Japanese electronics conglomerate Toshiba Corp posted a better-than-expected 178 percent rise in quarterly operating profit on Tuesday, boosted by strong overseas profits in the firm's social infrastructure division despite sluggish chip sales.

Toshiba, which manufactures products ranging from light bulbs to nuclear reactors and is the world's No.2 NAND flash memory chip maker, logged an operating profit of 11.47 billion yen ($147 million) in the April-June quarter, bouncing back from 4.12 billion yen in the same period last year, when Japanese corporate earnings were hit by the aftermath of the earthquake and tsunami.

The results exceeded an average forecast of 7.8 billion yen profit estimated by four analysts polled by Thomson Reuters I/B/E/S.

Shares of Toshiba, which competes with Hynix Semiconductor Inc in semiconductors and with GE and Areva in nuclear reactors, ended up 2.3 percent at 262 yen ahead of the results.

Tokyo's benchmark Nikkei closed up 0.69 percent.

($1 = 78.1900 Japanese yen)

(Reporting by Mari Saito; Editing by Richard Pullin and Michael Watson)