Friday, June 9, 2017

Hotfoil-EHS Attending the 2017 Global Petroleum Show in Calgary

Hotfoil-EHS is pleased to announce our products will be on display at the Global Petroleum Show on June 13 through 15, 2017 at the Stampede Park in Calgary, Canada.

Hofoil-EHS will in exhibiting as a guest of Stein Industries in London, Ontario. Stein will be exhibiting its high quality, custom designed, affordable induction heaters built to withstand harsh environments with wide applications.

This is a great opportunity to see major welding equipment vendors and new technologies being introduced. If you plan on being at the Global Petroleum Show, please stop by the Stein Industries at booth 4404.

The Global Petroleum Show provides direct access to the entire supply chain, innovative technologies, products & services and a massive number of educational seminars within the energy sector. Global Petroleum Show is an industry leading event, where more than 50,000 energy professionals from more than 90 countries converge for three days to strengthen business relationships, network, and do business with more than 1,000 exhibitors. During this pivotal, evolutionary period for the oil & gas sector, it’s never been more vital to re-connect with your global industry. From upstream to downstream, GPS provides a forum where business gets done.

Wednesday, May 31, 2017

Resistor Controlled Welding Machines

resistor controlled welding machines
Resistor controlled welding machines by AFTEK.
Resistor control has been used in multi-operating welding systems in shipyards and heavy construction for decades. In the heyday of nuclear power plant construction in the USA, nearly all were built using multiple-operator systems. From the thirties until about 1990, nearly all multiple-operator systems were the designed similarly. They used a large bulk power supply with “grids” connected by cables to form a system of distributed power. This system minimized the use of high voltage primary power, distributing 75-80 volts of secondary voltage instead.

As these systems grew in popularity, the concept of “packs” became popular. These packs provided 2, 4, 8, and 16 arcs in a steel rack, and all being connected to a separate power supply. A now defunct company named Big Four developed the concept of connecting multiple-operator systems in a loop arrangement, which resulted in greatly improved voltage stability. In 1990, this loop concept was further refined into integrated, modular welding packages. These newly designed systems provided an internal power supply sufficiently sized to provide power to all the arcs without any interference.

Loop systems are still being used today. They are viewed as a very economical welding alternative. For example, for a loop that needs twenty MIG arcs, it is possible to use (4) 500-amp power supplies connected to a single 500 MCM cable which circles the work space. Twenty control modules can be connected wherever needed on the closed loop of cable. A huge cost savings is realized in having to establish just four (4) primary connections instead of twenty (20).

Most conventional arc weld­ers use a transformer-like device called a reactor to control the "heat" of the welding arc. If you examine the Voltage/Amperage (V/A) curve for a con­ventional constant current (or constant voltage) welding power supply, you’ll see spikes. This is inherent in the design of conventional arc weld­ers. The V/A curve of a resistor controlled arc welder, on the other hand, is a straight line.

Resistor controlled arc systems provide more consistency of power - if you shorten the arc, thus lowering the arc voltage, the current will increase, and maintain virtually the same power (heat). If you lengthen the arc, you raise the voltage, but the power remains virtually constant. Why is this important? In any welding process, increasing the amperage increases penetration and increasing the voltage widens and flattens the head (and reduces penetration). With a resistor controlled arc, if you are welding along the seam and it closes, shortening the arc length will increase penetration. If the weld opens, lengthening the arc will lessen the penetration and widen the weld. This provides excellent control right in the electrode holder.

AFTek, a US manufacturer located in Chattanooga, TN and division of Hotfoil-EHS, is the sole remaining manufacturer of resistor controlled welding machines in the USA. Their resistance welders are an acknowledgement of the superior design Big Four developed years ago, while improving performance with edge-wound coils for better heat dissipation (thus better current control) and rotary switches for current selection, even under load.

Wednesday, May 10, 2017

New Product: The ISG Wireless Heat Treatment Controller

ISG heat treat controller
The ISG heat treat controller.
The ISG heat treatment controller is a panel-mounted controller which can easily be connected to thyristor, electrical contactor, or induction/inverter driven power sources. The controller has 2 analog outputs, 5 digital outputs, 2 analog inputs and 2 digital inputs.

