This invention relates to a standard device for extending the liquid circuit for easy extravehicular operation by astronauts, comprising an extension adapter and an extension housing. The extension adapter is the passive end, installed on the
spacecraft cabin and launched with the
spacecraft. The extension housing is the active end, installed by the astronaut after exiting the
spacecraft and attached to the extension adapter. The extension adapter and the extension housing are connected mechanically, electrically, and through liquid circuits. These interfaces are all standard interfaces, and the connection method is independent of the type of liquid circuit equipment installed inside the extension housing, such as pump assemblies, valve assemblies, and
working fluid replenishment assemblies. The standard device for extending the liquid circuit of this invention features standardized
interface design, adaptability for astronauts operating while wearing extravehicular spacesuits, no need for auxiliary tools, simple operation, and short
operation time, and can meet the requirements for pressurized, leak-free operation of the extravehicular liquid circuit.