Reynolds 853 - heat treated
UTS: 81 - 91 Tsi, 180 - 210 Ksi,
1250 - 1450 MPa
This tube, when introduced in 1995, set new standards for professional cycle frames. It is suitable for TIG welding and brazing, using lugged or lugless construction. The production process ensures tight tolerance, gauge tubes. The strength to weight ratio of 853 is equal to that of quality titanium frames. A normal chrome molybdenum steel will lose strength in the joints after the heat has been applied. This material (853) INCREASES in strength as the frame cools to strengths well in excess of the delivered values shownabove. This unique air hardening property of Reynolds 853 providesadditional stiffness through reduced microyielding at the joints, allowing stiffer frames with excellent fatigue strength (when compared to standard chrome molybdenum) and excellend ride quality to be constructed. On road and touring frames we recommend the use of 531 fork blades with 853 frames.
Reynolds 631 - cold drawn
UTS: 52 - 58 Tsi, 115 - 130 Ksi,
800 - 900 MPa
Following on from the success of 853, Reynolds have added 631 to the range of AIR HARDENING STEEL tube sets. This cold drwan steel tube will allow the benefits of this new steel to be used in the manufacture of a wide range of frames. Like 853 it is suitable for TIG welding and brazing, with lugged or lugless construction, and in the heat affected joint areas will gain strength, to tensiles in excess of heat treaded chrome molbdenum. The strength to weight ratio of 631 is equal to that of many aluminium frames, and it has an excellent fatigue life, when compared to standard chrome molbdenum frames. On road and touring frames we suggest 531 forks be used in conjunction with 631 frames. As 631 is only available in main frame tube sizes, we recommend the use of either heat treated CrMo (725) or cold drawn CrMo (525) seatstays and chainstays to complete the frame.
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