Small grooves 22 and 23 respectively are formed in the inner surface of the disc 20, and {HEAD ~ small grooves} 24 and 25 are formed in the outer surface of {TAIL ~ the flange} 19 and the lower surface of the thrust support 21, respectively 
Small grooves 22 and 23 respectively are formed in the inner surface of the disc 20 , and { HEAD ~ small grooves } 24 and 25 are formed in the outer surface of { TAIL ~ the flange } 19 and the lower surface of the thrust support 21 , respectively
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH