Updates with closing prices) BEIJING, Sept 13 (Reuters) - Chinese steel rebar futures were trading in a tight range on Monday but near high levels as peak seasonal demand and curtailed production at mills kept prices elevated, while prices for steelmaking ingredients slumped. Stockpiles of major steel products, including construction materials and coils used in the manufacturing sector, last week fell 2.8% to 10.71 million tonnes from the prior week, data from Mysteel consultancy showed. Meanwhile, weekly output of the metal stood at 10.15 million tonnes, as of Sept. 9, according to Mysteel, down 7% from same period a year earlier.“Affected by the coronavirus situation and floods in July and August, (construction) demand is likely to pick up during peak season,” analysts with CITIC Futures wrote in a note. The most-active rebar on the Shanghai Futures Exchange , for January delivery, edged 0.6% lower to 5,642 yuan ($874.40) per tonne at close. Hot-rolled coils futures, used in cars and home appliances, ended 1.7% lower at 5,805 yuan a tonne. Stainless steel on the Shanghai bourse, for October delivery, fell 2.3% to 19,180 yuan per tonne.Prices for steelmaking ingredients on the Dalian Commodity Exchange fell. Benchmark iron ore declined 3.5% to 706 yuan per tonne at close, while spot 62% iron ore was unchanged at $131.5 per tonne last Friday, according to SteelHome consultancy. Coking coal futures plunged 6.3% to 2,764 yuan per tonne and coke futures closed 7.3% lower at 3,397 yuan. Coking coal would be supported in the short term due to limited supplies as imports from Australia are still restricted, CITIC Futures said, adding that coke prices could be affected by cut in pig iron production.