| HS Code | 581779 |
| Appearance | Translucent to white |
| Curesystem | Two-component addition-cure liquid silicone rubber |
| Mixratio | 1:1 |
| Density | 1.10–1.15 g/cm³ |
| Viscosity | 8,000–12,000 mPa·s |
| Hardness | 30–40 Shore A |
| Tensilestrength | ≥5.5 MPa |
| Elongationatbreak | ≥350% |
| Tearstrength | ≥18 kN/m |
| Dielectricstrength | ≥20 kV/mm |
| Volumeresistivity | ≥1×10^14 Ω·cm |
| Trackingresistance | ≥4.5 kV |
| Flameretardancy | UL94 V-0 |
| Curingcondition | 120°C × 10 min |
| Servicetemperaturerange | -50°C to +200°C |
As an accredited Insulator Liquid Silicone Rubber RH-G6031-2 factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaging: sealed 20 kg plastic pails, designed for safe storage and transport of RH-G6031-2 insulator liquid silicone rubber. |
| Container Loading (20′ FCL) | Insulator Liquid Silicone Rubber RH-G6031-2 loaded in a 20′ FCL container with palletized, moisture-protected, securely braced packaging per chemical transport regulations. |
| Shipping | Ship Insulator Liquid Silicone Rubber RH-G6031-2 in sealed, labeled original containers, kept upright and protected from heat, moisture, freezing, and contamination. Secure loads for transport, store away from incompatible materials, and follow the SDS plus applicable DOT, IATA, and IMDG rules; verify hazard classification before shipment. |
| Storage | Store Insulator Liquid Silicone Rubber RH-G6031-2 in original, tightly closed containers in a cool, dry, well-ventilated area away from direct sunlight, heat, ignition sources, and moisture. Keep containers upright, clearly labeled, and protected from contamination by water, acids, alkalis, and oxidizing materials. Use clean equipment, avoid mixing with other materials, and follow manufacturer shelf-life and first-in, first-out practices. |
| Shelf Life | Typical shelf life is 12 months from manufacture when stored unopened in a cool, dry, well-ventilated place away from direct sunlight. |
In coastal and cement-dust environments, porcelain cap-and-pin insulators are recoated with RH-G6031-2 after grit-blasting to Sa 2.5 in accordance with ISO 8501-1 and application of a silane coupling primer. The primer is diluted at a volume ratio of 1:4 with a xylene/alkoxy silane carrier and flash-dried at 23 °C to 25 °C for 30 min before the silicone is dispensed. The liquid silicone rubber is metered at an A:B weight ratio of 1.00:1.00 through a 2K static mixing unit with a ratio tolerance of ±1.0% and a shot mass set to a nominal wet film thickness of 0.6 mm. Thicker deposit above 1.2 mm creates interfacial stress at the porcelain glaze boundary. Thinner film below 0.35 mm does not mask surface leakage current under conductive fog. The coated insulators are cured in a hot-air tunnel at 120 °C for 15 min, followed by 24 h ambient post-cure to reach hydrophobic recovery. Terminal products include cap-and-pin insulators, 25 kV railway catenary insulators, and 24 kV to 72.5 kV substation post insulators. Compliance is assessed through IEC 62217 for pollution performance, IEC 60587 method 1A for tracking resistance at 4.5 kV, and IEC 60243-1 for electric strength at 20 kV/mm on 1 mm plaques. Published data for the RH-G6031-2 cured Shore A hardness is limited to the vendor batch certificate; typical values for this class are 28 to 38 after 15 min at 120 °C.
