UPDATE 1-EQT Midstream Partners plans to price IPO at $19-$21 per unit

June 18 (Reuters) - EQT Midstream Partners, the midstream arm of natural gas producer EQT Corp, said it expects to price its initial public offering at between $19 and $21 per common unit.

The Pittsburgh, Pennsylvania-based company last week said it will offer 12.5 million common units in the up to $250 million IPO, for which it had filed in February.

EQT Midstream said it will own, operate, acquire and develop midstream properties in the gas-rich Appalachian Basin.

Citigroup, Barclays Capital, BofA Merrill Lynch, Credit Suisse, JP Morgan and Wells Fargo are acting as joint book-running managers to the offering, the company said in a regulatory filing on Monday.