Polyethylene piping systems are defined or specified using two important criteria: the ASTM D3350 cell classification and the ASTM F412 thermoplastic piping material designation code. The ASTM D3350 consists of a series of six digits followed by one letter. The six digits equate to the specified level of performance required in six separate physical properties defined within the standard. The final letter specifies the color or UV-resistance requirement. Taken together the D3350 cell classification establishes a minimum range of technical performance for the PE compound used to produce the pipe.
The F412 thermoplastic piping material designation code further defines the performance requirement of the pipe produced from a particular PE compound. This code consists of an abbreviation for the basic material as defined within the ASTM standards. The standardized abbreviation for polyethylene is the term “PE”. This basic polymer designation is then followed by a series of four digits. The first two digits relate directly to specific physical properties for the compound as defined within ASTM D3350. The last two digits are the long-term hydrostatic stress rating as recommended by the Hydrostatic Stress Board of the Plastic Pipe Institute in hundreds of psi. The long-term hydrostatic stress rating is the hydrostatic design basis (HDB) multiplied by the appropriate design factor (DF).
ISCO’s Snap-Tite pipe features the patented Snap-Tite joining system which will ensure an easy-to-install, reliable, water-tight seal. Snap-Tite is constructed of solid-wall polyethylene pipe and provides flexibility for lining obstructed culverts with the possibility of offset joints or slight bends.
|Pipe SDR||lbs/ft||I.D.||Minimum Wall Thickness|
|10″ (10.750 OD)||32.5||4.75||10.088||0.331|
|12″ (12.750 OD)||32.5||6.67||11.966||0.392|
Several studies have revealed that the largest expense on culvert projects is not the pipe itself, but the installation, inspection, maintenance, road repair, and liability. Because the Snap-Tite Culvert Lining System is so easy to install, it reduces your overall culvert renewal costs. Snap-Tite saves on labor costs by eliminating the time-consuming process of cutting and repairing roads. There’s no need for specialized equipment, so you save money on costly rentals and labor. And just think, during down times from mowing or snow removal, your existing highway crews can be productive by lining deteriorating culverts. but don’t take our word for it, examine the comprehensive cost justifications performed by these states. Read more
Snap-Tite has an extremely smooth inside surface and maintains its excellent flow properties throughout its service life due to its excellent chemical and abrasion resistance. Because of its smooth walls and non-wetting characteristics, a higher flow capacity and a reduced friction loss is possible. Snap-Tite typically has a Manning roughness coefficient of 0.009 and a Hazen Williams flow factor of 155. The charts on the following pages demonstrate how the Snap-Tite system gives you a more durable pipe with a smaller ID that carries as much, if not more fluid than the original pipe!
Standards important for Snap-Tite® HDPE pipe relate to the resin the pipe is made from and the standards related to manufacturing sizes and tolerances.
Since one-third of exisiting culverts are arched, Snap-Tite® again has come up with a solution: oval pipe. It has the same benefits as smooth-wall HDPE Snap-Tite®, yet made for a better fit into an existing arched culvert.
The Snap-Tite® Culvert Lining System actually outperforms both the round and oval concrete and corrugated metal pipes it rehabilitates.
Lightweight, flexible, durable HDPE has an indefinite service life and the Snap-Tite® culvert lining joining system assures a water-tight seal at all joints.
Flow in Lined CMP
|CMP Size (inches)||Equivalent Snap-Tite Round OD||Outside Liner Dim(in)||Inside Liner Dim(in)||Flow Q(cfs)||Snap-Tite % of Flow|
|* flow is based on slope of .1% HDPE n=.00914 / CMP n=.024|
Flow in Lined RCP
|RCP Size (inches)||Equivalent Snap-Tite Round OD||Outside Liner Dim(in)||Inside Liner Dim(in)||Flow Q(cfs)||Snap-Tite % of Flow|
|* flow is based on slope of .1% HDPE n= .00914 / concrete n=.015|
Ask your Snap-Tite sales rep for additional sizes