Tag Archives: burn protection

High Temperature Strip Curtains

Continuous conveyor ovens are widely used in a variety of industrial processes including composite curing and heat treating.  The entrance and exit points of these ovens represent significant areas for potential heat loss and energy inefficiencies.  Without a proper heat barrier system these openings can be the culprit for thousands of dollars in wasted energy cost.  In addition, regulating and controlling critical process temperatures can become a daunting task with inadequate heat containment.

Utilizing Worbo’s unique high temperature strip curtain system, energy costs may be significantly reduced and process temperatures may be accurately controlled.   These strip curtains serve as an effective thermal barrier while allowing for the passage of parts through the oven chamber.   Unlike traditional PVC strips that will break down at moderate temperatures the Worbo solution can withstand excessive temperatures and will continue to function effectively up to 1000oF.

Worbo strip curtain
Worbo strip curtain

A typical example of a proven and extremely effective Worbo strip curtain design consists of a double layer heat barrier system.  In this system the inside face of each strip if fabricated from Worbo’s exceptional Eko-ThermTM heat reflective material.  This unique material serves to retain convective heat with in the oven chamber in addition to preventing radiant heat from escaping through the oven door.  The outside face of each strip is fabricated from Worbo’s extreme duty MSA96 (96 oz/yd2) silicone coated fabric offering outstanding durability and abrasion resistance as moving parts are transferred though the oven opening.

 
MSA96 side of strip curtain
Outside face of strip from extreme duty MSA96
 
Eko-Therm side of strip curtain
Inside face of strip from heat reflective Eko-Therm

In addition to generating significant energy cost savings, Worbo’s high temperature strip curtains offer the following key benefits:

  • Reduce the risk of workplace burn hazards near the opening of the oven.
  • Strips are easy to install and individual strips are simple to replace should they become damaged without the need to replace the entire curtain.
  • Excellent abrasion resistance and exhibit outstanding durability as parts move in and out of a conveyor oven.
  • Allows for oven temperatures to be accurately controlled ensuring product consistency and quality is upheld.
  • Manufacturing cycles are increased as the thermal barrier facilitates faster oven pre-heat time. 
  • Strip curtains may be supplied in a variety of widths and lengths to custom fit virtually any oven opening.

Worbo’s heat resistant strip curtains are tailor made for each specific application in consideration of temperature constraints, environmental conditions, cycle frequency, oven geometry, etc.  Contact the design team at Worbo to assist with your continuous conveyor oven application. 

 

Cool-Skin Elbows and Tee’s

In response to a growing demand from our customers, Worbo is excited to announce the release of a new product line of easy to install elbow and tee insulation sleeves for high temperature applications.   Introducing Cool-Skin elbows and tee sleeves by Worbo.

These products offer a fantastic complement to our extremely popular line of Cool-SkinTM sleeves.  They are a perfect solution for insulating hoses and process lines that contain a tight bend radius or for lines that have tee intersections.   Traditionally it has been a challenge for plant engineers and insulation contractors to provide a satisfactory and effective thermal barrier in these areas.  Worbo’s wonderfully simple solution enables our customers to quickly and easily install these removable Cool-SkinTM  insulation components around elbows (from 45’s to 90’s) and at tee junctions.   They offer a very precise fit around a wide variety of diameters to maximize insulation coverage to minimize heat loss and to prevent burn injuries at these tricky locations.

 
Cool-Skin 90 elbow
Cool-Skin 90 elbow
 
Cool-Skin 90 elbow
Cool-Skin 90 elbow
 
Cool-Skin Tee
Cool-Skin Tee
 
Cool-Skin 45 elbow
Cool-Skin 45 elbow

Cool-SkinTM elbows and tees are fabricated from the same tried and tested materials that make up our existing Cool-SkinTM sleeve products.  They are equipped with a durable abrasion resistant jacketing system that encapsulates a clean non-fibrous insulation medium exhibiting an extremely low thermal conductivity to provide a very efficient thermal barrier.  As with many of our Cool-SkinTM products our elbows and tees are supplied with a hook and loop closure for easy installation and removal. 

