March 18 (Reuters) - Oilfield equipment makers Dril-Quip and Innovex Downhole Solutions plan to merge in an all-stock deal, the companies said in a joint statement on Monday, months after Innovex filed to go public in the United States.

Shares of Dril-Quip, which has a market value of around $800 million according to Refinitiv, rose 7.5% to $25.5 in extended trading.

Both Dril-Quip and Innovex provide engineering equipments and technologies to companies focused on the oil and gas industry, where there has been a wave of consolidation recently.

The merger will see Dril-Quip stockholders own about 52% of the combined company, with the rest going to Innovex stockholders.

The combined company will be named Innovex International, Inc, and its common stock is expected to trade on the New York Stock Exchange under a new ticker symbol, "INVX".

The deal, expected to close in the third quarter of 2024, will see Innovex CEO Adam Anderson lead the combined company headquartered in Houston, Texas.

Citi is serving as lead financial advisor to Dril-Quip, while Goldman Sachs & Co. LLC is serving as lead financial advisor to Innovex.

(Reporting by Mehnaz Yasmin in Bengaluru; Editing by Devika Syamnath)