Boekel Scientific 25515016 Cement Autoclave - Manual (Page 4)

2.2.2 Differential
The “differential” adjustment screw should be turned clockwise as far as possible to
reduce the differential between “make” and “break” to a minimum for close control during
the constant pressure period. This screw has been factory set to the minimum position.
2.3 Safety Valve
The safety valve is mounted on the bolted cover of the autoclave. It has tested and set to
release at 350 PSIG. It complies with Section I of the A.S.M.E. Boiler and Pressure
Vessel Code. The manufacturer guarantees that this valve has a capacity to release at
least 1000 lbs. of steam per hour. Since the autoclave contains only enough water to
generate about 1.3 lbs. of steam, this valve has many times the capacity required in
autoclave operations. Modification or repair of the valve from an unauthorized service
provider is strictly prohibited and will automatically nullify the product warranty.
2.4 Cylinder and Cylinder Head
The welded steel cylinder and the cylinder head have been designed and tested to
withstand a pressure of 525 PSIG. This translates into a maximum allowable working
pressure of 350 PSIG.
2.5 Vent Valve
The vent valve is a needle valve located in the piping system which links up to the
cylinder, pressure gage and the regulator.
2.6 Gaskets
The high temperature gaskets furnished with the autoclave have been found to give more
service, satisfactorily and at a lower cost, than the many types of special gaskets
available on the market.
3. Specifications
For cement soundness tests, the autoclave will accommodate either a Specimen Holder
for 8 test bars of 10-inch effective gage length or a Specimen Holder for 16 test bars of 5-
inch effective gage length. The automatic pressure regulator is set for this purpose to
maintain a steam pressure of 295 ± 10 PSIG which corresponds to a temperature of 420°
± 3° F. A maximum of 75 minutes is required to heat the autoclave to this temperature.
When the current to the heaters is cut off and the cover is removed, cooling to a steam
pressure of 10 PSIG within one and one half hour interval is accomplished by adjustment
of the draft control lever.
Boekel Model Number 25515016
Operating Pressure Range, PSIG 60-350
Operating Voltage, Volts 115
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