Castrol, Hero Honda, Idea Cellular and Kotak Bank are scheduled to announce their June quarter results today.Balrampur Chini, Bharat Forge, Britannia, Elder Pharma, GTC Industries, GTL, Hindustan Zinc, Ispat Industries, JSW Steel, Mahindra Gesco, MindTree, Pidilite and Varun Shipping also to announce earnings today.