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THE INDIA RUBBER WORLD 



IlNE 1, 1921 



Rubber Mill and Calender Lubrication 



THE power transmissions and heavy machinery employed in 

 modern rubber factories for washing, mixing, warming and 

 calendering require careful selection of suitable lubricants, 

 because of the excessive weight of the moving parts and the severe 

 load conditions. 



KeysTvnc Lubricating Co. 



Mill Equipped with Spring Grease Cups on Roll Bearings 



Before the introduction of the present heavy types of mills and 

 calenders the use of oils for lubrication was the general practice. 

 It is doubtful if this was ever good practice, even on the relatively 

 small mills and calenders of years ago ; certainly, it cannot be 

 rated as good practice today, because practically all oils and most 

 greases thin down so readily under present working conditions of 

 speed and pressure that without constant attention and frequent 

 renewal of lubricant excessive frictional heat will develop, with 

 danger of fire and injury to the machinery. 

 BEARINGS 



Bearing troubles come from many causes. Among these are : 

 poor alincment, improper grooving, inefficient lubrication, too great 

 pressure per square mch of bearirtg area, inferior bearing metal. 



scored bearings, etc. The elimination of this list of mechanical 

 defects must precede efficient lubrication, which will then depend 

 on proper choice of the luliricant to meet the conditions of speed 

 and pressure. 



VALUE OF THE LUBRICANT 



The value of a lubricant lies not only in its capacity for reducing 

 the frictional load under moderate bearing pressure, but also in 

 developing a low coefficient of friction under severe loads. Such 

 lubricants have been developed for heavy machinery of every type, 

 in the form of special greases, applied by means of suitable feed- 

 ing cups. 



GREASES 



Originally, the ordinary lubrication greases were little more than 

 soft soap containing a filler such as wax, paraffine, rosin, rosin oil. 

 talc, clay, graphite, etc., having little or no lubricating quality. 

 Many greases are made wholly or in part from animal fats wliich 

 may become rancid and very oflfensive. Such greases are usually 

 highly scented with oil of myrbane, which smells lil<e almond oil, 

 to disguise the odor arising from this cause. Pine petroleum 

 grease and other semi-solid lubricants have been found by test to 



Keystone I.ubricatins Co. 



RtreBER Mill Showing Gravity Cups and Hand Compression 

 Grea.se Cups 



. / :(.''n\-ti.'ij:,f Co 



Rubber Calender Eouipped with Gravity Grease Curs 



possess the greatest relative capacity and lubricating efficiency 

 under various bearing pressures. 



RUBBER MILL APPLICATIONS 



Driving gears and reduction gears require a grease not too light 

 in density that will not be thrown off by centrifugal force at the 

 operating speed. Such greases will possess unusually tenacious 

 hibricating properties and maintain their original densities under 

 the severest operating conditions. 



Cleanliness is a vital feature in the lubrication of rubber mill 

 machinery, as misplaced lubricant frequently comes into contact 

 with the rubber, resulting in injury and loss. Trouble of this sort 

 may be overcome by the use of specially designed cups feeding by 

 gravity or pressure according to the density of the grease used. 



In the case of ordinary rubber mills grease pockets are sometimes 

 used in place of automatic spring cups. In order to secure ade- 

 quate and efficient distribution of grease over the contact surfaces 

 of bearings it is vitally important that attention be given to the 

 grooving of the bearings. 



The illustrations show the application of both gravity and pres- 

 sure types of grease cups to rubber mills and calenders, which 

 today has practically become standard practice. 



