Abstract: In recent years, high-precision mass measurements of short-lived nuclides were conducted using isochronous mass spectrometry (IMS) based on the Cooler Storage Ring at the Heavy Ion Research Facility in Lanzhou (HIRFL-CSR). The new data enable us to discuss some related physical problems in the realm of nuclear structure and astrophysics. In this contribution, details of the measurements and data analysis are described. The IMS with two Time-Of-Flight (TOF) detectors is mainly introduced. In order to improve the mass resolving power while preserving the acceptance of the storage ring, additional velocity information beside the revolution time in the ring is obtained for each of the stored ions by using the double TOF detector system. The IMS with two TOF detectors is a brand new concept, and relevant experimental techniques need to be developed. We have established a simulation platform based on CSRe, developed high-performance TOF detectors and installed them in a straight section of the CSRe, performed online beam testing, developed new ion optics and optimized them, and developed data analysis methods and optimized them. Furthermore, planned technical developments are outlined in this contribution.