-3.03 CONSTRUCTION Not Used 66-3.04 PAYMENT

66-4.02 MATERIALS

Composite steel spiral rib pipe must be fabricated by continuous helical lock seam under section 66-1.02E(2)(c)(ii). Three rectangular ribs must be spaced midway between seams with ribs 3/4 inch wide by 3/4 inch high at a maximum rib pitch of 7-1/2 inches on center. The rib pitch measured at right angles to the direction of the ribs may vary by ±1/2 inch.

Pipes formed from polymer precoated sheets must comply with ASTM A742/A742M, Grade 10, except the sheet side for the pipe interior must have additives that will enhance the bond of the sheet to the extruded polyethylene liner. Before application of protective coatings, the galvanized sheet must be cleaned with an alkaline cleaner followed by chrome pretreatment.

Steel sheets coated with zinc metallic coating must comply with ASTM A929/A929M.

The polyethylene for filling the ribs and the internal liner must be virgin resin. The virgin resin quality characteristics must comply with the values in the following table:

Galvanized nuts, bolts, and washers must comply with section 75-1.02B.

Expanded rubber gaskets must comply with ASTM D1056, Type 2, Class C, and Grade 1. Protect gaskets from excessive exposure to heat, direct sunlight, ozone, oil, or grease. Gaskets placed over spiral ribs must have a groove routed to match the rib's depth and width before installation. Do not substitute O-rings for gaskets.

The gasket adhesive must be 1 part urethane elastomeric joint sealant under ASTM C920, Type S, Grade NS, Class 25, Use NT, A, and M. Use the sealant within 9 months from the date of manufacture. Store the adhesive at an ambient temperature of 80 degrees F or below. Do not use any adhesive that has been stored at temperatures exceeding 80 degrees F.

Manufactured pipe joints must comply with section 61-2.01D(2)(b) for sleeve joints.

Each standard and random length of pipe must be marked clearly in permanent letters not less than 1/4 inch in height at intervals of 5 feet or less with at least the following:

1. Manufacturer’s code and name or trademark

2. ASTM A978/A978M

3. Nominal pipe size
Each coupling band must be marked clearly with at least the following:

1. Manufacturer’s code and name or trademark

2. ASTM A978/A978M

3. Nominal size

Store pipes in unit packages with the pipe ends protected from deformation and damage. Support unit packages with racks or dunnage to prevent damage and bending. Stack unit packages to ensure that the weight of the upper units will not cause deformation to pipes in the lower units. Do not store pipes adjacent to electrical or exhaust heat sources.

Do not expose pipes to direct sunlight for periods exceeding 30 days. Cover pipes with an opaque sheeting material to provide sun protection. Arrange the opaque sheeting material so that it provides adequate air circulation around pipes to reduce excessive heat accumulation. Ship gaskets in containers that will prevent damage from UV exposure and handling. Do not store gaskets near electrical or exhaust heat sources or where they will be exposed to the sunlight for more than 48 hours.

66-4.03 CONSTRUCTION

Cover the ends of installed composite steel spiral rib pipe that were not backfilled after installation at the end of each day.

Repair damaged polymeric pipe coatings on pipe and pipe fittings. For polymeric coatings with damaged areas less than 36 square inches in area, repair breaks and scuffs under the manufacturer's recommended repair procedures. Do not install a pipe if the individual breaks or total area of the breaks exceeds 36 square inches in area or if the total area of the breaks exceeds 0.5 percent of the total pipe surface area.

The polymer repair material must be one of the following:

1. Denflex Coating - Dennis Chemical Company, St. Louis, MO

2. Scotch-Clad 1706 Protective Coating - 3M Company, St. Paul, MN

3. Ranbar Trispec TPC-515-7 Black Synthetic Coating - P.D. George Company, Manor, PA
Clean and dry surfaces to be coated. The repair coating must be at least 0.010 inches thick after hardening and must bond securely and permanently to the pipe. Apply 6 coats if the thickness of the repair coating is not measured. Allow 30 minutes drying time between the coats.