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A four-vane radio-frequency quadrupole (RFQ) accelerator is under construction for the Compact Pulsed Hadron Source (CPHS) project at Tsinghua University.The 3 m-long RFQ will accelerate a 50 keV proton beam from the ECR source to 3 MeV,and deliver it to the downstream drift tube linac (DTL) with a peak current of 50mA,pulse length of 0.5ms and beam duty factor of 2.5％.The inter-vane voltage is designed to increase with the longitudinal position to produce a short RFQ.Coupling plates are therefore not necessary.The cavity cross section and vane-tip geometry are tailored as a function of the longitudinal position,while limiting the peak surface electric field to 1.8 Kilpatrick.The RFQ is designed,manufactured,and installed at Tsinghua University.We also present the tuning and cold test results of the RFQ accelerator.After final tuning,the relative error of the quadrupole field is within 2％,and the admixture of the two dipole modes are less than 2％ of the quadrupole mode.