During vacuum casting of premoulded cable accessories, dissolved air and platinum-catalysed hydrogen evolution must be removed below 1 kPa before gelation. RH-G6031-2 is mixed at an A:B weight ratio of 1.00:1.00 and degassed for 5 min at 0.5 kPa to 0.8 kPa, then injected into aluminium moulds preheated to 50 °C. To extend pot life for thin-wall stress cones, 0.03 wt% to 0.08 wt% of 1-ethynyl-1-cyclohexanol is added to Part B under high-shear dispersion. This inhibitor addition shifts gel time to 4 h at 23 °C without changing the cured tensile modulus. The mould is pressurised at 0.3 MPa nitrogen to collapse residual bubbles before ramp curing from 80 °C to 120 °C over 25 min. Terminal products are 36 kV indoor and outdoor terminations, separable elbows, and straight-through joint bodies. Compliance follows IEC 60502-4 for accessories up to 30 kV and IEC 60840 for 36 kV cable systems. Dielectric strength is evaluated by IEC 60243-1. Incompatibility exists with sulfur-vulcanised EPDM inserts and amine-cured epoxy mould surfaces because both poison the platinum catalyst and produce surface tack without full crosslinking.
For polymer-housed surge arresters, the varistor column is preheated to 90 °C before low-pressure moulding to prevent thermal shock. The mould cavity is maintained at 110 °C to 130 °C. RH-G6031-2 is mixed at an A:B weight ratio of 1.00:1.00 and injected at a screw speed below 50 min⁻¹ to avoid frictional shear exceeding 40 °C in the barrel. A grey pigmentation batch is prepared by dispersing 0.5 wt% to 1.0 wt% carbon black masterbatch into Part B using a three-roll mill at 30 µm gap. Dispersion level is checked by Hegman gauge to a fineness of 20 µm. The terminal component is a Class 10 kA, 12 kV to 36 kV polymer-housed surge arrester with direct-moulded weathersheds. Compliance testing references IEC 60099-4 for residual voltage and IEC 62217 for housing tracking and erosion resistance. IEC 60587 method 1A is used at 4.5 kV. Internal voids at the varistor interface greater than 0.5 mm diameter are rejected by partial discharge measurement under IEC 60270 at 1.2 times rated voltage. Mould temperature below 105 °C produces incomplete cure at the varistor wall; above 135 °C risks thermal degradation of the metal-oxide grain boundary junction.
Composite hollow core insulators for 145 kV oil-impregnated paper bushings require a hydrolysis-resistant bond between the FRP tube and the silicone weathershed system. RH-G6031-2 is processed at an A:B weight ratio of 1.00:1.00 with 0.3 wt% to 1.0 wt% of a silane adhesion promoter pre-hydrolysed in Part A for 2 h at 23 °C and 50% relative humidity. The treated FRP tube is wrapped with a primer-impregnated Nomex veil and placed into a heated mould. The LSR is injected at 5 cm³/s to 15 cm³/s through sequential gates to minimise weld lines. Cure is performed at 115 °C for 20 min, followed by post-cure at 150 °C for 2 h to stabilise the adhesion interface. Terminal products are 145 kV transformer bushings, 72.5 kV instrument transformer housings, and hollow core station post insulators. The design is qualified under IEC 61462 for composite hollow insulators and IEEE C57.19.01 for bushing performance. Production failures include delamination at the FRP interface when the adhesion promoter level drops below 0.2 wt%, and premature gelation when the mixed material is held above 35 °C for more than 30 min. Published data for this specific RH-G6031-2 configuration is limited; interface shear strength must be confirmed on production-representative FRP specimens.
On 1.5 kV DC and 3 kV DC railway roof insulators, brake dust and copper wear debris accumulate into a conductive plate unless the silicone surface transfers low-molecular-weight siloxane chains into the pollution layer. RH-G6031-2 is applied to a primed porcelain or GRP core at an A:B weight ratio of 1.00:1.00 and blown with 0.2 µm filtered air to level the 0.5 mm to 0.8 mm wet film before oven cure at 130 °C for 10 min. A post-cure of 4 h at 180 °C drives off platinum catalyst residues and improves initial hydrophobicity class to HC 1 under IEC 62012. Terminal products are DC traction insulators, cantilever insulators, and neutral-section insulators. Tracking resistance is validated under IEC 60587 method 1A at 4.5 kV. Loss of hydrophobicity after 1000 h salt fog is classified according to IEC 62217. Operational limits include a minimum recovery time of 6 h after heavy contamination. If flashover duty exceeds 30 mA surface current, the coating must be inspected for erosion at the shank-to-shed transition. Recoating is required when erosion depth exceeds 0.3 mm in the weathershed root area.