The ISG is capable of controlling two measurement points and monitoring two measurement points. If more measuring points are required, up to 14 controllers can be daisy-chained to the same heating process via cables or wireless, while all being managed from a single computer. The ISG communicates with PC's via Zigbee radio or with an RS485 Serial port.

All routines or process plans are created with ISPort software. After the process is started, the routine and the process data is saved to the PC, and also to the controller's memory. This enables the controller to work independently should the connection between ISG and computer be lost. The ISG includes a convenient LED process display and additional process status and alarm LED's.

For more information on the ISG heat treatment controller, visit http://www.hotfoilehs.com or call 609.588.0900.

Wednesday, May 3, 2017

Custom Built Heat Treat Furnaces

Custom Built Heat Treat Furnaces
 15'x15'x60' Custom Furnaces
Hotfoil-EHS has extensive heat treating furnace design and fabrication experience. From small, low-throughput furnaces, to much larger high yield furnaces, to rail-driven furnaces, Hotfoil-EHS Design Engineers and Fabrication Shop have done it all.


 Heat Treat Furnace
Capable of handling 45,000 lbs.
Recently Hotfoil-EHS provided a customer with a heat treat furnace that is 15'x15'x60' that accommodates up to 45,000 pounds of material. Two, 5 million BTU burners heat the furnace to 1650 deg. F. The furnace travels on a track, back and forth, to accommodate two beds for greater production.

 Heat Treat Furnace
Rail system with (2) beds


For more information, visit http://www.hotfoilehs.com or call 609.588.0900.




Sunday, April 16, 2017

A Better Choice in Heat Treatment Control Systems

ICE Star Heat Treatment Controllers
Ice Star, a Finnish company, engineers and manufactures heat treatment controllers for electric and gas furnaces, as well as for induction and resistive heating consoles. The company manufactures the most advanced metal heat treatment control system available today. Since 1984, they have been laser-focused on the development and advancement of industrial heat treatment controllers and software.

ICE Star Model ISG Heat Treatment Controllers
ICE Star
Model ISG
Heat Treatment Controller
Ice Star’s founder, Esa Santala, has decades of knowledge and experience in the heat treatment industry. He developed one of the first processor controlled multi-channel controllers and has since been building even more innovative products.

Ice Star controllers do not require a separate recorder. Ice Star controllers monitor all critical heat treatment variables - temperature, time, soak, upsets, diagrams, events, alarms etc. - and then provide extremely detailed records for each. Additionally, with ISPort software, you can monitor and control the heating processes directly from remote process displays and computers.

For more information about Ice Star in North America, visit Hotfoil-EHS or call 609.588.0900.

Sunday, April 9, 2017

Hazardous Area Heater Control Systems for Coal Hoppers and Conveyors

Explosion proof control system
Explosion proof control system.
A major hazard in coal burning utilities is the transfer and storage of coal due to the presence of highly combustible coal dust. Mitigating the risks of combustible dusts eliminate the potential for dust explosions. It is critically important that any coal handling or coal storage facility have access to experienced application engineers who understand the specific requirements when handling coal and managing coal dust.

Electric heat is very often used to prevent coal freeze-ups in hoppers and conveyors. The most common electric heaters used are are exterior mounted panel heaters with carefully calculated watt densities to keep sheath temperatures low. A less preferred solution is the use of tubular heating elements that may have higher sheath temperatures. Tubular heaters are usually clamped or stud-welded to the exterior of the coal hopper or conveyor chute.  In either case, a control system must be employed to maintain operating temperatures and to safely limit temperatures below dust ignition temperatures.  Since the presence of coal dust in the atmosphere is considered normal, the use of explosion proof housings, conduit, and wiring practices is required for these control systems.

Explosion proof control system
Internal view.
Hotfoil, a New Jersey manufacturer of electric hopper and coal handling heating systems,  designs, engineers, and fabricates custom control systems specifically for these applications. 

With decades of experience in hopper, conveyor, and tank heating systems they provide their customers with a single-source, turn-key, electrical heating and control system solutions provider. All products are 100% quality tested prior to leaving the facility, and an added plus is that they provide on-site start-up assistance.

