When selecting a steam trap, why is it necessary to multiply the trap’s discharge capacity by a safety factor?

1. Since the drainage capacity of a steam trap is measured under conditions of continuous drainage, but virtually all steam traps do not drain continuously in actual operation—instead, they typically drain intermittently—it is essential to take into account the downtime during actual operation.
2. Even when the capacity of a steam-using piece of equipment has been determined, that capacity refers only to the load under normal operating conditions. When the equipment begins operation (at startup)—during what is known as the “warm-up phase”—both the equipment itself and the material being heated are at room temperature, resulting in a significant increase in steam consumption. In other words, steam-using equipment often generates a large amount of condensate during the warm-up phase.

For these two reasons, when selecting a steam trap, the trap’s discharge capacity should be multiplied by a safety factor.