Complete Text (Part 6)

of 6 is 25, of 6 is 36, ete, 16 square was 9,000,000. The given speed was 2,400, of which the square was 5,760,000. Therefore, according to the rule, we multiply 450 by 9,000,000 and divide by 5,760,000, which gives the re- quired result : 703 Ibs. We give below, in tabular form, the result of the ex- periments made in connection with this subject. This table will be of value to users of the centrifugal. In no case was the centrifugal to leave more than ).25 lbs. of butter fat in the skim milk (4 ounces). TABLE. 11. Pounds of milk skimmed per hour. et TET, ns iaann sehniauenenngeeeneinsneeenete | 981 Ibs. 489 Ibs. | 704 Ibs A TE AS CT SNORE | peace TEEND CASORERSE SN attieiinenetne smmummacnmeune | om Number of revolutions (ne-' Pounds of butter per 100 Ibs of milk Percentage of fat in | | skim milk 0.23 lbs.| 0.23 Ibs.) 0.22 lbs. | \ aeae ceemrerrenenn cence This table needs no comments. With an inflow of 281 Ibs. per hour, the machine required 1,954 revolutions a minute: when the inflow was increased to 489 lbs., it took 2.895 revolution to do the work, when the inflow rose to 704, 2,782 revolution were neeessary. U7 THE QUESTION OF SPEED IS OF GREAT IMPORTANCE. For example, with a milk flow of 435 Ibs. per hour, the small size Burmeinster & Wain’s separator left a minimum of 2 ounces of fat in the skim milk, but the quantity increased to 5} ounces, when the speed of the machine fell from 2,410 to 2,287 revolutions per minute, and to a maximum of 6} ounces, when the speed was still further reduced to 2,257 revolutions per minute. WHEN IS IT ADVISABLE TO BUY A CENTRIFUGAL MILK SEPARATOR, AND WHAT SIZE IS IT ADVISABLE TO BUY ? It is not, at present, advisable to buy a Centrifuga) Separator for a dairy of less than twenty cows SIZE ue The question of size depends on the quantity of milk to be skimmed and on the time which the dairyman can afford for this operation. In large public dairies the time allowed for skimming should not exceed from four to six hours. In private dairies the work should be finished in from one to three hours. it is desirable to have at least one large size Separates in every creamery of any importance. Prof. Fyord’s con- trol centrifugal for telling the amount of cream, in milk brought to the creamery, is adjustable to large Separa- tors only. No well managed public creamery can do without this instrument. Tavle showing the number and size of Separators ne- cessary to skim a given guantity of milk. 13 TABLE 12. Creameries receiving daily | Number and size of Separa- from tors necessary. 4to 5,000 lbs. of milk | 2 small Separators. 6to 8,000 “ ' i small and 1 large Separ rator. 9 to 12,000 “ i | 2 large Separators. 13 to 15,000 “ * io” e 16 to 20,000 “ co a The largest Separator will skim from 12 to 1600 Ibs per hour. The small Separator from 4 to 700 Ibs. Ifa small S-parator will do the work in a reasonable time get a smud one, If a large one will do, it is preferable not to try a large one, but rather to buy ¢éwo small ones. For if one gets out of order, the second can be made to do all the work while the first is being repaired. This rule does not apply to large establishments ; it is better to have two or three large Separators, than four or siz small ones. We give below our reasons. io. It takes less power to drive two large Separators than four small ones. 20. Four small Separators will require far more care in regulating the milk flow, than éwo large Separators. 80. Four small Separators will require far more care in regulating the speed, in looking after, in oiling, in cleaning, than two large Separators. 40. Four small Separators will cost more to buy, to set up, to keep in order, and to run than two large Sepa rators. 79 50. Four small Separators require more space than two large ones. ADVICE TO INTENDING- PURCHASERS OF THE CENTRIFUGAL Some one asks which Centrifugal to buy? We say buy a good one. POINTS OF A GOOD CENTRIFUGAL SEPARATOR. lo, A good Separator should be safe and strong, and its workmanship perfect 20. Its motion should be easy and steady. 