English to Russian Tech/Engineering Engineering (general)

Речь идёт об испытании строительных конструкций и материалов на огнестойкость. Именно sandbox burner создаёт пламя, которое воздействует на образец. Сжигает пропан. О sandbox burner говорится:
"Shape: right angled triangle (top view) with two equal sides of 250 mm, height 80 mm, bottom closed except for a 12,5 mm pipe socket at the gravitational centre, top open. A right-angled triangular perforated plate shall be positioned in the burner at a height of 10 mm above the bottom. Metal gauze with a maximum mesh size of 2 mm shall be positioned at heights of 12 mm and 60 mm above the bottom. All dimensions shall be within ± 2 mm.
Material: box made of 1,5 mm stainless steel, filled from bottom to top with, successively, a 10 mm void, a layer of pebbles within a size distribution of 4 mm to 8 mm up to a height of 60 mm, and a top layer of sand within a size distribution of 2 mm to 4 mm up to a height of 80 mm. The metal gauze is used to stabilize the two layers and prevent the pebbles from entering the gas pipe socket. The pebbles and sand used shall be rounded (river) stones, not broken ones".

Заранее спасибо!