Kiradech, the current Asian Tour Order of Merit leader, resumed his round on hole 12 at Blackstone Golf Club. The 23-year-old birdied the par-four before picking up further shots on the 14th and par-five 18th to move to seven-under, level with the two overnight leaders.
The 23-year-old has been in fine form in events sanctioned by the European and Asian Tours, finishing fourth in last month's Avantha Masters in India before claiming his maiden European Tour title at the following week's Maybank Malaysian Open.
Kiradech is now bidding to become the first player since South African Branden Grace at the start of last year to triumph in consecutive appearances on The European Tour.
"I got experience and a lot of confidence before coming here this week, although the weather is quite different from Malaysia," said Kiradech, who won his first Asian Tour title at the 2011 Sail Open in India.
"I was quite lucky in the second round, as the wind was quite quiet. I know I can make a score and my form is good from Malaysia. My driver and putter are both great so hopefully I can stick to the game plan."
Kiradech, Arnond and Ormsby - all Asian Tour members - were one stroke ahead of South African Jbe Kruger (67), another Asian Tour player, and four European Tour winners - Alex Noren (67) of Sweden, Englishman James Morrison (66), Spaniard Jose Manuel Lara (67) and Scot Stephen Gallacher (68), who won in Dubai in February.
Korean youngster Kim Gi-whan (72), one of five first-round co-leaders, was among four players at five-under.
World Number Seven Louis Oosthuizen (71) was among 14 players at four-under, including China's Alex Wu Ashun, who shot the low second round with a 65, defending champion Bernd Wiesberger (69) of Austria and 2010 winner Marcus Fraser of Australia.
Korean quartet Kim Hyung-sung (69), Kang Kyung-nam (68), Joo Heung-chol (70) and Han Min-kyu (69) were among those at four-under, while Korean stars YE Yang (72) and KT Kim (68) at two-under can expect strong support from the Blackstone galleries.
The delayed third round started at 11.50am, due to weather-enforced suspensions on Thursday (two hours, 20 minutes) and Friday (one hour, 20 minutes).