C. Protective Coatings

Protective coatings schedules (if any) shall be submitted, showing shop and field surface preparations, materials, methods of application, dry film thickness and tests for defects, all in conformance with this Section.


40.1.3 Marking

Each length of pipe and fitting shall be marked with the following:

• Manufacturing standard
• Manufacturer's name
• Manufacturing date
• Nominal diameter in mm
• Inside and outside diameters in mm
• Pressure rating in bars
• Inspection mark
• Coupling “homeline” position on spigot ends
• Serial Number

40.1.4 Not More than One Manufacturer

Pipes, couplings, fittings and valves for each component classification shall not be supplied by more than one manufacturer, except with the Employer's approval.

40.1.5 Test Certificates

All pipes, couplings, fittings and valves delivered to the site shall have been tested (referred to hereinafter as “works test”) in accordance with ISO standards or other approved equivalent or better standard. The Contactor shall furnish the Engineer with the manufacturer's test certificates for each consignment before each delivery begins.

The Engineer and/ or the Employer reserves the right to inspect the pipes, fittings and valves to be supplied for the works at the place of manufacture and to witness works tests. The Contractor shall provide the equipment and labour necessary for carrying out the inspection.

40.1.6 Service Conditions

All sanitary sewer pipes and appurtenant materials shall be suitable for carrying domestic wastewater at temperatures of up to 50Celsius with sulphide concentrations up to 50 mg/L.

All buried pipes and appurtenant materials shall be suitable for immersion in corrosive groundwater. Groundwater characteristics shall be ascertained by the Contractor.

40.1.7 Materials

Acceptable materials for pipes and appurtenances are as follows:
A. Force Main

(i) Flanged Cast Iron (CI) with working pressure of 325 Ft
(ii) Asbestoes Cement Pipes (AC) with working pressure of 300 Ft
B. Interconnecting Pipes between Treatment Units

(iii) Flanged Cast Iron (CI) with working pressure of 325 Ft
(iv) Asbestoes Cement Pipes (AC) with working pressure of 300 Ft

C Chemical Conditioning & Dosing

High Density Polyethylene (HDPE) with 5 bar working pressure

D. Water Supply

(i) Galvanized Iron Pipe medium class
(ii) Polyvinylchloride Pipes with working pressure of 300 Ft

40.1.8 Basis of Acceptance

The acceptability of the pipes and fittings will be based on the results of tests carried out at the manufacturer's plant and/ or at the Contractor's expense and the result of any independent testing carried out by the Employer or his agent. The frequency and type of tests required for each pipe material are given in the following Sub-Sections and certified copies of all records of inspection and test results shall be submitted to the Engineer.


40.2 MATERIIAL SPECIFICATIONS & STANDARDS

40.2.1 Asbestoes Cement (AC) Pressure Pipes & Couplings

AC Pipes and couplings shall conform to requirements of international organization for Standardization Recommendation R 160 “Asbestos Cement Pressure Pipe” or BS 486: 1973 “Asbestos Cement Pressure Pipe” for the specified class. The test and working pressures for various classes of pipes should be as under:
Class Test Pressure
Meter (Feet) Working pressure
Meter (Feet)
12 120 (400) 60 (200)
18 180 (600) 90 (300)
24 240 (800) 120 (400)


40.2.2 Cast Iron Pressure Pipes and Fittings:

Cast iron pressure pipes and fittings, socket / spigot and flanged types, shall conform to the requirements of BS 4622: 1970. Cast iron threaded companion flanges, shall conform to the requirements of BS 10:1962 (Table D). The working pressures for various classes of pipes and fittings should be as under:

Class Working Pressure Meter (Feet)
1 100 (325)
2 125 (400)
3 160 (520)