Distribution transformers drying oven

we are iraqi company, working in the field of supply and delivery for machine equipment’s and measurement instrumentation, we have received requests from our electricity directorates to supply dry oven for distribution transformer .
the main specification for the oven as following :
1) the rated power for the distribution transformer that we want to dry it up to 1000 kva .
2) the temperature rise up to 150 c .
3) the inner (work size) dimension of oven is