Thermal Equipment Corporation (TEC) was incorporated in 1970 as an outgrowth of Fuel Engineering Corporation (FECO), the world's pioneer Autoclave System manufacturer that began manufacturing Aerospace Autoclaves back in the 1950s. FECO and TEC have developed Autoclave System innovations over the last 50 years that have helped define the Composites industry. Many of TEC's managers, engineers and technicians have been with the company upwards of 20 years, and we are continuing the legacy with new interns in every department.
TEC Autoclave Systems are known for their robustness, quality and reliability that perform well in heavy production environments over long periods of time. Our unparalleled level of experience, quality workmanship and concern for system performance have made TEC the recognized leader in the Aerospace Autoclave industry. This high level of performance is due to the experience and over-engineering of key components such as the closure design, hinge design, door bolt, encapsulated fan motors, heating and cooling coils, our methods of internal sheet metal installation, and other engineering and manufacturing processes that have been pioneered by FECO and TEC over the last 50 years.
In working with Customers to overcome system design constraints, TEC has developed many design concepts that have since become industry standards. There are other manufactures who offer economy type Autoclave Systems, but none can match the quality and experience offered by TEC.
The following is a partial list of Autoclave characteristics that were either originally
pioneered by FECO and TEC, or significantly improved to redefine the application, based
on our many years of experience in the industry.
- Encapsulated Autoclave Fan Motors
TEC was one of the first manufactures to use a fan motor that is internal to the pressure envelope of the Autoclave vessel. The original implementation was to install the motor physically inside the Autoclave with access via a blind flange on the back of the Autoclave. While this worked reasonably well, maintenance proved to be difficult. The innovation by TEC was to use an external motor housing that was at the same pressure as the Autoclave, which provided significantly easier access to the fan motor while reducing the temperature it was subjected to. - Replaceable Sleeved Motor Housing Cooling Coils
Due to the ASME requirements for pressure vessels, any repairs or alterations of the main Autoclave vessel, once it has received ASME certification, require re-inspection and the filing of an ASME “R1” repair report. This process causes delays and additional cost. TEC’s innovative solution was to install sleeves in the motor housing head, which moves the welding of the motor housing cooling coil away from the main pressure vessel, and provides easier replacement of the coil without requiring any ASME paper work or inspections. - Autoclave Door Bolt Safety Locks
Although required by ASME code, the design of the Door Bolt devices varies greatly between Autoclave manufacturers. TEC has developed a very robust design that not only satisfies the basic ASME requirements, but also adds an additional margin of safety. In addition to this superior design, TEC incorporates not one, but two electrical interlock switches on all large Autoclave Door systems. And TEC’s interlock air cylinder uses a custom low pressure spring to insure the cylinder engages at the lowest pressure possible, while still providing reliable operation. - Alarm Wiring and PLC Logic
TEC pioneered a “proof of signal” on all critical alarms. We must have a positive signal to indicate that the condition is okay, which proves the alarm wiring and switches are functioning correctly. A loss of signal will then indicate an alarm condition. - Cooling Coils
TEC has developed a special design for all cooling coil tube sheets to allow for expansion and contraction during heating and cooling. TEC cooling coils also have a slight slope to insure self-draining to prevent corrosion in the coils. - Electrical Pass-Throughs
All TEC electrical and signal pass-throughs have been custom designed to allow flexibility in the Autoclave System design. - Sheet Metal Installation
TEC uses a proprietary method of installing all Autoclave vessel internal sheet metal to insure long term reliability and to reduce buckling due to thermal expansion. The pegs and bands are designed to reduce heat conductivity to the pressure vessel shell by using a smaller 1 1/2 inch band with pegs welded to the shell. High operating temperature TEC Autoclaves also have a notch cut in the shell side to further reduce conductivity and have special heavy duty foil to reduce heat convection through the insulation layers. TEC also uses special insulation techniques to insure staggered seams. - Door Flange Cooling
TEC pioneered the use of flange seal cooling on both the door and shell flanges to reduce temperature, insuring reliable operation of the closure after sustained high temperature operation. The feature is implemented in all TEC Autoclaves designed for operation at 650F or higher. The cooling circuit goes through the vessel shell and is routed close to the parting line. The cooling tubes are held in place by square bars with the cavity filled with heat conductive putty prior to installing the cover plates. - Part Thermocouple Jack Panel Boxes
TEC determined that air penetration along the vessel shell was causing accuracy errors with the thermocouple jack panels. This airflow was exiting at the pass-through assembly, which cooled the back of the jack panels. The jack panels must be within 100° F front to back to provide accurate readings, so to resolve this issue, TEC installs the jack panels in a sheet metal box which keeps the temperature at the back nearly the same as the front. - Autoclave Interior Lighting
TEC pioneered the first interior lights that provided reliable operation. Testing and research determined that a pressurized halogen bulb would be required to survive the harsh conditions of a pressurized Autoclave. TEC then designed a suitable housing using high temperature sockets and wiring. - Site Glasses with Camera Systems
TEC pioneered the use of video cameras and recording systems to document the internal events during an Autoclave cure cycle. We use a quartz lens assembly suitable for the pressure of the Autoclave and provide a water cooled flange to reduce the lens and shell temperatures. The camera housing is designed to provide easy access to the camera while providing explosion protection in the event of a lens failure. - Ultra High Temperature (1,500° F)
TEC has developed several specific enhancements used for ultra high temperature applications, including a nitrogen purge for the motor housing. This insures a constant airflow from the motor housing to the internal Autoclave work space to reduce fan motor temperatures.
