MACHINE SEPARATION

New Zealand Herald, Volume LXXI, Issue 21875, 10 August 1934, Page 3

MACHINE SEPARATION

AVOIDING VIBRATION ! FAULTS TO LOOK FOR NEED OF STERILISATION BY FAN No. 11. Faulty running of the separator due to excessive vibration must be rectified without delay. A spirit level should be available in every milking shed and should bo used at intervals to make sure the separator is standing level while separation of the milk is taking place. The driving belt should be on the pulleys and all conditions should be the same as when the machine is running. Remove the cream and skim milk covers, also the bowl, and place the spirit level across the machined edges of the frame. Try the level in two directions at right angles to each other, loosening the holding-down bolts and inserting strips of plain galvanised iron until the separator frame stands perfectly level- Tighten up the holdingdown bolts as before and do not neglect to verify the level of the separator from time to time.

A worn bowl spindle can be detected by removing it from the frame and drawing it gently between the thumb and first finger. If worn at the bearing part a distinct ridge will be felt, indicating the amount of wear which has taken place. To test the lower bushing for wear, remove the top, or neck-bearing, and note how far the spindle will lean from the perpendicular in any direction. The amount of this movement should not be very great. It it is necessary to remove the lower bushing—assuming the proper tools are not available— it is best to lay the frame over on its side and drive the bushing upward. For this purpose a short piece of round iron may be used, but for putting the new bushing into position a hard wood spoke from an old buggy wheel is best, as it will not injure the new bearing. Attention to Steel Points

It may be noted, in passing, that the horizontal bushes of the driving shafts are also tapered and may be driven out in like manner, usually toward the large driving wheel.

The steel points upon which the bowl spindle revolves should be examined occasionally and the points replaced when worn or chipped. The one in the lower bushing is easily driven out with a stout nail, through the opening provided. To remove the steel point in the bowl spindle is a more difficult) operation. A simple and effective method is to heat the end of the spindle in the flame of a spirit lamp or similar jet, when on cooling in water it usually drops out, op can be easily removed with, a pair of pliers. Do not heat the spindle end to more than a dull red, and when cool brighten it with oil and sand-soap, wood ashes, or other mild abrasive.

If the bowl is out of balance owing to the discs not fitting it tightly the remedy is obvious, and in extreme cases two or three more discs are required. Should the cream run thick and thin, the bowl vibrate while running, or a rattle inside be heard when the bowl is shaken before being placed in the frame, it is fairly certain more discs are needed; always keep the bowl full of discs.

Badly-worn discs or mechanical injury to the bowl structure is a more serious matter, as the howl and discs have to be sent to the shop for repairs and re-balancing. Fortunately, a bowl can be supplied on loan while this is being done so the separating operations are not interrupted. Another Cause of Vibration

There is another rather common cause of bowl vibration about which little is said or written. It results from insufficient time being allowed for the bowl to attain full speed when starting up the separator In addition to imposing a severe strain upon the brass worm wheel and bowl spindle, it causes the bowl to vibrate for the following reasons:—When a body is rotated upon its axis it generates two forces known respectively as centrifugal (centre fleeing) and centripetal (centre seeking). Given time to adjust themselves, one to the other, these forces will harmonise and a sweetly-running bowl results. Should the starting be hurried this happy combination is not obtained and vibration is set up, which usually continues through the entire run. A farm cream separator requires at least five minutes to gain full speed when started up.

During the vogue of the creamery system one manager of a skimming station was well known for the sweetrunning of his power separators. This was largely due to his practice of starting them slowly before the suppliers arrived and they usually had 15 minutes or so in which to gather full speed. Under ordinary conditions the effective life of a power separator was considered to be five years. In the case mentioned they ran for seven years with good rtesults. With careful treatment the life of the separator on the farm can also be extended for several additional years Cleansing and Sterilising

Separator hygiene must be given strict attention. For some unknown reason the necessity for cleansing and sterilising the cream separator has not been emphasised to the same oxtent as when dealing with the milking machine. As n chajn is only as strong as its weakest link, so the hygienic condition of a milking plant must be judged by its least sanitary unitIt is necessary for the- separator to receive the same sterilising treatment as the milking machine for the need of this is the same in both cases. The practice of washing the separator parts in water which is not too hot for the hands and then placing the parts on a bench to dry is not an effective way to treat them. Provisions should be made for immersion in scalding water after they have been washed