The phrase "a number of drafts" is correct and usable in written English.
It can be used when referring to multiple versions or iterations of a document or piece of writing that have been created or revised.
Example: "After reviewing a number of drafts, we finally settled on the final version of the report."
Alternatives: "several drafts" or "multiple drafts".
"I recall that there was a number of drafts of old financial statements that I had retained, still had copies of, that I gave her.
George W. Bush, the Republican nominee, put his speechwriters through a number of drafts, but like most candidates did not do any writing himself.
For detailed comments and criticisms on a number of drafts I would like to thank Thomas Pogge.
After a number of drafts, Mabe and Alexander finally created a version they felt was "perfect for the movie".
The 3rd Battalion was one of these and upon mobilisation it was brought up to its wartime establishment with a number of drafts of national servicemen recruited from regional New South Wales and the Australian Capital Territory.
Birbiglia was already a number of drafts into writing a screenplay based on his second one-man show "My Girlfriend's Boyfriend" when he set that aside to begin work on what would become "Don't Think Twice".
Here goes nothing: Orlando could offer Grant Hill and a number of draft picks, or Mike Miller, Bo Outlaw, John Amaechi and some scrub who makes too much money.
On Sept. 26th in the first of a number of draft-evasion cases pending in the federal court, an "independentista" named Edwin Feliciano Grafals was sentenced to one year in prison for refusing induction - a sentence that was later reduced to one hour.
Or, if the team sees itself in a time of rebuilding, as the Polian firing suggests, might they consider trading Manning for a number of draft picks or younger players who could shore up Luck's team for years to come?
A number of drafting iterations were completed before the group agreed upon a final document, a copy of which was sent to each panel member for review.
A number of draft decision aids (including workbook, audio transcript, and worksheet), were developed and each subjected to pilot testing and revision as we obtained feedback.