30. The foundation should be solid, and the revol ving parts well protected. 40. It should require but a moderate degree of power in proportion to the work done. 50. It should be easy to take apart and to clean. There should be but few pieces to take apart. bo. Its construction should be simple and plain, and the manner of working readily understood. 70, It should be built so as to regulate the density ot cream (g ‘ting thinor thick cream), while in operation. 80. It should thoroughly skim the first and last milk contained in the drum. vo. The separated liquids should be discharged in good condition. 100. The mgchine should be cheap in the first cost, and cheap to put up. But the main point is that the machine be good, for a poor troublesome Separator, even cheap, will be more expensive in the long run, than a good one at a higher price. 8) DEFECTS TO BE GUARDED AGAINST IN CENTRIFUGAL SEPARATORS. lo. Liability to lose speed through any cause, shak ing for instance. (This is a very serious defect.) 20. Sprinkling of milk and cream, 80. Suction of cream by air into the skim milk. 40. Loss of oil and heating, through imperfect means of oiling the bearings. POWER REQUIRED TO RUN CENTRIFUGAL SEPARATORS. It is often supposed that centrifugal separators re- quire much power to ran them, This is a mistake. It takes less than three horse power to start the largest separators, Having reached full speed it requires much less power to keep it agoing. For this reason, several machines can be run by a power little greater than that which is necessary to start one or two large ones, Of course, in this case, the machines are not all started together. The first is set voing, and is got well under- way before the second is started; when these two have reached the highest speed a third is set going, etc, In dairies where two small sepa ratorg are used the dairyman should provide 8 or 4 horse power. This is more than the power absolutely necessary, but it is always wise to have some spare power. In large creameries from 6 to 10 horse power is required pices ay PRESSE. DIh peas NA kis otra ic ee te eprint ot co aa et SS Re q $1 REMARKS ON THE USE OF ANIMAL POWER IN RUNNING CENTRIFUGAL SEPARATORS In using a horse to run a separator, it is well to re- member that the strain on the animal depends : l.On the speed of the separator. For example a horse could easily run a churn containing from 60 to 80 Ibs. of cream and a small Burmeinster & Wain separator, at a speed of about 2200 revolutions per mi- nute, while the same horse would have all he could do to drive the same separator at a speed of 3000 revolu- tions per minute. 20. On the time required to perform the day’s work. Some farmers have milk for an hour daily. Others have milk enough for two or three hours, work. The less milk, the shorter is the time of the operation, and the more strain the horse could stand. 80. On the kind of horse-gear used. 40. On the speed at which the horse is made to go (1). In order to diminish the strain, use a larger pulley and decrease the speed of the horse, With a sweep power, the horse’s pace should be regulated so as to cover les Q than three feet of ground per second, Prof, Fjord’s experiments with the small separator of Burmeinster & Wain gave the following results : With 2000 revolutions a minute and to skim from 2 to 800 lbs. per hour it requires 4 horse power ; 1) [t must not be forgotten that the speed ofthe separator, and the speed of the horse are two dilferent things. The horse may be and should be (if the work is to last a long time) traveling very slowly, while the machine is working very rapidly h #2 o) With 2400 revolutions a minute and to skim from 3 to 400 lbs. per hour it requires # horse power , With 2800 revolutions a minute and to skim from 8 to 400 lbs, per hour it requires 1 horse power. THINGS TO BE REMEMBERED IN USING A MILK SHPARATOR. lo. Start the machine slowly, skim the first and last contents according to directiors given on page 28. 