BUZZ-Rotork rallies after earnings beat and acquisition
** Rotork (LSE: ROR.L - news) rises 4.3 pct after earnings beat expectations, among best performing UK midcap
** Pre-tax profits beat driving returns, traders say (H1: £64.11 mln, a 2 pct beat, according to Thomson Reuters (Dusseldorf: TOC.DU - news) data), with orders also ahead
** Co also announce small acquisition from Spirax-Sarco
** Decent volumes with 45 pct stock's 30-day average volumes in the first 80 minutes of trade
(RM (LSE: RM.L - news) : alasdair.pal.thomsonreuters.com@reuters.net)