Disclaimer: The key technical parameters in this article are derived from the official technical documents of Ningjin APC Industries, a tier-one UL/FM fire protection valve manufacturer in China (serving as actual production references for Ningjin APC Industries factory fire valves and for customers to understand product usage; please consult our professional engineering team for specific inquiries).
1. Technical Datasheet Overview & Made-to-Order Production
Piping engineers, CAD designers, and procurement specialists reviewing the GD-381G Worm Gear Grooved Valve Specification PDF can verify exact structural tolerances, flow characteristics, and metallurgy for manual grooved end butterfly valves. Unlike the supervised GD-381X series, the GD-381G is equipped with a standard non-signal worm gear operator, making it ideal for fire water isolation points, pump room suction/discharge manifolds, and drain headers where electrical supervisory switch monitoring is not specified.
Ningjin APC Industries manufactures the GD-381G strictly on a **made-to-order** basis rather than holding pre-built stock, ensuring each production lot aligns with exact customer groove standards, protective coatings, and regional compliance requirements.
2. Core Technical & Hydraulic Specifications
The engineering parameters established in the official GD-381G Worm Gear Grooved Valve Specification PDF guarantee dependable performance across indoor and outdoor fire networks:
- Maximum Working Pressure: 300 PSI (2.1 MPa) continuous rating
- Maximum Testing Pressure: 600 PSI hydrostatic shell and seat factory test
- Structural & Pressure Compliance: Designed in accordance with UL 1091, ULC/ORD-C1091, and FM 1112 pressure performance criteria
- Groove End Standards: ANSI/AWWA C606 or metric standard clear waterway design for minimal head loss
- Working Temperature Range: 0 ~ 80°C (32 ~ 176°F)
- Top Flange & Certifications: ISO 5211 top mounting flange; CE certified, with optional NSF/ANSI 61 & NSF/ANSI 372 lead-free compliance available upon request
- Available Nominal Sizes: 2", 2½", 3", 4", 5", 6", 8", 10", and 12"
3. Worm Gear Operator & Reduction Ratio Matrix
To deliver smooth manual torque control and eliminate sudden valve slam (water hammer) in pressurized fire mains, the GD-381G Worm Gear Grooved Valve Specification PDF specifies precision gear reduction ratios paired with ergonomic handwheels:
| Nominal Valve Size | Gear Reduction Ratio | Handwheel Diameter (ΦD) | Operator Configuration |
|---|---|---|---|
| 2" – 5" | 24:1 | 152 mm | Standard Manual Worm Gearbox (Non-Signal) |
| 6" | 24:1 | 200 mm | Standard Manual Worm Gearbox (Non-Signal) |
| 8" – 10" | 30:1 | 300 mm | Standard Manual Worm Gearbox (Non-Signal) |
| 12" | 80:1 | 350 mm | Standard Manual Worm Gearbox (Non-Signal) |
4. Component Bill of Materials (BOM)
The metallurgy outlined in the GD-381G Worm Gear Grooved Valve Specification PDF ensures resistance to internal water corrosion and stem binding:
| No. | Component Description | Material Specification |
|---|---|---|
| 1 | Upper Shaft Sealing Nut | WCB |
| 2 | Shaft Seal | EPDM |
| 3 | Body | Ductile Iron |
| 4 | Upper Shaft | 416 Stainless Steel |
| 5 | Disc + Rubber Seat | Ductile Iron + EPDM Encapsulated |
| 6 | Lower Shaft | 416 Stainless Steel |
| 7 | Lower Shaft Sealing Nut | WCB |
| 8 | Stem Bushing | PTFE / C95400 |
| 9 | O-Ring | EPDM |
| 10 | Gear Box | Ductile Iron Assembly |
5. Frequently Asked Questions (FAQ)
The GD-381G is designed for indoor and outdoor fire water supply lines, drain piping, high-rise fire systems, and industrial plant fire networks requiring manual worm gear operation (without electrical tamper switches) at up to 300 PSI and 0 to 80°C.
It conforms to UL 1091, ULC/ORD-C1091, and FM 1112 pressure performance criteria (300 PSI working / 600 PSI test) and carries CE approval alongside optional NSF/ANSI 61 & 372 lead-free certification.
Yes. Its AWWA C606 clear waterway grooved ends, 300 PSI rating, 416 stainless steel shafts, and ISO 5211 top flange match leading Western grooved butterfly valves.
It adheres to North American AWWA C606 grooved standards, metric grooved piping dimensions, and international ISO 5211 actuator mounting rules.
The standard warranty period is generally 18 months. Please confirm specific project terms with your sales representative.
No off-the-shelf inventory is stocked; all units are made-to-order with a 6 to 9 week production lead time. Contact our technical sales team via email to request the complete dimensional PDF drawing package.
