Factors affecting the rate of milk flow in pipeline milking machines

Abstract

A factorial experiment has been carried out to determine the effects of varying the level of vacuum, air admission, and reserve air on milking rate and the amount of strippings, in high pipeline, low pipeline, and large diameter low pipeline milking machines. The low pipeline and the large diameter low pipeline machines were found to milk 10.1 and 12.1 per cent faster, respectively, than the high pipeline machine. The large diameter low pipeline operating without air admission was 6.3-7.5 per cent faster than the low pipeline machine operating with and without air admission. Milking rate was 16.1 per cent faster at 15 than at 12 inches Hg vacuum and about 6 per cent faster at 17 and 5 cubic feet per minute (c.f.m.) reserve air than at no reserve air. The admission of air at the claw piece resulted in 9 per cent faster milking with the high pipeline and 9.5 per cent slower milking with the large diameter low pipeline machine. There was no difference in milking rate in the low pipeline machine with or without air admission. The fastest milking rate was observed with the large diameter low pipeline without air admission. However, this system probably has no real advantage over the low pipeline providing the diameter of milk pipe of the latter is sufficient to cope with high rates of milk flow.