20. LET THE SPEED BE CONSTANT. For this purpose, every centrifugal milk separator should be provided with: lo A speed indicator attached to the spindle (1) so that the operator may ascertain the actual number of revolutions of the drum; 20 A belt strainer, to be used when the machine is losing sp:ed. 80. LET THE INFLOW BE CONSTANT. For this purpose geome means of controlling the inflow should be adopt- ed. Prof. Fjord’s controlling funnel is the best means we know of (see description, page 26). 40. WHEN THE SPEED DECREASES, DIMINISH THE IN- FLOW ; WHEN THE SPEED INCREASES INCREASE THE INFLOW. A decrease of 10 °/,, 20 °/,, 830°), in the given speed of the Burmeinster & Wain separator, must be at- tended by a decrease of 20 °),, 85 °7,, 50 974 in the milk inflow per hour. An increase of 10 °%,, 20°75, 80 %5 in the speed must also be followed by an increase of 20 °/,, 40 °),, 70 %/4 in the quantity of milk worked per hour, if the same amount of butter is expected from a given quantity of muck. (1) We say spindle and ast the main shaft, advisedly, because the revolutions of the latter do not represent accurately’ the revolutions of the drum, ¢3 So. SKIM THE MILK WHILE WARM. If this be inconve- nient, the miik van be warmed to 88° Fahrt. before skim- ming, 6o, FoR COLD MILK let the inflow be 4 less thar the inflow for warm milk. [If a machine skims 300 Ibs of hot milk in an hour, it will skim 200 lbs of cold milk in an equal time. Yo. KEEP WORKING PARTS VERY WELL OILED. Use for this purpose the best lard oil or neat’s foot. 80, CLEAN IMMEDIATELY after using. RELATIVE VALUE OF DIFFERENT CENTRI- FUGAL SEPARATORS. In determining the comparative value of rival Separa- tors, it is necessary lo. to determine what good skim- mine is; 20, to ascertain how large a quantity of milk each eparator can skim when leaving a given quantity of butter fat in the skim milk; 80. to see how long these can be run at their highest speed In Denmark the standard for average skimming by the Centrifugal is, to leave 0.15 of a pound o! butter fat in the skim milk. (This is equal to a trifle less than 24 ounces.) In Germany it is 0.35. (This is equal to a trifle more than 5} ounces.) We believe that between 0.20 and 0.25 is the proper standard-—-that is to say between 3 and 4 ounces. As some of our readers may think that there is not a great difference in the value of two machines, which. when skimming, the same quantity per hour leave, th one 24 ounces [.15] and the other 54 ounces [35] of but- ter fat in the skim milk, it is well to remark that in so1ae cases, if the inflow into the machine which is lea- old ving 24 ounces were increased so as to leave 54 ounces ; the inflow would be increased between 800 and, 400 Ibs. an hour. This is a very important consideration and should not be lost sight of in buying. We give below the result of a series of experiments made by Prof. J. N. Fjord to ascertain the exact capa- city of the four u «.ermentioned Separators in the fol- lowing circumstances, [The Burmeinster & Wain small and large sizes, the Neilsen & Petersen andthe De Laval Separato. 3.) lo. When each of the four Separators is extracting from the milk an equal quantity of cream of the same richness, [that is containing the same percentage of butter fat] and leaving the same quantity of fat in the skim milk. 20. When it is desired to leave a still larger propor- tion than 3 or 4 ounces of butter fat in a 100 lbs. of skim milk. On page 85 we give the result of these experiments in table No, 138. We see that du ‘¢ the period from April! to July, and for the smaliest quautity of milk worked per hour, the dif- ferences bet ween the “minimum” and the “ maximum”(1) quantities of butter fat, left in the skim milk, amount to 1, 4 ozs. and to 2, and 32 ozs. during the month of September. This comparatively small difference shows the uni- form reliability of the Centrifugal Milk Separator when properly used. (1) The figures in the column of averages are not obtained from the figures of the minimum and maximum only, but from a whole series af experiments. 