The calculated values of the kinematic viscosity of 
distiiedswatemuagneed swith accepted values to within better 
than two parts per thousand. 
Bressurized System 
Figure 24 shows the essentials of the pressurized system. 
UNeeand) iB lare Whiteyearr operaced valves, “WA' being a 
normally shut valve which served to isolate the main part of 
the system inside the oil bath from the remainder outside at 
ambient temperature. Parts below the dotted line in the 
mioUneManre inside the oil (bath. ‘JA!’ prevented loss of liquid 
from the viscometer by condensation in the cooler outside line. 
"B" was a normally open valve and was used to raise the test 
iiquadvinto the, ,eftlux bulb to obtain.a.reading. This type 
of valve was chosen because it was capable of operating 
immersed in silicone oil at temperatures up to 150°C. 
Compressed air from a cylinder and two solenoid valves were 
WSCCmntOwoOpera te | VANsrand) 1B I". 
On the right in the diagram the system ended in a 
closed chamber consisting of a 1'' diameter hole drilled in 
I MeCUDeMOL stainless steel.) It had provision for a 
pressure transducer and was closed at the far end by a 2"- 
diameter plate and o-ring. All connections were done with 
1/4" stainless steel tube and Swagelok fittings except for 
the tubes immediately connected to the viscometer. These 
were of 1/8" tubeto provide some flexibility since the 
connections to the viscometey had to be bent until they 
flected wathout puttingsany strain on the glass. 
While the bath temperature was being altered or while 
waiting for the bath temperature to become steady, "A'' was 
closed Ub awassopenjand the ites t Jiquid was in the receiv- 
INP eDULD ee lOmtake a Geading jy) A" was opened, "B" closed, 
and compressed air from a cylinder used to push the liquid 
inGOmenesetilux bulb. Once the liquid reached the £111 mark, 
the pressure in both arms was equalized by opening "B", ''A" 
was closed and the liquid allowed to run back into the 
receiving bulb. It was estimated that there was ample time 
for the pressure in both arms to equalize before the 
meniscus reached the first timing mark, ''C". 
ihe pellosed chamber onthe right provided some buffer 
volume to prevent the pressure in the efflux arm from 
becoming too great as the liquid was raised. For readings 
up to 80°C, where evaporation was less severe, the pressure 
in the system was released after each reading by opening "A" 
TS 
