In steam systems that have not been maintained for 3 to 5 years, between 15% to 30% of the installed steam traps may have failed—thus allowing live steam to escape into the condensate return system.
In systems with a regularly scheduled maintenance program, leaking traps should account for less than 5% of the trap population. If your steam distribution system includes more than 500 traps, a steam trap survey will probably reveal significant steam losses.
Recommended Steam Trap Testing Intervals
• High Pressure (150 psig and above): Weekly to Monthly
• Medium Pressure (30 to 150 psig): Monthly to Quarterly
• Low Pressure (Below 30 psig): Annually
Example In a plant where the value of steam is $4.50 per thousand pounds ($/1,000 lbs), an inspection program indicates that a trap on a 150 psig steam line is stuck open. The trap orifice is 1/8 inch in diameter.
The table below shows the estimated steam loss as 75.8 lbs/hr. By repairing the failed trap, annual savings are: Savings = 75.8 lbs/hr x 8,760 hrs/yr x $4.50/1,000 lbs = $2,988/yr