Apr 25, 2003

Twenty-Four Years and Still Sealing Pipe Penetrations

Products At Work

The Link-Seal Model-C sealing element is manufactured from
EPDM black rubber that handles temperature ranges -40 to +250°F. During installation, the rubber link is
compressed to fill the annular space between the pipe's outer diameter (OD)
and the wall penetration by means of pressure plates molded from Reinforced
Nylon Composite and formed so that pressure is transferred to the sealing
element uniformly. As a
hydrostatic seal, Link-Seal modular seals are rated at 20 psig (40 feet of head).

Link-Seal modular seals were installed in 1979 by the
Limbach Co., on the original Ypsilanti Wastewater Treatment Plant. Michael Jessee, the plant maintenance
superintendent, said that the more than 100 pipe seals in use throughout the
plant have shown no noticeable leaks in the 18 years he has been at the
plant. This is due in part to the
design of the 15 available models of Link-Seal modular seals capable of
handling from a 1/2"-OD pipe up to a 120"-diameter pipe.

These seals are designed for use as a permanent seal. Seal
elements are specially compounded to resist aging and attack from ozone,
sunlight, water and a wide range of chemicals. The carbon bolts and nuts
feature a zinc dichromate proprietary organic corrosion inhibiting coating. For
extreme treatment plant water conditions, 316 stainless steel bolts and nuts
are used.

For the Ypsilanti Wastewater Plant's 2002, $100
million plant expansion, the consultant engineer Tetra Tech MPS of Ann Arbor,
Mich., specified Link-Seal modular seals as a prime wall penetration sealer.
Marty Schlitt, project manager for the John E. Green Co., the awarded
mechanical contractor, said that there would be more than 100 sealing
applications through 48" pipe with multiple cored holes. Schlitt prefers
the Century-Line sleeves for the cast in-place applications. These HDPE sleeves
will eliminate rust stains on the walls resulting from moisture condensing and
dripping from the original installed steel sleeves. HDPE also provides
excellent resistance to acids, alkalis and other organic solvents found in
treatment plant environments.

About the author