the PTFE melted. The molten PTFE on cooling even formed a plug in the grease hole stopping further lubrication.

It was a devil of a job getting it out of the stuffing box and replacing it with traditional graphite impregnated cotton packing.

For details of packings available, and there uses go to Crane Packing's web site.

http://www.johncrane.com/Products/Packing.aspx

and

http://www.johncrane.com/Products/Packing/894-1336-1340.aspx

Hope this helps

Paul Hayes