Product Overview
The BDM-VII/D Series Double Compression Explosion-Proof Cable Gland is a high-performance, heavy-duty fitting engineered specifically for terminating and securing armored cables in hazardous industrial environments. Featuring a dual-seal structure with a central armor clamping cone, this cable gland seals both the inner sheath (after armor stripping) and the outer jacket, providing ultimate flameproof security and environmental sealing.
Precision-machined from premium nickel-plated brass and fitted with high-grade silicone rubber seals, the BDM-VII/D series delivers an IP66 ingress protection rating and an extraordinary operating temperature range of -60°C to +100°C. Fully certified under Ex db IIC Gb / Ex eb IIC Gb / Ex tb IIIC Db explosion-proof standards, it is trusted across offshore platforms, oil refineries, chemical facilities, and military projects.
Key Features
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Double Compression Sealing System: Equipped with dual silicone rubber seals. The inner seal clamps tightly onto the inner cable jacket after armor stripping, while the outer seal grips the external sheath, ensuring complete gas and moisture isolation.
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Integrated Armor Clamping Cone: Designed with a precision metal armor cone and lockring assembly that firmly grips steel wire armor (SWA), steel tape armor (STA), and braid-armored cables, delivering superior pull-out resistance and mechanical ground continuity.
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Dual-Certified Hazardous Area Protection: Fully compliant with Ex db (flameproof), Ex eb (increased safety), and Ex tb (dust ignition proof) standards for Ex db IIC Gb / Ex eb IIC Gb / Ex tb IIIC Db.
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Wide Temperature Silicone Rubber Seal: High-performance silicone seals retain elastic memory and airtight integrity in extreme temperatures from -60°C to +100°C, preventing seal hardening or cracking.
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IP66 Weatherproof & Dustproof Protection: Outfitted with durable seal rings and entry thread O-rings to protect sensitive electrical equipment against severe marine weather, high-pressure water washdowns, and combustible dusts.
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Corrosion-Resistant Material Options: Manufactured from nickel-plated brass for superior salt-spray and oxidation resistance, with optional 304 or 316 Stainless Steel bodies available upon request.
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Global Standard Threading: Available in standard Metric (M), NPT, and G (PF) pipe threads to suit diverse international junction boxes and enclosures.
Applications & Scope of Use
engineered for severe industrial environments and hazardous cable wiring installations:
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Explosive Gas Atmospheres: Certified for Zone 1 and Zone 2 hazardous areas (Gas Groups IIA, IIB, and IIC).
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Combustible Dust Atmospheres: Suitable for Zone 20, Zone 21, and Zone 22 dust hazards.
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Compatible Cable Types: Specifically designed for all armored braid, steel wire (SWA), and steel tape (STA) armored cables.
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Heavy Industrial Sectors: Oil & gas extraction, petroleum refining, chemical processing, military & defense depots, offshore vessels, and food & pharmaceutical cleanroom facilities.
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Enclosure Connections: Flameproof terminations into Ex d / Ex e control cabinets, junction boxes, motors, and field terminal stations.
Technical Specifications
| Parameter | Specification Details |
| Product Model | BDM-VII/D Series |
| Explosion-Proof Marking | Ex db IIC Gb / Ex eb IIC Gb / Ex tb IIIC Db |
| Protection Rating | IP66 Waterproof & Dustproof |
| Operating Temperature | -60°C to +100°C |
| Flammability Rating | UL94 V-0 |
| Standard Material | Nickel-Plated Brass (304 / 316 Stainless Steel optional) |
| Sealing Element Material | Corrosion-Resistant Silicone Rubber |
| Target Cable Types | All Armored Cables (Steel Wire / Steel Tape / Braid Armored) |
| Interface Threads | Metric (M), NPT Pipe Thread, G Pipe Thread |
| Execution Standards | IEC60079-0, IEC60079-7, IEC61241-0, IEC61241-1, EN60079-0, EN60079-7, EN61241-0, EN61241-1, GB3836.1, GB3836.3, GB12476.1, GB12476.5 |
Product FAQ
Q1: What is the difference between a single compression and a double compression cable gland?
A single compression gland only seals the outer jacket of the cable. A double compression gland (like the BDM-VII/D) seals both the inner cable jacket (under the armor) and the outer jacket, while securely clamping the armor wire/tape in the middle. This provides superior explosion-proof containment and double environmental sealing against ingress.
Q2: What types of armored cables can be installed with the BDM-VII/D cable gland?
The BDM-VII/D series features a universal armor clamping cone assembly suitable for virtually all armored cable types, including Steel Wire Armored (SWA), Steel Tape Armored (STA), and Wire Braid Armored (SWB) cables.
Q3: How does the silicone seal perform in extremely cold or hot environments?
Our engineered silicone rubber seals remain flexible and maintain constant sealing pressure across temperatures ranging from -60°C up to +100°C. Unlike standard rubber or neoprene seals, silicone will not become brittle in arctic cold or lose elasticity under high operating heat.
Q4: Are NPT threads and extended thread lengths available for thick cast-iron boxes?
Yes. Standard threads include Metric, NPT, and G threads. As a direct manufacturer, we offer custom thread machining—including custom thread lengths, pitches, and thread conversions—to accommodate thick-walled cast enclosures and specialized bulkheads.
Q5: Can I order this cable gland in Stainless Steel?
While Nickel-Plated Brass is our standard material due to its cost efficiency and excellent corrosion resistance, we also manufacture the BDM-VII/D series in 304 and 316 Stainless Steel for highly aggressive marine or acidic chemical processing environments.
