TEMPERED HEAT SHIELD
Glass for Industry
reflective glass for INFRARED RADIATION in industry
The RADIANT Brand Tempered Heat Shield is specifically designed to be placed where high radiant heat conditions exist in industry today.
This special glass will effectively reflect the long wavelength infrared radiation, yet provide a high degree of transparency. That percentage which is absorbed by the glass will seldom create a problem due to thermal shock quality of this glass.
Notice the small percentage of radiant heat that is permitted to pass through the RADIANT Brand Heat Shield, per the illustrated chart. Whereas other types of glass, including the heat absorbing, reflect only reflect 4% infrared. RADIANT Brand Heat Shields reflect both radiant and convection heat. This reflective property, termed "heat shield," is a metallic film bonded permanently to the glass surface. Install so that the coated side, as marked, is toward the heat source.
TRANSMISSION PERCENT OF INFRARED RADIATION
SOURCE TEMPERATURE IN DEGREES FAHRENHEIT
1 RADIANT Brand Tempered Heat Shield- Double Glazed (ex. Dual Heat Shield)
2 RADIANT Brand BPS* Tempered Heat Shield – Single glazed 7/32" Thick
3 RADIANT Brand BPS* Temper Glass 3/16" Thick
NOTE: Figures are based on 1/4" thick polished plate glass. Tests conducted scientifically by our laboratory.
This bulletin is provided with the primary steel industry in mind. Along with the other hot metal producers, there are numerous applications of shielding radiant heat. Examples are:
Crane Service - Ladle, slab handling, furnace charging, and other hot metal handling types.
Control Stations & Pulpits - Located physically near furnaces, red hot or molten metal.
Mobile Equipment - Slag & Pot Carriers, Slab Carriers, Forging Manipulators, and Front Loaders near the furnace
Foundries - Can use heat shields to protect hot metal carriers, pouring operators and sand removers.
Furnaces - Have or need viewing windows to reduce heat loss and protect the instruments or operating personnel that are looking inside.
Radiant heat is transmitted through space by wave motion. The intensity and wavelength distribution depends on the nature and temperature of the surface. This heat can only be controlled by insulator screening and not by general ventilation, according to Mr. G. F. Haines, Jr., Mellon Institute. Regular glass cannot properly insulate direct radiation; but reflective glass makes a most efficient transparent screen. This screening of radiation can reduce fatigue and protect against eye injury of personnel and improve work conditions in "hot spots."
By preventing this radiant "sunshine" from striking the operator, you are allowing him to operate at his full efficiency. Solar radiation requires glass other than RADIANT Brand, depending on the total situation.
Double-glazing is suggested for most situations. This is especially true when air conditioning is provided. Many times more air conditioning capacity is required for ordinary double glazed window areas compared to insulated walls, therefore, it is necessary to control the BTU/sq. ft. and direct rays through the glass area. Refrigeration specialists say "that your cooling requirement can be reduced when using heat reflective glass for window areas on high radiant applications." The approach to a heat problem in a radiant environment is substantially different than when ambient air is a major consideration. This includes open control stations, and enclosed cabs and pulpits, without air conditioning .
HEAT SHIELD GLASS PRODUCTS:
RADIANT Brand Tempered Heat Shield Borosilicate is heat resisting, possessing the highest quality heat reflective coating and full temper for thermal shock protection. 7/32” thick, up to 36” x 48”
RADIANT Brand Tempered Heat Shield Safety is a “safe-break” glass with a high quality reflective coating and full temper for safety. 1/4” thick, up to 40-5/16” x 58-5/16”
MACPHERSON Brand BPS Tempered Heat Shield Borosilicate is heat resisting, heat reflecting, thermal shock resisting, and tempered for impact strength - 7/32" thick, up to 34-5/16" x 58-5/16".
MACPHERSON Brand Tempered IRR - Safety Plate Glass is heat resisting, heat reflecting, tempered for strength and "safe break" - 1/4" thick, up to 40-5/16" x 58-5/16".
RADIANT Brand Heat Shield No. 101 Plate - infrared reflecting crystallized glass provides an increase of 900 degrees Fahrenheit in temperature limit over previously available heat shield glass. 3/16" thick, up to 30" x 60"
STANDARD INVENTORY ITEMS:
The RADIANT Brand Dual Heat Shield comes in standard sizes, complete unit...
Dimensions shown are inches of overall unit.
HEAT RESISTANCE of the base material used as a radiant screen is a must, for the energy that is absorbed by the screen becomes heat. The ability of the glass to accept thermal gradient and shock of everyday mill service is the deciding factor in choosing the right glass.
SAFETY is a property of the RADIANT Brand Tempered IRR. Tempering sets the glass surface in high compression, increasing its strength several times. This glass will accept more twisting and flexing than other glasses, which is particularly important for crane and other mobile cab service. Refer to Safe-Plate laminated products for severe impact and molten metal protection.
VISIBILITY is excellent. The coating is "HAZE FREE". The light transmission is 81% for the RADIANT Brand Tempered heat Shield Safety. Tinted (light blue-green) heat shields are furnished in Safety Plate for additional glare reduction, with 54% LT. Only superior quality polished plate glass is used.
METAL SPLASH can be a problem that affects conditions of safety, heat control and service life. No specific recommendation will be offered here, but many steel mill operations have the potential danger of molten metal splashing the glass. Serious injuries to operating personnel have been caused because even double glass proved to be no protection. SAFE-SHIELD* is a highly effective safety shield against molten metal, and furnace and ladle reactions.
MAINTENANCE is minimum with the RADIANT Brand Heat Shield. Cleaning the glass should be accomplished with a soft cloth and cleaning agent, so as not to abrade the glass. As recommended, the glass is suited to the job, and is furnished in frames that protect the glass under severe service conditions. Glass replacement need not be accomplished while holding up productions. A ready framed window may be your spare, and the exchange takes only minutes.
OTHER MACPHERSON BRAND GLASS PRODUCTS:
MACPHERSON Brand BPS* Glass - low expansion heat absorbing heat resisting to 600 degrees Fahrenheit, thermal shock resisting, resistant to abrasion and tempered for strength - 3/16" thick, up to 40-5/16" x 58-5/16".
RADIANT Brand No. 101 Plate - transparent crystallized glass that withstands thermal shock to 1470 degrees Fahrenheit - 1/4" thick.
MULTI-GLASS Safety Glass- penetration resistant product for low heat applications.
SAFE-SHIELD Glass - for moderate to high heat applications
Combinations of heat strengthen and low expansion glass laminated with special interlayers to thickness of 1/2” and 7/8”. Heavier plate available, on request. Usually, the surface facing the impact side, or opposite the operator, is reflective coated. Sizes up to 40-5/16” x 58-5/16”.
COMPARISON OF PROPERTIES CHART
RADIANT BRAND WINDOW FRAMES:
Mounted plate glass – single, double or triple
“While no type of glass can be guaranteed against breakage, such difficulty can largely be avoided by using the right kind of glass properly installed.” We completely agree with this authoritative statement. Taking all service requirements into consideration when choosing the correct glass or combination of glasses for each individual job, and properly mounting and installing the glass to minimize thermal and mechanical stresses in the glass, will reward the user with long service life.
+ Iron Age, May 29, 1952
* Trademark of MacPherson & Company
95 Pelret Industerial Parkway, Berea, OH 44017