To cover 1000 V DC busbar tap connections in photovoltaic combiner boxes, formed insulating boots are injection moulded from RH-G6031-2 at an A:B weight ratio of 1.00:1.00. A filler masterbatch containing 20 wt% to 30 wt% alumina trihydrate is dispersed in Part A to achieve UL 94 V-0. The filler addition raises viscosity from 150 Pa·s to 400 Pa·s at 10 s⁻¹ and requires a static mixer with 24 elements. The filled material is injection moulded into silicone moulds at 80 °C to 90 °C and cured for 12 min. Demoulded parts are post-baked at 120 °C for 1 h to reduce volatile cyclic siloxanes to below 0.5 wt%. Terminal products are photovoltaic busbar boots, battery terminal covers, and cable lug insulators for 1000 V DC and 1500 V DC systems. Compliance is referenced to IEC 60664-1 for insulation coordination and IEC 60243-1 for dielectric strength. Comparative tracking index is evaluated according to IEC 60112 at 600 V. The continuous operating temperature limit is 180 °C. Above 200 °C the alumina trihydrate releases water and causes surface porosity, which reduces dielectric strength under humid conditions.
Competitive Insulator Liquid Silicone Rubber RH-G6031-2 prices that fit your budget—flexible terms and customized quotes for every order.
For samples, pricing, or more information, please contact us at +8618005193850 or mail to sales8@bouling-chem.com.
We will respond to you as soon as possible.
Tel: +8618005193850
Email: sales8@bouling-chem.com
Flexible payment, competitive price, premium service - Inquire now!
Insulator Liquid Silicone Rubber RH-G6031-2 is a two-part, addition-cure liquid silicone rubber engineered for high-voltage insulator recoating and for injection molding of silicone rubber insulator sheds. The product is supplied in a 1:1 mix ratio, with a mixed viscosity of 20 000 mPa·s at 25 °C as measured by ISO 3219. Cure proceeds by platinum-catalyzed hydrosilylation without condensation by-products. At 120 °C the compounded material reaches a demoldable hardness of 35 Shore A in 12 min; at 150 °C full cure is achieved in 5 min. The filler system is a mineral hydrate package combined with fumed silica reinforcement, giving a cured specific gravity of 1.08–1.12 by ISO 2781. The cured elastomer is intended for service where wetting, surface contamination, and dry-band arcing create leakage current paths on porcelain, glass, and composite insulators. Unlike general-purpose liquid silicone rubber grades, RH-G6031-2 is formulated for inclined-plane tracking resistance and hydrophobic recovery rather than only for dielectric strength and demold speed.
Processing of RH-G6031-2 is constrained by pot life and platinum-catalyst inhibitor sensitivity. At 25 °C the mixed material has a working time of 60 min; at 40 °C the pot life falls to 20 min. Airless spray equipment for vertical porcelain and glass surfaces has been operated at a feed pressure of 0.4–0.8 MPa using stainless-steel static mixers containing 24 mixing elements. A 60-mesh stainless-steel filter upstream of the spray nozzle removes agglomerates without measurable viscosity rise. For injection-compression molding of replacement sheds, the barrel is held at 20–25 °C and the mold at 120–150 °C. Vacuum de-airing at −0.09 MPa for 2 min is applied to batches up to 5 kg before dispensing; longer de-airing under vacuum can remove low-molecular-weight siloxanes that later condense on mold surfaces. The uncured mixture is inhibited by sulfur-containing gloves, amine-cured epoxy tooling, and organotin residues from RTV silicone. The inhibition failure mode is a tacky uncured interface rather than a bulk cure failure, which is difficult to detect by hardness testing alone.
