Ryoden International (Hong Kong) Co., Ltd. is one of the large group companies established in the 1960s. It was initially jointly operated by a Hong Kong-foreign joint venture and a holding company. In its early days, its main business was Acting as an agent for foreign audio-visual and air-conditioning terminal products, after years of development, it has gradually become involved in real estate investment, elevator manufacturing and other industrial industries.

In the late 1980s, Ryoden International invested in the first independent brand cooling tower production factory in Shenzhen. In 1992, it moved to Dongguan City, known as the world's manufacturing factory. The cooling tower production base was built in Huangjiang Town. In 2005, one of the largest cooling tower brands in China declared bankruptcy due to the decision-making and operational errors of shareholders of Dongguan Lingden Factory.

This incident had a very negative impact on Hong Kong Ryoden. Ryoden International (Hong Kong) Co., Ltd. decided to take back the right to use the cooling tower trademark. In 2005, the domestic office signed many supply contracts with agents. It has not yet been completed, so Lingdian International signed purchase, sale and production contracts with several outstanding domestic cooling tower manufacturers, including Dongguan Lingke Cooling Equipment Co., Ltd., the predecessor of Feiyang Group.