THE STORAGE OF GAS
629
being rounded, the usual 50 per cent, reduction may be assumed—thus giving an effective pressure of 16 Ib. per square foot on the diametrical projection. Primarily
Fig. 382.—Radial Roller and Cakriage, showino Mbthod or Adjttstment.
it must be understood that the wind and snow pressure is received by the holder
beil, and, by means of the guide rollers, it is transmitted to the upright standards, which. are braced together in such a manner as to withstand distortion and any tendency to capsize. The maimer in which the stresses are transmitted to the framing is chiefly dependent upon the system of guide rollers adopted; i.e. whether the rollers are radial, tangential, ot a combination of both. The ordinary radial roller is shown in Fig. 380.
Fig. 381 shows a combination of the radial and tangential methods.
The arrangement of guide rollers adopted on the large holder at East Greenwich is shown in Fig. 384.
AVith the 10 million. Cllbic feet Kt<;. 383.—Combined Radial and Tangential Guide holder at Manchester the design. Rollebs and Cabbiages for 3-Lift Gasholdeb.
shown in Fig. 385 was employed.
For the purposes of calculation, the whole of the guide-framing may be regarded as an immense cylinder, receiving partial stiffening from a light internal ring (the beil itself). If we consider a simple holder with radial guide rollers subjected to