Join Date: Mar 2007
Location: New England
Thanked 7 Times in 7 Posts
Rep Power: 10
The beauty of packing material is that if it ......
is close, it should work, because it compresses slightly. Packing material usually comes in 1/16 inch increments, so if you think 1/4 is too small, go to 5/16. As far as metric, I am not aware of any on this side of the pond, but that shouldn't matter.
1 inch has 25.4 mm in it, so 1/16 of an inch is about 1.5 mm, if you think that you need a 4 mm dia. packing, choose the closest to it; 3/16 inch.
The observation about the packing being too small because you have 4 rings is not related. The number of rings has more to do with the gland depth, than the gland space around the shaft. Some folks need only 2 wraps, some folks need 5 or even 6. 4 is a pretty standard number. If your bottomed out, that may be that the packing is compacted, so just change the packing out. When getting the new pack, measure the gland width (against the shaft) and go from there.
When repacking the flange, put two rings in, hand tight the rings down, and keep putting in rings, one at a time, until you just get the packing nut to screw on about 1.5 to 2 full turns hard hand tight. Then tighten well and test the drip rate.
If you liked my advice/response, give me some rep points. If you didn't......well what do you expect, it was free.