Water hammer can occur in steam and water pipes and headers, and can be very dangerous, especially at start up. A power company located in the Southeast occasionally experienced severe water hammer in their steam generator supply pump system, causing their seals to fail repeatedly and costing $1 million per day in downtime. This plant looked to EagleBurgmann for a sealing solution due to their rugged mechanical seal designs and seal knowledge.
The plant’s water hammer occurs when air gets trapped in the discharge line of the pump and they can’t remove it. Since this is extremely hot water under pressure, it turns to steam when it hits the air pocket and is extremely violent when it happens. This change from liquid to gas would dislodge seal faces and cause leakage, and in one instance, actually blew the seal sleeve out of a seal.
The prior seals that failed utilized set screws, which would fail upon water hammer. These set screws were aligned with the shaft only, making them unable to handle the extreme pressure surges.
After careful review of the pump data, EagleBurgmann recommended a SHFV mechanical seal, which features a shrink fit carbon stationary disk and a positive driving and holding mechanism with the shrink disk to hold it to the shaft.
SHFV Seal Features
- Stationary multiple springs and integrated pumping screw
- Pressure stabilized reinforced carbon seal face with hardened metal support ring
- Material combination for optimal heat transfer at seal faces
- Robust design prevents seal face distortion at high pressure ensuring a stable lubricating film
- Safe and low leakage behavior in high speed and pressure applications
Four seals were installed in May 2011 and have been performing well with no failures to date. “This was the first sale for EagleBurgmann in this plant, and it’s really helped us gain the customer’s confidence in EagleBurgmann products and solutions,” stated Gerry Koren, Territory Manager.
“I anticipate this to be a long-standing relationship, and look forward to additional opportunities within this plant on their non-safety related equipment."
For more information on EagleBurgmann SHVF seals, please contact us at firstname.lastname@example.org.