Thursday, March 30, 2017

Electric Heating and Control Solutions for Power Generation

Hotfoil-EHS specializes in electric surface heating systems in power plants for fly ash hoppers on electrostatic precipitators or baghouses, coal and material handling systems, tanks, and pipes.

For more information, visit http://www.hotfoilehs.com.

Tuesday, March 28, 2017

Weld Heat Treatment is Critical to Structure Integrity

Welding pre-heat
Welding pre-heat is critical to the quality of the weld and
and the integrity of the structure.
In any large scale welding operation (such as pipeline welding, shipbuilding, boiler fabrication) heat treatment is critical to the quality of a weld, and therefore critical to the performance of a structure, and never should not be taken lightly.

When in doubt, review of industry code or a consultation with a welding expert is imperative. Welding code is the first determinant to whether pre-heating is needed. Welding code carefully specifies the minimum preheat temperature, the soak time, and the welding process. Many criteria are considered by welding codes, all gathered from years of rigorously tested data. This data is accumulated from many sources, including metallurgical science, chemical properties of materials, and radiographic analysis.

In its simplest form, weld heat treatment is the process of heating the base metal (parts to be welded) to a desired temperature prior to welding, and then allowing it to cool at a given rate under controlled conditions. The specific temperature to which the part needs to be heated (before welding) is referred to as the “preheat temperature”.

There are several key reasons why it's important to preheat before welding. 
  • A preheated part cools more slowly, which slows the overall cooling rate of the welded part. This improves the metallurgical (crystalline) structure and makes it less prone to cracking. 
  • Hydrogen that may be present immediately after a weld is also released more efficiently, which further reduces the possibility cracking. Preheating also mitigates stress from the shrinkage at the weld joint and nearby metal. 
  • Pre-heating reduces the possibility of fracture during fabrication due to brittleness.
Electric welding preheaters, known as "ceramic mat heaters", are rugged and flexible heating elements designed so that they conform uniformly around the weld and surrounding area.  Ceramic mat heaters are normally controlled by a power console that uses thermocouples and electronic controllers to regulate, monitor, and many times record, the preheat temperature profile.

Another less preferred method to heat the target piece is with a torch, or open flame, but this method carries safety concerns as well as controllability issues. Furnaces are also used, but these typically require the transport of the target piece off-site.

Induction heaters offer an attractive alternative for safety, portability and controllability. Induction heating is unique because it uses molecular excitation as its source of heat, as opposed to open flames or external electric elements. Induction heating works very quickly, and since there is no contact with the target piece, there are far less concerns about part contamination.  Many industrial processes use induction heating when very high temperatures and uniform control is desired.

Each welding application has it's own unique set of circumstances which dictate the optimal heat treating method.  It is always best to contact an expert and solicit their opinion on your best available option.

Friday, March 17, 2017

Welding Heat Treatment Power Consoles

Welding Heat Treatment Power Consoles
Welding Heat Treatment Power Consoles by Hotfoil-EHS
When it comes to Hotfoil-EHS power consoles, there's no cutting corners. By using thicker gauge sheet metal and tubing, top quality electrical components, and quality craftsmanship, Hotfoil-EHS power consoles provide years of reliable and trouble-free service.

Power consoles are standardly offered in 6, 9, 12, 18, and 24 zone configurations with a variety of control and recording systems. All Hotfoil-EHS power consoles are available in Stainless Steel and can be customize to your requirements.

Have a special requirement? Just ask. Need a special color, coating or controls? Hotfoil-EHS is eager to provide a custom power console to meet your exact needs.

Temperature recorders are available for applications requiring documentation and certification. Fully automatic controllers are provided when specific heat-up and cool-down profiles are needed.