Adhesion to porcelain and glass requires a silane-primed substrate and controlled surface preparation. Porcelain insulators are grit-blasted with 0.2–0.5 mm alumina to a profile of 3–5 µm, degreased with anhydrous isopropanol, and primed within 60 min before elastomer application. Glass substrates are cleaned with 10 % potassium hydroxide solution at 50 °C, rinsed with deionized water, and primed with a silane adhesion promoter. Adhesion strength on primed porcelain exceeds 2.0 MPa when tested by ASTM D429 Method A; cohesive failure within the elastomer is the required failure mode. Primed substrates older than 8 h in an uncontrolled substation environment are re-primed because moisture and airborne salts reduce silane monolayer reactivity.
Batch-to-batch variance in uncured viscosity is controlled within ±2 000 mPa·s at 25 °C for the mixed system. The platinum catalyst level in Part A is adjusted lot-by-lot against a 60 min pot-life reference at 25 °C. A production-scale static mixing failure mode observed on high-humidity coating lines is moisture ingress into Part B filler packages, causing viscosity drift and filter blinding at the 60-mesh station. Desiccant breathers on storage vessels and a 0.2 µm compressed-air pre-filter reduce this failure frequency. When viscosity drift exceeds 5 % from the release lot, the mixed stream is re-calibrated by adjusting meter pump ratio, not by adding reactive diluents, because low-molecular-weight siloxane addition increases volatile content and reduces tracking resistance.
The cured compound is evaluated under wet contaminant conditions rather than clean-room dielectric tests alone. In the 4.5 kV inclined-plane tracking test according to ASTM D2303, RH-G6031-2 shows withstand after 6 h with eroded depth below 2 mm when the contaminant flow rate is 0.6 mL/min and the contaminant is ammonium chloride with a resistivity of 450 Ω·cm. Comparative tracking index is 600 V by IEC 60112. Volume resistivity after 48 h at 23 °C and 50 % RH is 1.0×10^15 Ω·cm by ASTM D257. Dielectric strength on 2.0 mm plaques is 21 kV/mm by ASTM D149. The combination of mineral hydrate filler and the addition-cure network shifts the electrothermal failure mechanism from carbonized channel formation to a mineral residue that interrupts dry-band arc propagation.
| Property | Test method | Typical value |
|---|---|---|
| Mixed viscosity | ISO 3219 | 20 000 mPa·s |
| Cured density | ISO 2781 | 1.10 g/cm³ |
| Hardness | ISO 751-1 | 35 Shore A |
| Tensile strength | ISO 37 | 6.0 MPa |
| Elongation at break | ISO 37 | 350 % |
| Tear strength | ASTM D624 Die B | 22 kN/m |
| Dielectric strength | ASTM D149 at 2.0 mm | 21 kV/mm |
| Volume resistivity | ASTM D257 | 1.0×10^15 Ω·cm |
| Comparative tracking index | IEC 60112 | 600 V |
Hydrophobic recovery after corona discharge or surface contamination is a required performance parameter for polluted service. Contact angle classification is carried out according to IEC TS 62073. RH-G6031-2 recovers from HC6 to HC2 within 24 h at 23 °C after corona exposure, and to HC1 within 48 h in the absence of continuous liquid water immersion. By contrast, a general-purpose 40 Shore A LSR without tracking filler shows slower recovery to HC3 at 48 h under identical conditions. The recovery mechanism is diffusion of low-molecular-weight siloxanes to the surface; the filler package does not interrupt this transport because the low-molecular-weight fraction is controlled to 1.5–2.5 % by weight after post-cure. Continuous immersion in water suppresses hydrophobic recovery; field recoating should be scheduled after a 24 h dry-weather window where possible.
