UPDATE 1-Oil firm EnQuest's cash flow at $138 mln in first half

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ABERDEEN, Scotland, Sept 5 (Reuters) - North Sea focused oil firm EnQuest more than doubled its free cash flow to $138 million in the first half, boosted by bigger production, it said on Thursday, reiterating its output guidance of between 63,000 and 70,000 barrels per day this year.

The group, which had a market cap of around $380 million on Wednesday, is planning to drill two wells in the Western Flank area of its Kraken field in 2020, where it sees a reservoir of around 100 million barrels.

EnQuest is chipping away at its debt pile, which was around $1.6 billion at the end of June, down from around $1.77 billion at the end of last year.

EnQuest is due to pay back $25 million next month, ahead of a $125 million payment in April, its Chief Financial Officer Jonathan Swinney said.

Its earnings before interest, tax, depreciation and amortisation (EBITDA) reached $526 million in the first half, up from last year's $312 million, mainly boosted by increased output on the back of its Magnus field and hedging gains.

It reiterated its target to keep debt at below two times EBITDA by year-end.

For the rest of the year, EnQuest has hedged 3.9 million barrels at an average floor price of $66 a barrel and 0.7 million barrels at an average floor price of $56 a barrel.

It produced around 55,000 barrels last year.

(Reporting by Shadia Nasralla; editing by Jason Neely and Toby Chopra)