Yamazaki, H. Ikeya, Y. Kishimoto, H. Matsuzaki, Y. Miura, T. Ohashi, H. Senba, Y. Shimizu, Y. Takeuchi, T. Tanaka, M. Tsuboki, I. JACoW Publishing Geneva, Switzerland In SPring-8, 21 of the 28 X-ray undulator beamlines have the same sets of a double-crystal monochromator (DCM) and a cryogenically cooling system. A remaining problem is vibration for the forthcoming upgraded SPring-8. For certain experiments, vibration seems to fluctuate the source position. The virtual fluctuation, which increases the effective source size, degrades high-density nanobeam made by direct projection of the source. When a DCM is placed at 40 m downstream from a source with 6-um size, the vibration should be 50 nrad to suppress 20%-increase of the source size. The vibration was over 800 nrad in 2011. We have continued improving low-vibration flexible tubes for transport tube of liquid nitrogen, high-rigidity tilt stages, and temperature controllers of the coolant. The latest-version refinements were carried out to 5 DCMs in 2017FY. The vibrations were reduced to about 110 nrad in 4 DCMs and 55 nrad for one.