непосредственно перед

I

The box is located immediately ahead of the drive head.

A separator is installed just ahead of the main turbine shop.

The work material is passed through an induction heating coil immediately in advance of the forging rolls.

II

The minerals are added to the basic solution just before infusion.

The reaction mixture was prepared immediately (or just) prior to (or before) use.

Источник: Русско-английский научно-технический словарь на Gufo.me