Have you looked at Grey Matter Cases ( https://www.miningrigs.net/product-category/server-cases/ ).

They have a all in 1 Rack mount shelf in a 6U format designed to secure 3 Bitmain's Antminer S7/S9 & 3 power supplies.  Hash power could be 3x 4.7/13.5 (totaling 14.1 / 40.5 ) TH/s respectively, depending how you configure them.

Hope this helps.

  /s TuffToad