* GRAPHIC-2019 asset returns: (Adds aluminium spreads, updates prices)By Eric OnstadLONDON, July 31 (Reuters) - Lead touched a two-week low onWednesday after inventories piled up and a major refineryassured consumers that a maintenance stoppage would not resultin shortages.Markets were on edge ahead of a second set of Chinesefactory data due on Thursday and an expected U.S. interest ratecut later on Wednesday.The lead market surged 14% over three weeks earlier thismonth before hitting a four-month peak on July 25, reflectingsmelter closures and as London Metal Exchange-registered stockshit decade-long lows.But the situation has reversed in recent days as signsemerged that supply was healthy, sending prices lower."All the signals are pointing to better supply on themarket," said analyst Daniel Briesemann at Commerzbank inFrankfurt, pointing out that the Port Pirie smelter hadrestarted, resolving a major outage. "The price rise was somewhat excessive, partly driven byspeculation, so lead was ripe for a correction."
LME benchmark lead hit an intraday low of $1,981.50,the weakest since July 17, before recovering to rise 0.4% to$2,005 a tonne by 1410 GMT.
* LEAD STOCKS: Lead inventories in LME-registered warehouses surged by 11,725 tonnes to 79,050 tonnes, dailydata showed on Wednesday, bringing the two-day rise to 42%.
* LEAD: Korea Zinc had secured inventories aheadof refinery maintenance being carried out until late August, sosupplies will not be interrupted, a spokesman said.
* TRADE TALKS: U.S. and Chinese negotiators wrapped up abrief round of trade talks on Wednesday, that Beijing describedas "constructive", including discussion of further purchases ofAmerican farm goods and an agreement to reconvene in September.
* CHINA PMI: China's factory activity shrank for the thirdstraight month in July, with the official Purchasing Managers'Index (PMI) at 49.7 in July, slightly firmer than June's 49.4and higher than expectations.
* "This shows that stimulus measures announced previouslyare having some positive impact on the manufacturing sector,"said analyst Helen Lau of Argonaut Securities.
* FED: The U.S. Federal Reserve is almost certain to cutinterest rates for the first time in more than a decade onWednesday.
* ALUMINIUM TIME SPREADS: The discount of cash aluminium tothe three contract has sunk to $29.75 a tonne, thelowest since June 17 and compared to a discount of $14 threeweeks ago, indicating healthier near-term supply.
* PRICES: LME three-month copper fell 0.2% to$5,934.50 a tonne, aluminium slipped 0.1% to $1,801,zinc dropped 1.3% to $2,427.50, nickel edged up0.03% to $14,365 and tin shed 0.2% to $17,420.
* For the top stories in metals and other news, click or (Additional reporting by Mai Nguyen in Singapore Editing byDavid Holmes and David Evans)
Reuters Messaging: eric.onstad.thomsonreuters.com@reuters.net))