“Glass coating” sounds like one job until the actual requirement turns out to be color-coding a batch of quartz tubes, protecting a graphite electrode from oxidizing, releasing a casting cleanly from a mold, or patching a cracked exhaust manifold before the shift ends. Incure’s Epo-Weld™ high temperature glass coating line covers all four across twenty-six grades, organized by what the coating actually has to do rather than by a single shared temperature rating.
Ten Color-Coded Grades Are One Marking System, Not Ten Formulations
HTC-6006, 6007, 6013, 6022, 6031, 6059, 6060, 6068, 6069, and 6070 share nearly identical mechanics — Shore D85 hardness, 11,500 PSI flexural strength, 2,300 PSI tensile shear, and a 24-hour room-temperature cure — differing mainly by pigment and opacity rather than chemistry. Brown-black HTC-6006 and jet-black HTC-6013 mark and light-block quartz and glass components; cobalt-blue HTC-6022, gray HTC-6031, light-green HTC-6059, and dark-green HTC-6060 exist purely for color-coded identification and inventory tracking on lighting fixtures, laboratory glassware, and semiconductor process tubes; matte-silver HTC-6068 and off-white HTC-6069 are chosen for reflectivity rather than marking, directing radiant heat back through a reflector lamp or heater tube instead of absorbing it. HTC-6007 is simply HTC-6006’s high-viscosity version, built for thicker film builds where more opacity or gap-filling is needed. HTC-6070 is the one true outlier in the group — a glass-ceramic-filled formulation at D82 hardness and 8,000 PSI flexural, rated to 1600°F rather than the family’s usual 1500–2000°F, purpose-built for maximum reflectivity on infrared heaters and UV curing lamps.
Refractory and Furnace Protection
HTC-303 and HTC-383 both protect graphite from oxidation, using different fillers to get there — HTC-303’s titanium diboride ceramic holds to 2000°F, while HTC-383’s silicon carbide adds high hardness against erosion on graphite electrodes and susceptors. HTC-329, HTC-330, and HTC-338 all seal porous refractory fiber and brick against dusting and particulate contamination, differing mainly in viscosity: HTC-329 is phosphate-bonded for abrasion resistance on brick linings, HTC-330 targets fiber modules and launder systems up to 2300°F, and HTC-338 is the low-viscosity version built to penetrate and impregnate fiber surfaces by spraying or brushing rather than troweling. HTC-309 seals and protects alumina fiberboard against dusting in sensitive furnace-lining applications. At the extreme end, HTC-389’s yttrium oxide chemistry stays chemically inert against reactive metals like titanium and uranium during aerospace-metallurgy crucible melting, while HTC-390’s zirconium oxide coating holds oxidation resistance up to 3270°F on carbon steel and refractory metals in chemical processing.
Release Coatings for Metal Casting
HTC-347 and HTC-365 are both boron nitride release coatings that keep molten non-ferrous metal from wetting a mold surface, but serve opposite maintenance philosophies: HTC-347 is a hard, durable coat meant to last across many casting cycles, while HTC-365 is a soft, consumable coat reapplied each cycle or as needed on hot-top rings and transition plates. HTC-374 takes a different approach entirely — a pure graphite lubricant that replaces oil-based release agents on glass-forming molds and wire-drawing dies, working in reducing and neutral atmospheres where the other two grades aren’t specified.
Email Us with your substrate, service temperature, and whether you need marking, sealing, release, or repair, and Incure’s engineers can confirm which Epo-Weld™ glass coating grade actually fits.
Repair Putties for Emergency and Vertical Maintenance
HTCP-550, HTCP-650, HTCP-750, and HTCP-950 are all water-based, air-curing repair compounds built to replace a welded patch, but they split by service temperature and orientation. HTCP-550 fills cracks and voids in cast iron and stainless steel manifolds and exhaust stacks up to 2000°F. HTCP-650 is a pliable, conformable gasket seal rated to 2350°F — the highest ceiling in the repair group — for boiler doors and molten metal troughs that need a removable rather than permanent seal. HTCP-750 is a two-part, aluminum-filled putty for machinable casting repair, but tops out lower at 1400°F. HTCP-950 is the non-sagging formulation of the group, explicitly engineered to stay in place on vertical and overhead surfaces during cure for burner manifolds, exhaust ducting, and incinerator walls up to 2000°F, where a runnier repair compound would slump before it set.
Conductive Coatings for EMI Shielding and Grounding
HTCA-152 and HTCA-154 both use nickel filler for electrical conductivity at a comparatively modest 1000°F ceiling, offering magnetic and electrical shielding as a lower-cost alternative to silver-filled adhesives. The difference is viscosity and form: HTCA-152 is a thixotropic paste for grounding and shielding bonds, while HTCA-154 is a flowable liquid coating applied to ceramic enclosures and high-temperature connectors where a thin, even shield layer matters more than gap-filling.
Where the Line Fits
Lighting and quartz-component manufacturers standardize on the color-coded marking family for batch tracking and light management without treating ten separate colors as ten separate qualification decisions. Furnace and refractory maintenance programs pull from the protection and repair groups together — sealing fiber and brick with the refractory coatings, then patching structural damage with the HTCP putties, the same weld-replacement approach covered for metal components in Incure’s high strength structural epoxy line. Foundries and glass-forming operations rely on the boron nitride and graphite release coatings to keep production moving between casting or forming cycles. Facilities already running Incure’s high temperature bonding adhesive line for ceramic and sensor bonding can add these coatings to the same high-temperature process line for surface protection, marking, and release rather than structural bonding.
Contact Our Team to confirm the Epo-Weld™ glass coating grade for your substrate and function.
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