From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test report on the graduation and accuracy of a Nivex petrol gauge on a 23EX petrol tank.
| Identifier | ExFiles\Box 61\3\ scan0015 | |
| Date | 19th March 1930 | |
| Copy for files Y4523. NIVEX PETROL GAUGE GRADUATION 23EX PETROL TANK USED FOR TESTS. THE CALIBRATION WAS FIRST MADE BY MARKING ON THE PAPER FIXED ON THE GAUGE GLASS THE POSITION OF THE FINGER FOR EACH GALLON (BY MEASURE) PUT INTO THE TANK. THE GAUGE THEN BEING RETURNED TO THE MANUFACTURER'S FOR MARKING. WHEN RETURNED TO US, THE GAUGE WAS AGAIN FITTED TO 23EX. TANK. AND CHECKED OVER, USING THE "BOWSER" PUMP. WE FOUND THAT THE GAUGE REGISTERED 1/2 GALLON MORE THAN THE PUMP (e.g. P10. G10.5; P15. G15.5). BY ADJUSTING THE DEPTH OF THE TUBE IN THE TANK WE WERE ABLE TO CORRECT THIS ERROR, AND A REPEAT TEST SHOWED ALL O.K. IT WAS NOTICED THAT WHEN FILLING UP, THE GAUGE REGISTERED 1/4 - 1/2 GALLON LESS THAN THE PUMP, BUT APPLICATION OF THE SMALL HAND PUMP PROVIDED WITH THE GAUGE CORRECTED THIS. THE TANK WAS THEN EMPTIED GALLON BY GALLON - BY MEASURE - AND READINGS TAKEN BEFORE AND AFTER USING THE HAND PUMP. DURING THIS PROCESS THE GAUGE READ ALWAYS LESS THAN THE ACTUAL QUANTITY IN THE TANK - APPROX 1 GALLON - BUT THE HAND PUMP WAS ALWAYS EFFECTIVE IN CORRECTING BUT NEVER EXCEEDING THE DEFICIENCY. WHEN TAKING OUT THE LAST "GALLON" WE WERE JUST 1 PINT SHORT, THERE WAS NOT APPARENTLY THIS AMOUNT LEFT IN THE TANK, SO THAT THIS LOSS MUST BE DUE TO EVAPORATION AND ACCUMULATED INACCURACIES DURING MEASUREMENT. THE LOW READING EFFECT WHEN EMPTYING SEEMED TO BE DEPENDENT UPON THE TIME BETWEEN THE READINGS, THIS BEING NOTICED PARTICULARLY WHEN, AFTER FILLING, WE PREPARED FOR EMPTYING. WE THEREFORE LEFT 4 GALLONS IN THE TANK OVERNIGHT WITH THE GAUGE READING 4 GALLONS. NEXT MORNING THE GAUGE WAS AT ZERO, BUT A FEW STROKES OF THE HAND PUMP BROUGHT THE GAUGE BACK TO 4 GALLONS. THE HAND PUMP SOMETIMES SPRINGS BACK ON ITS OWN, AND SOMETIMES REQUIRES A SLIGHT EFFORT ON THE RETURN STROKE. 1.17 (P.T.O) | ||