manufacturer:       Parr

model:                   4842

annotation:           Dokumente engl.

New Resilient Graphite Gaskets

All Parr HP/HT Reactors are equipped with flat, Grafoil gaskets held in confined gasket grooves with minimum exposure to the reactants. These gaskets are made of a flexible form of graphite which will withstand high temperatures up to the limits prescribed for these vessels, and they will not flow under high temperatures and pressures. They offer excellent resistance to a broad range of corro­sive environments, including oxidiz­ing atmospheres, and under most operating conditions they are reusa­ble. Replacements are relatively inex­pensive and easily installed.

For users who prefer metal gaskets, Parr HP/HT Reactors can be fur­nished with a metal head gasket in a self-sealing, diamond design. These gaskets are usually made of stainless steel, but they can also be made of other alloys. Metal gaskets must be used with great care to protect the faces of the metal-to-metal seal, but with proper maintenance and care, satisfactory high pressure seals can be developed and maintained. An indi­vidual gasket can usually be reused 20 to 30 times before it becomes deformed to the point where it is no longer usable.

Optional Cylinder Openings

All of the floor stand reactors in this HP/HT Series are designed so that either one or two additional connec­tions can be made into the bomb through the top flange on the side of the cylinder without mterfering with the Split ring closure. High pressure tubing is then used for connections to the control panel. It also is possible to offer an opening in the bottom of the vessel for a bottom drain, provided that a suitable valve can be obtained that will be compatible with the reac­tants and the temperatures and pres­sures to which it will be exposed. These optional connections, if required, must be described fully when ordering.

High Torque Magnetie Drives

Sealed magnetic drives in these new reactors ensure positive, leck-prool stirring without the problems whiel. can arise with gland-type seals at higt temperatures and pressures. ThE high coupling torque provided by these heavy duty drives will handlc most stirring loads. If necessary, e double reduction drive System can bE added for use with extremely viscou„ mixtures. Water cooling sleeves arE provided to protect the componenü from high operating temperatures.

Positive Agitation

There are two, six-blade, downward thrust impellers on the stirrer shaft in these reactors, both adjustable on the shaft. In their usual positions the bot­tom impeller serves to keep particles in suspension while the upper impeller is set at the base of the gas-liquid vor­tex to entrain gases into the liquid phase. A guide bearing attached to the thermowell helps to stabilize the shaft.

Controler 4842

Principal Features

- Digital display

- Digital setpoint

- Three term (PID) control

- High temperature cutout

- Microprocessor based system

Enhancement Opitons

- Tachometer Display Module

- Pessure Display Module

- High Temperature Cutoff Module

- RS232C Communications Module

- Solenoid Valve Module

- Ammeter Display Module

- Analog Outputs

The 4842 Controller is a fall feature, microprocessor based, fully digital temperature control system offering adjustable proportional, integral and derivative (PID) action with which the user can tune the controller to a wide range of operating conditions. All con­trol and tuning settings are entered an a front panel keypad while an alpha­numeric vacuum fluorescent display prompts the Operator step-by-step for all setting and tuning operations. Security key Codes prevent unautho­rized changes.

A 25 amp, solid state relay is included to handle the heater load, and variable speed control is provided for the reactor motor. Any three of the listed Enhancement Options can be added to the 4842 Controller.

Protection against runaway temper­atures is provided by a setable high temperature limit, the same as de­scribed for the 4841 Controller. There is also an Output socket for an aux­iliary cooling system. An optional dedicated communications board can be added to the 4842 Controller to allow all actions to be reported via any RS232C, RS422 or 20mA current loop. Battery backup is provided for the controller memory.

Specifications

Input thermocouple                      Type J

Operating range                           0° to 600° C

Readout resolution                       1°C

Setpoint resolution                       1°C

System accuracy                         +/-2°C

control action                               Three term PID control plus limit control

Operating voltages                       115 v and 230 v.a.c.

Maximum switching load             15 amp

Cabinet dimensions Overall        103/4" wide x 10" high x 12" deep