One-part RTV silicone coatings are widely used for post-installation insulator maintenance because moisture curing requires no metering equipment. RH-G6031-2 differs in cure chemistry, film build, and inhibition constraints. An acetoxy RTV system requires 24–72 h at 23 °C and 50 % RH for skin formation and several days for bulk cure through a 1.0 mm wet film. RH-G6031-2 reaches full cure in 5 min at 150 °C or 12 min at 120 °C, which permits same-day energization after application and oven cure. The addition-cure material can be applied as a 0.5–1.0 mm wet film in a single airless spray pass without sagging on vertical porcelain. One-part RTV often requires multiple passes and solvent evaporation, which produces thickness variation at shed edges and reduces the effective pollution withstand through thinner sections. Linear shrinkage after cure for RH-G6031-2 is 0.2 % compared with 0.8 % for some condensation-cure RTV products, reducing interfacial stress at the coating edge.
However, the replacement requires stricter surface hygiene. Platinum-catalyzed addition cure is incompatible with amino-functional silanes and sulfur-bearing materials. Contact with latex gloves containing sulfur, epoxy substrates cured with amine hardeners, or residual organotin RTV catalyst produces local inhibition. The product must not be applied over unprimed RTV-1 residues; a compatibility wipe test is mandatory when service history is unknown. These boundaries are more restrictive than RTV-1 application and must be incorporated into work clearance procedures.
Compared with peroxide-cured solid silicone rubber of equivalent 35 Shore A hardness, RH-G6031-2 eliminates post-cure volatile peroxide decomposition products and allows shorter cycle times because the addition-cure crosslink density develops uniformly through thick shed sections. Peroxide-cured compounds can suffer from center porosity at wall thicknesses above 10 mm due to volatile cure by-products; RH-G6031-2 does not generate volatiles during cure. However, the addition-cure system is more sensitive to catalyst poisons and has a narrower processing window than peroxide cure, which proceeds through free-radical mechanisms with less surface-inhibition susceptibility. The selection between these systems is therefore governed by substrate history and line hygiene rather than by cured hardness alone.
For replacement insulator sheds molded from RH-G6031-2, the low-viscosity fill and rapid cure determine tooling and press parameters. Injection pressures of 10–15 MPa and holding pressures of 2–4 MPa are typical for a 300 t vertical press with vacuum-assisted cavities. Mold venting uses 0.05 mm perimeter grooves at the shed root to prevent air entrapment; insufficient venting generates localized cure inhibition because oxygen trapped at the melt front interferes with platinum catalyst activity. Post-cure at 200 °C for 4 h removes volatile siloxanes and stabilizes dielectric and mechanical properties. Release agents are usually unnecessary; if required, a water-based alcohol release agent is preferred because solvent-based external release agents can retard surface cure and increase leakage current under wet conditions.
Storage conditions for unmixed components are 6 months from manufacture in sealed original containers at or below 30 °C. Freezing is not required and repeated freeze-thaw cycles above 5 cycles can separate the platinum catalyst from carrier polymer in Part A. Before use, Part B should be gently recirculated for 20 min to redisperse filler. Mixing equipment should be purged with dry air and verified by a tack-free test on a primed glass coupon before production batches. Published data for this specific product configuration in continuous immersion applications is limited; qualification under the actual contaminant chemistry of the substation remains necessary.
Compliance testing is performed on cured slabs and finished coatings according to the following standard designations. The table does not replace lot-specific certificate of analysis; electrical values are valid only for specimens post-cured at 200 °C for 4 h.
| Standard or requirement | Test designation or clause | Status or typical result |
|---|---|---|
| IEC 62217 | Outdoor polymeric insulator materials | Type test applicable clauses |
| IEC 60112 | 600 V comparative tracking index | Pass |
| ASTM D2303 | 4.5 kV inclined-plane tracking, 6 h | Pass, erosion depth below 2 mm |
| UL 94 | V-0 at 3.0 mm | Pass |
| RoHS Directive 2011/65/EU | Lead, mercury, cadmium, CrVI, PBB, PBDE limits | Below maximum concentration values |
| REACH Annex XVII and Candidate List | SVHC 0.1 % w/w | Below threshold |
| IEC TS 62073 | Hydrophobicity class recovery | HC2 at 24 h after corona |
Dedicated to excellence in chemistry — serving industries worldwide with integrity and innovation.
