The phrase "for use as a" is correct and usable in written English.
This phrase is used to describe an intended purpose of something. For example, "The software was designed for use as a communication tool."
Collect overflowing juice for use as a sauce.
Chop bacon finely, for use as a garnish.
Any paragraph could be hoisted out for use as a model in a writing class.
An old carriage house was moved, reassembled and transformed for use as a library.
Congress passed a bill authorizing Greece to turn it over for use as a memorial.
* A warning on an electric router: "This product not intended for use as a dental drill".
In 1836, his descendants donated it to the city for use as a park.
The carriage house will be restored for use as a visitors center, gift shop and offices.
Current law prohibits possession of substances specifically "for use as a weapon".
AstraZeneca is now testing a failed diabetes and obesity drug for use as a glaucoma treatment.
It also has a full basement conducive for use as a wine cellar.
