Neway Valve (Suzhou) Co Ltd, a major industrial valve manufacturer in China, went on board on Friday with a strong debut as investors cheered China's first initial public offering (IPO) after a year-long freeze.

Its stock on the Shanghai Stock Exchange opened around 20 percent higher over the offering price and continued to head upward by up to 31.99 percent, prompting regulators to temporarily [Company Formation | Offshore Company | Company Incorporation]halt trading according to new IPO rules that mandated a required price range.

The strong comeback came after China announced to resume IPO approval at the end of last year after it froze the process in 2012 amid fears that new shares would undermine confidence in the already dismal market, along with a new reform plan that changes the system from approval-based to registration-based.

But earlier this month, the China Securities Regulatory Commission (CSRC) stepped in to introduce new measures to tighten the supervision of IPO, two days after Jiangsu Aosaikang Pharmaceutical Co Ltd shelved its share sale plan, saying "the proposed issuance was too big."

The maker of anti-cancer agents had planned to debut on the ChiNext board by selling 55.46 million shares priced at 72.99 yuan ($11.97) each, which could raise a capital of 790 million yuan from the IPO. [Company Incorporation USA]The price-to-earning (PE) ratio is 67 times its 2012 net profit, setting a new record of PE ratio since the restart of China's IPO at the end of 2013.

The CSRC required issuers and underwriters to publish timely investment risk reports at least once a week during the three weeks prior to online subscription, if the PE ratio manifested in the proposed IPO price is higher than that of their listed peers.

The financial watchdog said it would conduct spot checks on the IPO roadshows and halt a company's IPO and mete out punishment if its issuers and underwriters used information other than what is disclosed publicly in its prospectus.