EHS manufactures and sells accessories including:
  • ceramic heaters, 
  • thermocouple attachment units (TAU) 
  • pin welders 
  • hardness testers 
  • thermocouple wire 
  • insulation

Monday, February 27, 2017

Eliminate Costly Hopper Pluggage with Electric Hopper Heaters

hopper heaters
Modular, metal-clad hopper heaters
installed on large hopper.
Fly ash is a by-product of coal fired and waste-to-energy fired electrical generating facilities. Fly ash is a combination of dust and fine particles produced during combustion. Environmental laws require fly ash to be collected and not released in to the atmosphere. Large collectors called electrostatic precipitators combined with a system of filters extract fly ash from the flue gas and dispense the fly ash in large steel hoppers prior to being dumped in to containers and transported.

Due to the temperature differential between the hot internal temperature of the hopper and the cooler exterior, condensation forms on the internal wall surfaces, The condensation, combined with the fly ash, creates a concrete-like material that bonds to the hopper walls. The accumulation of this material eventually clogs the hopper to the extent it cannot be emptied. At this point, the only way to free the clogged material is with sledge hammers and pneumatic tools and long periods of downtime and the related expense.

To prevent the fly ash and condensate mixture from forming,
electric heaters are bonded or clamped to the exterior walls and throat of the hopper. Because the environment is normally very dirty with high vibration, “hopper heaters” are designed to withstand to meet these mechanical and environmental stresses.


Hopper heaters come in a variety of physical sizes, voltages, and wattages. Most often, hopper heaters come in pre-engineered sets that have been specified and configured by an applications engineer.

For more information on any hopper heating application, contact Hotfoil-EHS for a free consultation. Visit http://www.hotfoilehs.com or call 609.588.0900.

The Hotfoil-EHS Fusion 45 Induction Heating Console

Induction heating can improve your bottom line by decreasing weld failures, and decreasing setup and tear down times. The technology allows for accurate temp control, without heavy electrical service or complicated controls. The portability and ease of use will allow you to heat more welds faster.

For more information call Hotfoil-EHS at 609.588.0900 or visit http://www.hotfoilehs.com.

Sunday, February 26, 2017

Induction Heating Provides Welders Uniformity and Shortens Welding Time

Welder’s must pay strict attention when it comes to preheating, interpass temperature control and stress relieving. Torches takes too long and make it difficult to maintain heating uniformity. Plus there’s the issue with open flames and the expense of fuel.

Ovens are great for uniformity and control, but require transport and time. They're certainly not convenient.

A great alternative, one that provides excellent uniformity, control, and convenience, is induction heating.

Induction heating is unique because it uses molecular excitation as its source of heat, as opposed to open flames or external electric elements.

Induction heating works very quickly, and since there is no contact with the target piece, there are far less concerns about part contamination.  Many industrial processes use induction heating when very high temperatures and uniform control is desired.

Its important to note that the heat is created from inside the object itself, with no open flame or external electric heat source.

Induction heating is used to heat conductive materials. Developed in the early 20th century, it quickly became a popular choice for hardening military equipment parts during wartime. Because of induction heating’s controllability, speed and consistent output, its popularity continued to grow as new manufacturing and production methodologies were developed. Today, induction heating has become a popular technology for the welding industry to provide pre and post-weld stress relief.

Induction heaters provide temperatures and cycle times hard to achieve otherwise. By virtue of their high temperature capabilities, very fast heat up times, precise application of heat, excellent controllability, and ease of setup / breakdown, the use of induction heating has been know to cut 30% to 50% of total weld cycle time in real-life welding applications.

Induction heaters consist of a few primary components: An electromagnet and an electronic oscillator that passes a high-frequency alternating current (AC) through the electromagnet. RF (radio frequency) energy is transferred into the workpiece via electromagnetic waves. These alternating magnetic waves penetrate the object, creating electric eddy currents. These eddy currents (Foucault currents) flow through the target piece and produce heat.

Pre and post-weld heat treating (stress relieving) is a growing market for induction heating systems because it offers significant benefits such as excellent heat placement and distribution, lower cycle times, safety, ease of use, and efficiency.

For more information about induction heaters for pre and post-weld heat treating visit HotfoilEHS at http://www.hotfoilehs.com or call 609.588.0900.

