In the first article we discussed the spindle seal and whether or not the spindle was equipped with a lubrication fitting making it possible to lubricate or seal the valve in case of an external leakage out past the stem seal. The next item on the list was lubrication fittings and connecting channels to the seat/ball seal. Looking back 30 years or more when all ball valves were soft seated and easily scratched and worn on the seat seal there were secondary seal injection ports on the valves where sealing component could be injected to seal a valve in case of an internal leak. Nowadays it is common to use hard metal or tungsten carbide seals on the seats making them much more resistant towards scratches and operational wear. In the minds of some, this makes the lubrication fittings and the connecting channels unnecessary and, in fact, a danger to the safety of the valves as they are regarded as possible leak- points and therefore taken away.
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