For applications where radiant heat is a concern our Eko-ThermTM jacketing system may be supplied as an alternative to the standard yellow jacket.  The combination of our shiny aluminized Eko-ThermTM material coupled with our non-fibrous insulation medium offers an effective barrier from conductive heat sources as well as from radiant heat sources.   Up to 90% of radiant heat will be reflected away from the low emissivity and shiny surface of the insulation component.  This doubly effective technology will ensure that the process temperatures can be accurately maintained with a minimal insulation wall thickness.

Eko-Therm elbow
Eko-Therm elbow

This new exciting line of products is yet another example of the how the Worbo research and product development team has demonstrated out of the box thinking to create cost effective and innovative thermal protection solutions.   

 

 

“Safe Touch” Insulation

It is well known that providing insulation for hot process lines and equipment makes good economical sense by reducing operating costs at a time when energy prices are skyrocketing.  A Worbo insulation system could easily pays for itself within a few months of installation.  However, often what motivates our customers to implement an insulation system is not simply economics but rather safety concerns.   In today’s market place an increasing number of responsible industrial companies are committed to ensuring the safety of their valuable human resources. 

Hot process lines and equipment represent a significant safety hazard and when it comes to high-temperature operations “safe touch” conditions are key to establishing a safe work environment. 

ASTM C1055 (Standard Guide for Heated System Surface Conditions that Produce Contact Burn Injuries) has determined that the most probable time for a worker to come into contact with a hot surface in an industrial setting is approximately five seconds.  ASTM C1055 further states that the average person can touch a hot surface of 140oF for up to five seconds without sustaining irreversible damage.  For this reason 140oF is widely recognized to be the “safe touch” condition.  However, often in an environment with high ambient temperatures or where there is an increased risk of employee contact, many plant managers and process engineers prefer to implement a “safe touch” temperature of 120oF to further minimize the risk of injury.

Worbo offers several options and thousands of variations of our high temperature “safe touch” insulation covers for virtually any configuration of equipment.  Often equipped with straps, velcro® or fasteners for ease of installation and supplied in the proper thickness a Worbo insulation cover is a very effective solution for reducing surface temperatures down to ASTM C1055 recommendations and below.

cool-skin safe touch insulation safe touch insulationsafe touch insulation sleeve

Typical Worbo “safe touch” Insulation Covers


Determining the best “safe touch” insulation system

Once a Worbo customer has identified the need for “safe touch” insulation it’s up to the Worbo engineering team to design the best possible system.  Choosing an insulation solution will be established in consideration of the following parameters:

Insulation Material – The effectiveness of an insulation solution is greatly dependent on the type of insulation material.  All materials have temperature limitations and it is important to select a material that is capable of withstanding the environmental exposure temperatures.  In addition it is important to select an insulation material that has a low thermal conductivity to maximize its effectiveness as an insulator.   

Ambient Temperature – This is the temperature of the air in the space surrounding the insulation.  A higher ambient temperature will lead to a higher temperature on the outer surface of the insulation.

Air Flow – In an area where there is significant air flow this will result in a substantial decrease in the surface temperature of the insulation.  Often in the interest of safety the Worbo engineering team will ignore this parameter to ensure that the insulation is effective in providing a “safe touch” conditions in still air environments.

Outer Jacket Material – The outer jacket material of an insulation cover will release absorbed heat through a property called thermal emissivity.  Materials that exhibit high emissivity will release more heat away from its surface than materials with lower emissivity and therefore produce a lower surface temperature.  Materials such as Worbo’s MSA17 have a high emissivity and are a good choice for the outer jacket of an insulation system to produce “safe touch” conditions.

Insulation Thickness – The most significant design parameter in establishing a “safe touch” insulation solution is in most cases is the thickness of the insulation.  Intuitively, it makes sense that the thicker the insulation, the more effective it will be a reducing the surface temperature down to “safe touch” conditions.  However, it is important to note that the relationship between the thickness of the insulation and the surface temperature is not linear.   In other words, doubling the insulation thickness will not double its effectiveness as an insulator. 

Below is a simplified calculation to demonstrate how the thickness of a Worbo “safe touch” insulation system may be determined in consideration of the above noted parameters.  

 Calculating Insulation Thickness

If your employees are exposed to a high temperature hazard and you are not sure what the best option is, call the engineering team at Worbo and they will be happy to help you.  It’s what they do best!