We also developed a special cocoon style insulation technique that maintains a slight clearance between the insulation and the vessel shell, which utilizes a nitrogen purge at several locations on the shell. The helps reduce external vessel shell temperatures and the amount of insulation required. - Rear Head Assemblies
TEC pioneered the use of seal welding on all Autoclave rear head sheet metal. As this is the high pressure zone for the fan system, we determined that the air loss through the seams on this sheet metal was detrimental to the system efficiency. This unwanted airflow also contributed to the problems seen with the inaccuracy of part thermocouples. - “Autoclave Computer Control System” (ACCS) Software
TEC was the first Autoclave System manufacturer to offer complete computer control utilizing part feedback. Our ACCS software was completely designed and written by an in-house software team based on the input from customers.
ACCS is a complete control and data acquisition system for the processing of composite materials in Autoclaves, Ovens and Presses. The system may be installed on existing or new process equipment, and features include part data logging, and control by rate, threshold pressure, tool, and serial number. Complete interactive operator display with graphics and prompting is included, and report generation is available in Summary, Graphical, and Detailed formats. Also included are a Customer computer interface cure cycle storage library and cycle data archiving on a CD drive, tape or the customer’s network.
TEC was the first to use custom Autoclave specific software modified for use on a standard personal computer. ACCS is designed to control the surroundings that influence the part in the Autoclave, and was designed to run on a Windows operating system with an off the shelf Pentium type computer. - Vacuum Valve Assemblies
TEC developed the first self contained resin trap with internal filtration. These are intended mainly to act as a separator to collect resins, alcohol and water. Their efficiency can be increased by using a chilled water system. - Vacuum Manifold Valves
TEC pioneered the first self contained vacuum valve assembly to allow the use of partial or full vacuum to a bagged part. The valves could be readily cleaned and rebuilt from the front of the control panel without the need to be removed. These valves have since been replaced with more sophisticated vacuum systems. - Shuttle Valve Assemblies
TEC was the first Autoclave System manufacturer to design custom shuttle valves that offer automatic calibration. These assemblies were electrically controlled and allowed switching the desired transducer from “Read” to “Calibration” and from “Source” to “Vent”, completely by the computer. - Horizontal Split Autoclave
As part of TEC’s continued efforts to support Customers with specific application equipment, we designed and fabricated the world’s only horizontally split Autoclave System, fitted with a heated platen in the lower section. - Custom Electronics
TEC was at the leading edge of Autoclave automation and designed and engineered many of the specific electronics required for our state of the art control systems. These items were custom fabricated to TEC’s specifications and included part vacuum transducers, Autoclave pressure transducers, signal splitters and zero-span networks. TEC also designed and fabricated the world’s first IEEE-488 transfer box. No other Autoclave manufacturer could provide this type of transfer box which was critical to our ACCS redundant computer systems. The transfer box was used to transfer the communications of two computers to various devices, including printers and relay boards. And TEC was the first to incorporate computer controlled vacuum valve assemblies by modifying relay boards to meet our needs.