black steel protection

Check with your insurance underwriter, if you have one. They will set you straight.

Good drainage is a must when going underground with steel pipe.

To protect from external corrosion there is available Denzo tape a sticky wax impregnated tape which is applied when laying it in the ground.

Internal corrosion is a function of dissolved oxygen in the water if the pipes are not used for long intervals this oxygen will be depleted by oxidation and the rust process will slow down. You could fit replacable sacrificial anodes at various points if it is a concern.

What thrust do you wish to support?

Clean the pipe and fittings. Apply mastic and tape made for the purpose over all surfaces of all pipe, valves, and fittings, from underground to 6" above ground. Install anodes and Cathodic Protection Test Stations at required intervals. Create a periodic test inspection schedule to assure pipe is positive with respect to soil. Install new anodes as required.

How many feet or meters do you need to place and has the soil been tested for PH, Chlorides, and other potential corrosion causing factors?

Does your budget allow for OD and ID Coatings?

Have you thought about FBE on OD or some type of flow liner on ID.

Costing can vary, depending upon methods used.

Safety and performance of the system when needed should warrant a first class anti corrosion system, with life a close second.

Thrust blocks can be poured in place or purchased ready to use from several manufacturers.

Dear Sir,

I strongly suggest that you use Ductile Iron Pipe for buried water/fire service, especially if it is installed with minimal soil cover above the pipe and in areas carrying vehicular traffic. Black Iron pipe IS NOT the best material for your underground installation. Proper trench bedding and backfill is essential for a successful installation of any buried pipeline. Same is true with the proper sizing and construction of concrete trust blocks located at fittings and dead ends......they're wholly dependant on the maximum pipeline working pressure (with surge allowance added), pipe O.D. and the allowable passive soil bearing pressure of the encountered soils. Not all soils are created equally!

As far as installation of your water supply piping is concerned, I suggest that you study several applicable sections of the AWWA Standards, a good textbook covering water supply & construction, and finally, consult with the operator/owner of the water supply agency that will be supplying the water to your project.

Have a great sunny day!

as other said the best way to protect steel underground is a combination of a good coating plus cathodic protection.

http://www.bushman.cc/pdf/corrosion_theory.pdf

http://www.corrosionist.com/cathodic_protection_impressed_current.htm

S

rust & corrosion protection