PTFE backup rings

The PTFE teflon backup ring kit comes complete with 14 split PTFE teflon backup rings and 14 black nitrile orings.  The backup rings are split at a 45 degree angle for ease of installation.  Installing solid backup rings can be difficult for the DIYer.

The PTFE rings are separated into individual packets within the oring bags.  Locking valves have three backup rings, one big ring and two smaller rings.  Control valves each have four rings, one large, two medium size, and one small size.

Once the valve block has been removed and disassembled it's time to get started.  Start off by removing the plunger from the locking valves

Remove the old rings from the valves.  The existing rings are easily removed using a razor blade to cut them and then simply remove.  I always recommend removing the rings from one valve at a time and use the other as reference during reassembly.

Layout all the rings in the order they go. 

Spiral the backup rings to make them smaller in order for the ring to maintain tight clearances and ease of inserting valve into block.

Walk the rings down the valve while trying not to stretch it out to much.

Once the backup ring is in it's place you may notice a slight gap at the split.  This closes up with pressure around the ring simulating the valve installed in the block.  Follow the same process for the remaining rings.

Repeat the process on all other valves and reinstall into the valve block.  Use plenty of lubrication while installing. They do not require too much pressure during installation.  Twist the valves back and forth a few degrees while applying pressure into the valve block.