Double-loop check pressure retaining valve

The utility model provides a double-loop check pressure retaining valve. The utility model discloses a pressure retaining valve, and relates to the technical field of pressure retaining valves. The pressure retaining valve comprises a first pressure retaining guide cylinder, a second pressure retaining guide cylinder, a first check seat arranged below the first pressure retaining guide cylinder, asecond check seat arranged above the second pressure retaining guide cylinder, and a spring arranged between the first check seat and the second check seat. According to the utility model, a double-loop non-return mode of the oil inlet and the oil return port is adopted; when the oil pressure reaches the working pressure, the first pressure maintaining guide cylinder and the second pressure maintaining guide cylinder can be closed in an inserted mode, and the problem that when existing hydraulic oil contains tiny dirt, the contact face of the check steel ball and the pressure maintaining guide cylinder falls off, a g