WING Hang Bank and Chase Manhattan are expected to tap the market for $1 billion. These issues, along with three of the nine mainland enterprises that will hit the market over the next six weeks, have sparked concerns that the liquidity now driving the Hang Seng Index could be affected. Wing Hang plans to raise about $600 million through an initial public offering and will start trading in early July. Brokers said Wing Hang would issue 36.8 million shares at $16 to $17 each, with a price-earnings ratio of 11 to 12 times. This would represent about 15 per cent of total equity and give Wing Hang a market capitalisation of $4 billion. ''It is about time Wing Hang came to the market,'' said a broker close to the deal. ''It is a well-established bank and I think it will be well-received.'' Brokers said Chase Manhattan Bank would soon announce plans to raise $400 million by spinning off its credit-card division, which would be called Card Manhattan. Earlier reports suggested a 25 per cent stake would be sold to the public with Chase Manhattan and a mainland-related company holding the remaining shares. Like Wing Hang's, the new issue will sport an 11 to 12 times PE and will probably be heavily oversubscribed. Last year, Chase's credit card division saw profits jump 75 per cent to $14 million. The Bank of New York and the Fung family, which hold 49 and 51 per cent stakes respectively in Wing Hang Bank, will see their holdings diluted to 37 and 48 per cent. Schroder Securities, the lead underwriter, will hold a presentation today for analysts to discuss the listing and how proceeds will be used. Wing Hang's issue will be the largest bank listing since Hongkong Chinese Bank raised $400 million last October by listing a 24 per cent stake. Investors' enthusiasm for the stock saw oversubscription of 48.29 times. Barclays de Zoete Wedd banking analyst Herbert Hui said Wing Hang Bank had chosen an ideal time to raise funds because of the robust market conditions and investor willingness to pay a premium for bank stocks. He said many banks were looking to issue shares to raise much-needed capital due to the slowdown in deposit growth, which is expected to dip below 10 per cent this year. Sun Hung Kai Securities research director Percy Au-young added that despite many stocks having consolidated recently, he expected there to be keen interest in the Wing Hang issue. He said investor interest in bank stocks was underlined when rumours of HSBC Holdings spinning off its Hongkong Bank unit sent HSBC shares climbing. Brokers said the banking sector had been sluggish recently as investors waited for Wing Hang to announce its listing plans. Wing Hang, one of Hongkong's oldest private banks, first disclosed last month that it was contemplating a listing. The bank has 20 branches in Hongkong and Macau with plans to upgrade its representative office in Shenzhen to branch status by the end of the year. The bank has China exposure through loans to entrepreneurs who have expanded into Guangdong. Over the past five years, Wing Hang has grown dramatically. Compound earnings were up 35.5 per cent from 1988 while deposits climbed 21.5 per cent, loans 25.2 per cent and assets 21.6 per cent. The bank posted net profits of $271 million for the year ended December 31, 1992, compared with $203 million a year earlier. With total assets of $18.08 billion, Wing Hang is the 10th largest bank in the territory.