GB1386405A - Pipe supports - Google Patents

Abstract

1386405 Constant-tension spring units PIPE SUPPORTS Ltd 20 March 1972 [13 March 1971] 6822/71 Heading F2S A pipe 1 (such as a steam pipe in an electricity generating station) is connected for support, by means such as a pin 15 mounting an eye bolt 16, to a lever 10 pivoted at 11 on a frame 12, there being spring means (not shown) acting between the frame and lever; the support has either means for adjusting the distance between the position where the spring means acts on the lever and the pivot 11 or else means for adjusting the distance D between the position where the load-carrying means 15 acts on the lever and the pivot 11, the adjusting means including co-operating components on the lever 10 and frame 12 to decrease from an initial value the distance of the spring means or such adjusting means to increase from an initial value D1 the distance D1 of the load-carrying means 15, during movement of the lever from a first position corresponding to a cold supported pipe to a second position corresponding to a hot supported pipe (containing steam) and to prevent subsequent return of the particular distance to its initial value during at least a major part of the travel of the lever from its second to its first position. The spring means and the load may act on a single arm lever but as shown there is a separate load-attaching arm, shown in the position 38 in which the supported pipe is full of cold water. As the water and pipe become better, the pipe moves downwardly and the lever 10 pivots anticlockwise about the pin 11. The loadsupporting pin 15 is supported at its ends in slots 14 in a pair of parallel plates 13 which constitute the lever 10. The load-attaching arm is at a position 20 when there is saturated steam in the pipe and the major axes of the slots 14 are horizontal. Further pivoting of the arm causes downward inclination of the slots so that the pin 15 moves in a direction away from the pivot pin 11 to a distance D2. To maintain the distance D2 as the pipe re-cools and rises and the load arm consequently rises, i.e. to restrain movement of the pin 15 back along the slots 14 towards the pivot pin 11, there is a pair of arms 24 pivoted on the respective lever plates 13 at 25 and each receives one end of the pin 15 in an aperture 26. Each of the apertures 26 is oval with its major axis transverse to that of the adjacent slot 14. At its free end, each arm 24 bears a cam follower 27 for coaction with a cam 28 projecting from the inner face of a respective side plate 12 of the frame which bears the pivot pin 11. Arrows 32 indicate the paths of the followers 27 around faces 29, 30 of the cams 28. To ensure the movement of pin 15 away from pin 11 as the lever pivots beyond the position indicated by line 20 there may be another cam 31 for coaction with the follower 27 of each arm 24. This cam also prevents the pin 15 digging into the surfaces of the slots 14 although this may be prevented by yet further cams and followers.