In 1936, she was assigned to transport $50 million (1936 prices) worth of Chinese artwork from London to Shanghai. The art had been on display in England as part of the largest exhibit of Chinese art to appear in England to that point. On 14 April, she encountered a storm off Gibraltar and ran aground in the Punta Mala after dragging anchor.[2] She was refloated without damage on 16 April and resumed her trip to China.[3]
Her sister ships SS Rawalpindi, SS Ranchi and SS Rajputana were also converted to armed merchant cruisers. Except for small corvettes, the converted passenger ships like HMS Ranpura were the only armed protection for most of the early convoys. With their six-inch (152 mm) guns, they were the only escorts that could engage German surface ships. After conversion, Ranpura was assigned to the Mediterranean, where she served until February 1940, when she was transferred to the South Atlantic.[4] She served with the Halifax Escort Force in May 1940, then was assigned in March 1941 as part of the force transferring gold from Britain to Canada for safekeeping during the war. After October 1941, she transferred to the Indian Ocean.[4]