Tuesday, January 31, 2017

Don't Let Frozen Aggregate Clog Your Process Equipment

FRP hopper heaters
FRP hopper heaters
FRP chute heater
FRP chute heater
Processing lines in coal mines, quarries, cement plants, mining facilities, and power plants have a special problem in very cold weather. The coal, sand, cement, ores, or other mined products they handle can freeze and cause equipment outages. The combination of trace moisture mixed with aggregate material, plus freezing temperatures, combine for major problems with conveyors, hoppers and chutes. When the aggregate hits the cold steel surface, it instantly freezes (flash freezing). The bond between the frozen aggregate and the steel wall is virtually unbreakable, and can cause long down-times with the equipment. Maintenance people have their own, time-tested curative solutions - torches and hammers - but installing preventative measures is clearly preferable.

FRP trough heater
FRP trough heater
The FRP heating panel, a waterproof, dust tight, and vibration resistant heater is an excellent preventative solution. FRP heaters are designed to be used in the high vibration, corrosive and dirty areas where they are installed. Available with FM approval for use in hazardous areas, they provide an easily customized panel that conforms to the shape and size needed to fit any chute or hopper. Additionally, they are lightweight, can be applied to flat or curved surfaces, and are very easy to install and maintain.

FRP trough heater
FRP trough heater
For more information on chute, conveyor, hopper or pipe heating, contact the experts at Hotfoil-EHS by visiting www.hotfoilehs.com or calling 609-588-0900.

Saturday, January 28, 2017

Custom Control Panel Fabrication: Start to Finish

Hotfoil-EHS provides custom control panels for a variety of applications. Know for their quality, service, and availability, Hotfoil's experience in designing systems is broad.

Hotfoil-EHS has traditionally focussed on electric heating systems including heating tanks and vessels as well as electric heat tracing, but more recently has developed an expertise in combustion heating system controls. For more information visit http://www.hotfoilehs.com or call 609-588-0900.

Below is a time lapse video of a custom design control panel being fabricated from start to finish.

Sunday, January 22, 2017

Applying Ceramic Mat Heaters for Pre and Post Weld Heat Treatment

Designed for pre and post weld heat treating, ceramic mat heaters function efficiently for both curved and flat applications. The flexibility of these heaters provides a convenient means to heat treat large metal surfaces in the field.

The application of ceramic mat heaters is straightforward - the heater is placed directly on the part to be welded, insulation is normally laid over the heater, and voltage is applied. A thermocouple is tack-welded near to monitor the part. The part is brought up to temperature and then the welding is done. After the weld, the part is cooled at a controlled rate.

Ceramic Mat Heaters
Welding a large pipe with localized heating using
ceramic mat heaters.
Pipe prep before welidng
Preparing the pipe for the weld and allowing
the heaters to raise the temperature of the pipe.

ceramic heaters before weld
Wrapping ceramic mat heaters around
spool piece.
Close-up of ceramic mat heaters around
spool piece.

Wednesday, January 11, 2017

Ceramic Pad/Mat Heaters: The Tried and True Way to Heat Treat

Ceramic mat heater
Ceramic mat heater: Proven performance over time.
Heat treating large metal surfaces in the field before and after welding is usually a challenge. Over the years, products have been developed that perform well and withstood the test of time. One of these products is the ceramic pad heater.

Ceramic pad heaters (also known as mat heaters) are constructed of interlocking sintered alumina ceramic beads (usually pink or white in color) which insulate an 80/20 Nickel/Chrome multi-strand wire (the resistance element).

Ceramic pad heaters are designed for most pre-heat and post-heat treatment requirements on weld joined materials (stress relieving). Available in numerous sizes, shapes, configurations, voltages and wattages, they can be used up to 2150°F in various weld heat treating applications.

Ceramic mat heater
Various shapes and sizes.
They are designed for re-use in a wide variety of heating applications. Their flexible design allows for conformance and good heat transfer to the target part. Their rugged design is well suited for most industrial environments where shock and vibration is a reality. Ceramic pad heaters can be used with or without the application of insulation. The use of insulation will greatly speed up the heating
process as well as more efficiently retain the heat for soaking.

For more information on the use and installation of ceramic pad (mat) heaters, visit Hotfoil-EHS at www.hotfoilehs.com or call 609.588.0900.