85 rTABLE No iPercontage of butter P fat left in the skim TLL kK Note.—I'n order to avoid jJareg fractions, we have pretixed to the! number of ounces the sign minus. when the proper figure is a trifle} less than the given one. We have used the sign plus When the prope figure is a trifle more April and July 188%. A Burm. & Wain centrifuga 1, 290 ibs, of milk skimmed pert Aeeeee enenee 2. 435 lbs do do do B De Lavai’s centrifugal... 1. 300 Ibs. of mitk skimmed per| FOUL: sssoesste: seesecese ceases cegeee|, GOOU | 2. 450 ibs do do do | CO Nieisen & Petersen's centrifugal} 1, 49: ;bs. of milk skimmed per} hour TYITITIM TITEL os Coe covcer| 2, 810 lbs do do do | D Burmeinster & Wain’'s centrifu #ai (1AYZe BIZ)... | 1. 270 lbs, of milk skimmea per, hou eeVScarienKev dese dedekesaeebetel 2, 1280 Ibs do do do September 1882 a Burmeinsler & Wain’s separator (APNG BIAS): sacecsa: 40 c0ccceencces 1. 200 ibs. of milk skimmed per hour, 2. 435 Ibs. 3. 580 Ibs do 4. 720 lbs do do do b Burmeinster & Wain’s milk sepa-| rator (large size) Se re 1. 780 Lbs. of milk skimmed pe) BOUP ai voccee-dea sues 2. 1580 Ibs. 86 With a milk flow of 435 Ibs. per hour, the small size sSurmeinster & Wain Separator left a “ minimum ” of 2+ ozs, and a “maximum” of 6} ozs. of butter fat in the skim milk. With a milk flow of 1,280 lbs. per hour, the large size Burmeinster & Wain Separator, left a “ minimum” of 3, maximum ” of 6} ozs. of butter fat in the skim milk, sé ~ o48., and a With a milk flow of 1,580 Ibs. per hour, ‘he same size Separate: scft a minimum of 94, ozs. and a inaximum of v 12. oss of nuver fat in the skim milk. ‘Lo average of ‘he whole series of experiments in the Ist cuss Was 2} ounces ; In the 2nd 44 ounces, and in the 81d 11; ounces. From vie experiments made from April to July, the Separators :f classified according to efficiency, should be ou ~) found in the following order ; Taste No FOR THE SMALLEST QU: NTITY OF MIL? WORKED PER HOUR. iFract ofa lb lof butter “at! Heft in 100 ths.| In ounces lor skim milk, ' Nielsen & Petvrsen ......) 490 |lbs. per hour. 1} ozs, The small Barm. & Wain. 290 | « af 2 Almost 2 ozs « large < 870 eae B | 2 4/19 ozs, The De Laval | 300 Taare No, th. FOR THE LARGEST QUANTITY OF Nielsen & Petersen... 2 The small Burm. & Wain | ees ae The De Laval 810 Ibs. per lio Vontinued :— MILK WORKED PER HOUR, ee se ener er eres 0.18 2} ounces, (),22 34C« 0,27 Ay“ 0.31 Average 0,24 The average quantity of butter fat left in the skim milk amounts to 2,;% ozs. in the case of the first four Separators on the list, and to 8}} ozs. in the case of the Jast four. This last figure is nearly 75°, larger than the first. It is then safe to say, that an increase of 50°/, in the quantity of milk worked per hour, produces an increase of 75°;, in the amount of butter fat left in the skim milk, This increase amounts to about 13 ozs. of butter fat, and is equivalent to a decrease of 1, ozs. in the yield of butter per 100 lbs, of milk, that is if the smallest” quantity of milk worked per hour gives 4 lbs. of butter per 100 lbs. of milk, the “ largest ” quan- lity of milk worked per hour gives only 3.90 lbs. or 8 Ibs. 14 ounces, and instead of 25 Ibs. of milk to a lb. of butter, it would take 25%, or % of a lb. more, In a series of experiments made to test the relative value of the Nielsen & Petersen and Lefeldt Centrifugal, it was found, that a loss of butter fat amounting to 184 ounces took place for every hour the Lefeldt Cen- trifugal was worked. This loss was due to a certain