What kind of pipes can be used for ammonia NH3 ? and why?

 If there is a combination of low temperature and high pressures (below -29 deg c and4 bar pressure) then use ASTM A333 otherwise either ASTM A106 grade B or ERW API5L would be used dependant on availability and cost.

only steel or ductile iron should be used for ammonia systems because ammonia will react rapidly with copper, brass, zinc and many alloys

 [ LEED ] leadership Energy Environmental Design, ist is a tools to create of a concrete and dynamic company, that have a concern to our environment and to lead to the  others.

Pipes used for low temperature in Ammonia are ASTM A333 and for slightly higher temperatures A106 Or A53 can be used which is normal practice.

A333 is expensive.