Steam heating Systems

The chamber and doors can be heated via a hydronic heating system specifically designed for free circulation of water throughout the chamber's jacket and doors. The heating system is capable of providing an empty chamber temperature uniformity up to +/- 0.5 °C at a set point temperature of 50 °C (122 °F)

The heating system consists of a stainless steel shell and tube heat exchanger, pump assembly, PLC control and instrumentation.

The temperature of the water can be controlled by a PID function provided within the PLC software. This PID function is essential to reach the selected set point rapidly, and also to maintain the water temperature within a maximum deviation of +/- 0.5°C. In order to avoid an over-temperature condition, the heating program includes an alarm that would shut the heating power.

Another redundant safety system consists of a hard-wired electrical circuit (independent of the control system) that disconnects the electrical power to the heating system, if the temperature exceeds determined set point.

Stainless steel sensors with thermowell are used to sense the temperature at the heat exchanger and pump.

Vacuum Systems

Typical pressure vessels applications include product preconditioning, air removal, or degassing phases, Quetzal can offer a broad line of closed loop vacuum systems for each of these applications. The systems are usually comprised of a mechanically sealed water ring vacuum pump, water storage tank and a heat exchanger for cooling the seal medium. The components are mounted on a vibration-free base that prevents low frequency vibrations to be transmitted to the pump mounting area.

The system is connected to the chamber via AISI 304 stainless steel piping and a pneumatic valve.

The water storage and EtO separation tank is designed to efficiently separate the gas from the seal medium. In addition, the volume of the tank is sized to reduce the cooling water flow rate requirements. The tank is of welded construction and is fabricated from AISI 304L stainless steel or 316L according to customer applications.

Systems can be designed to evacuate a chamber to 28"Hg. in less than 10 minutes. Optional mechanical dry booster pumps can be installed to increase the performance of the vacuum system. The booster pumps are designed to exhaust large volumes of air and condensable gases up to an effective pressure of 1 torr. or less.
For hazardous locfations, motors on the system can be selected in accordance with National Electrical Code (NEC-USA), Explosion Proof Class 1, Division 1.

Safety Systems

In order to protect the operator and the equipment, the following safety devices can be added to the vessel.

• Safety valves and rupture disk in series for chamber overpressure.
• Safety valve for jacket hydraulic expansion.
• Hydraulic pressure release device for the jacket.
• The Flexidoor system for chamber overpressure.
• A temperature wall sensor attached to chamber and jacket
• Door does stop its sliding movement if any object interferes with its stroke.
• Chamber vent with valve for chamber ventilation.
• CFI. (Control Facilities Interlocks)
1.Fire alarm system
2.Ventilation system
3.Gas emissions control or scrubbers
4.Ambient monitoring systems
5.Utilities; Air compressed, Steam, Chillers, N2 source, Electricity,
SCADA, etc.

In order to protect the equipment a rupture disc can be installed in the upper part of the chamber, following the recommendations of the ASME Code, Section VIII, Division 1 Chapter UG-125 / UG-134 / UG-127.

All door interlocks (switches, sensors, etc.) are provided with independent redundant backup.

Specifications:

All panels are submitted to stringent inspections under QA updated procedures before they are released to the customer field.

In addition, each panel receives complete point-to-point testing to comply with the design and the specification.

Factory acceptance testing includes; Verification, checking and visual control of all the electrical, electronic, pneumatic and/or any other element installed in the cabinet/s, proper adjustment of terminals and/or hoses, continuity test, insulation resistance, checking the inputs and outputs of the PLC, intrinsically safe components and wiring compliances and full functional testing connected to our CPSU.

Panels can be certified and labeled in accordance with UL508 - Underwriter's Laboratories American Standard for Industrial Control Panels.

Control Systems and supervisory stations

Hardware
Industrial pressure vessels normally are subject to complex process with special requirements. When designing such systems, one must consider all of the requirements including product safety, personnel safety, equipment safety, process validation and quality monitoring of the product.

The following criteria is incorporated in the design of Quetzal's exclusive software:

• Safe working conditions
• Safe doors operations
• Vessel components protection
• Process protected against unexpected conditions ("what ifs")
• Product validation conditions to meet specific regulations or cGMP.
• Economy of time and resources
• Records of process batches

To satisfy these requirements, Quetzal pressure vessels can be fitted with a microprocessor control system as standard equipment.

The PLC shall execute a software program designed by Quetzal's Engineering and Control Department, which determines the state of the process and makes the appropriate decisions based upon such state. It is capable to react properly under all possible "what if" conditions. Both the routine performance and any deviations are extensively tested during the design stage.

One of the main features of the PLC and software is to eliminate operator, product and system risks. The operation of the door is continuously analyzed by means of signals produced by opening, closing, locking and retracting feed back sensors.

Quetzal is experienced in validation requirements imposed by the United Stated FDA (Food and Drug Administration), that requires documentation proving that the control system will meet design specifications under normal or abnormal conditions.

Control Station
Quetzal can design the control system as a Distributed Control System (DCS). As a DCS, the modular PLC does not concentrate responsibilities in a single device. The unit is specially designed for industrial environmental supporting the hardest values of temperature and humidity.
The control system configuration consists of a controller connected to the supervisory station. The controller communicates with the field through one or more input/output sub-systems, which are located in the controller cabinet itself. The size of the PLC can be designed in conjunction with the customer engineer staff by studying both the processes needs and the interlocks requirements.

Supervisory Workstation
Quetzal's supervising systems allow for thorough monitoring of all stages of the a process process. The workstation displays the values of process variables or the graphics corresponding to such variables as a function of time.

The Supervisory Workstation is the interface between the operator and the process. The control software displays supervisory information and allows many tasks to run concurrently. The control software is Quetzal's Supervisory Software.

This software can be installed in the Supervisory Workstation. The workstation consists of an IBM PC compatible computer such as Hewlett Packard (HP) with the latest Pentium processor equipped with a serial port, a parallel port, 4.0 GB Hard Drive, 32 MB Ram, 3.5" Floppy drive, 20" SVGA Monitor, Keyboard and mouse. This supervisory system runs on a Windows environment.

High-resolution color graphics displays change dynamically to highlight process or alarm status changes. Guide messages prompt the operator to answer when alternative options can be taken. Supervising systems digitalize all the parameters and store them in digital form in the computer hard disk, for statistical analysis and validation purposes.

A printer connected to the workstation provides a printout of all events and status of alarms produced at intervals of 2 minutes and at the end of cycle (The software will write to the hard disk every 30 seconds). The system includes an audible alarm to draw the operator's attention when an abnormal condition occurs.
At the end of cycle, the control system shall record a complete cycle summary in an un-recordable format (example: CD-ROM).