The Challenge - The Velan Idea
Due to the fact that the current product offerings in the marketplace in
1947 did not handle high pressure – high temperature application well,
Velan Engineering had to think outside the box as far as steam trapping.
All manufacturers of the day discharged condensate at steam temperature.
Velan looked at drip leg applications and asked, “What advantage is
there in discharging condensate at saturated temperature?” “If
I lowered the temperature of the condensate a determined amount,” Velan
surmised, “wouldn’t less flash steam be created in the condensate
return system, and wouldn’t less turbulence occur across the seating
surface?” This was the beginning of the Velan theory of steam
trapping for the marketplace.
DISCHARGE AT NEAR-TO-STEAM TEMPERATURES
The standard Velan steam trap opens only when condensate temperature drops
15-20ºF below saturated temperature. During this time the comparatively
small quantity of near-to-steam temperature condensate collects in
the drip pockets. Standard drip pockets, following established good piping
practice, is all that is required to keep equipment free of condensate and
eliminate steam leakage.
The drop in temperature of the accumulating water causes a slight drop
in pressure. Water particles flowing with steam can easily find their way into
the drip pocket. Because the trap is under water most of the time, leakage
of steam is impossible. Trap remains tight in presence of superheat.