X-ray lasers are an important area in the fields of laser and plasma physics. At present, the studies of X-ray lasers focus mostly on Z-pinch carbon discharge and the short and multiple laser pulse from high power lasers, and most of which confine in Soft X-ray laser. Inspired by the device of free-electron lasers, a newly designed device of X-ray laser is put forward. This device is converting free electron laser tool into free electron pumped laser tool through replacing wiggler by capillary hollow tungsten electrode which is full of specially metal steam such as copper steam. Its working principle and feasibility are analysed and proved by many theory such as electron impact ionization, equilibria system of high-energy particle beams and recombination properties of plasma produced.