Single-Acting Spring Return Hydraulic Actuated Surface Safety Valve (SSV)
Description
TECHNICAL DATA SHEET
Product: Single-Acting Spring Return Hydraulic Actuated Surface Safety Valve (SSV)
Standard: API 6A
Pressure Classes: 10,000 psi (10K) & 15,000 psi (15K)
1. GENERAL SPECIFICATIONS
| Parameter | Specification |
|---|---|
| Product Name | Surface Safety Valve (SSV) |
| Valve Type | API 6A Gate Valve, Single Acting, Spring Return |
| Design Standard | API 6A / ISO 10423 (Latest Edition) |
| Pressure Rating | 10,000 psi (69.0 MPa) / 15,000 psi (103.4 MPa) |
| Actuation Method | Hydraulic Actuated (Single-Acting), Spring Return |
| Fail-Safe Position | Fail-Safe Closed (Hydraulic Open / Spring Close) |
| Product Specification Level | PSL 3 / PSL 4 (Standard for 10K & 15K) |
| Performance Requirement | PR 1 / PR 2 (PR 2 for critical service) |
| Temperature Class | P-U (-29°C to 121°C) or L-U (-46°C to 121°C) |
| Material Class | DD / EE (Standard) or FF / HH (Sour Service) |
| End Connection | API 6A Flanged (Studded or Blind) |
2. DESIGN & MANUFACTURING STANDARDS
| Standard | Description |
|---|---|
| Primary Design | API 6A / ISO 10423 |
| Material Specification | NACE MR0175 / ISO 15156 (Sour Service) |
| Flange Dimensions | API 6A (Standard or Studded) |
| Testing | API 6A Annex F (PR2), API 598 |
| Quality System | ISO 9001, API Q1 |
| Traceability | EN 10204 3.1 / 3.2 |
3. MATERIALS OF CONSTRUCTION
Standard configuration for 10K / 15K wellhead service. Materials may vary based on specific bore size and fluid composition.
| Component | Standard Material (10K) | Standard Material (15K) |
|---|---|---|
| Body / Bonnet | ASTM A182 F22 (Alloy Steel) | ASTM A182 F22 / F91 |
| Stem | 17-4 PH Stainless Steel | Inconel 718 / 17-4 PH |
| Gate / Seat | Metal-to-Metal (Tungsten Carbide) | Metal-to-Metal (Tungsten Carbide) |
| Seals / O-Rings | Viton / HNBR / PTFE | Viton / HNBR / PTFE |
| Spring | Inconel X-750 / Elgiloy | Inconel X-750 / Elgiloy |
| Actuator Housing | Carbon Steel / Alloy Steel | Carbon Steel / Alloy Steel |
| Hydraulic Ports | Stainless Steel (316SS) | Stainless Steel (316SS) |
4. TECHNICAL PARAMETERS
| Parameter | 10K Specification | 15K Specification |
|---|---|---|
| Working Pressure | 10,000 psi (69.0 MPa) | 15,000 psi (103.4 MPa) |
| Hydrostatic Shell Test | 15,000 psi (103.4 MPa) | 22,500 psi (155.1 MPa) |
| Seat Leakage Test | API 6A Annex F / API 598 | API 6A Annex F / API 598 |
| Hydraulic Supply Pressure | 1,500 – 3,000 psi (10.3 – 20.7 MPa) | 1,500 – 3,000 psi (10.3 – 20.7 MPa) |
| Operating Temperature | -29°C to 121°C (-20°F to 250°F) | -29°C to 121°C (-20°F to 250°F) |
| Actuation Type | Single-Acting Hydraulic | Single-Acting Hydraulic |
| Fail-Safe Action | Spring Return (Close on Loss of Pressure) | Spring Return (Close on Loss of Pressure) |
| Bore Size Range | 2 1/16″ to 7 1/16″ (Customizable) | 2 1/16″ to 7 1/16″ (Customizable) |
5. DESIGN FEATURES
Single-Acting Hydraulic Actuator
The actuator utilizes hydraulic pressure to compress the spring and open the valve. Hydraulic fluid is applied to only one side of the piston. When the hydraulic pressure is released (e.g., via an Emergency Shutdown signal), the mechanical spring immediately forces the valve to the closed position.
Fail-Safe Closed (Spring Return)
The valve is designed to fail safe. In the event of a loss of hydraulic supply pressure, hydraulic line rupture, or power failure to the control panel, the stored energy in the spring automatically closes the valve, isolating the wellhead or flowline.
Hydraulic Override & Manual Pump
A manual hydraulic hand pump can be integrated into the control system to allow for local manual operation (opening) of the valve during maintenance or emergency situations when the main hydraulic supply is unavailable.
Balanced Stem Design
The stem incorporates a balance area to counteract the upward force generated by wellbore pressure. This design significantly reduces the hydraulic pressure required to open the valve at 10K and 15K ratings, allowing for a smaller, more efficient actuator.
Metal-to-Metal Sealing
The gate and seat utilize a metal-to-metal seal with tungsten carbide hard facing, ensuring durability, fire safety, and reliable sealing in high-pressure, high-temperature (HPHT) environments.
Anti-Blowout Stem & Backseat
The stem is designed to prevent ejection under pressure. A backseat feature allows for stem packing replacement while the valve is under line pressure.
Automatic Cavity Pressure Relief
Internal design prevents over-pressurization of the body cavity by automatically relieving excess pressure to the upstream side.
6. TESTING & CERTIFICATION
| Test | Standard |
|---|---|
| Shell Test | API 6A Annex F (1.5× Rated Working Pressure) |
| Seat Test | API 6A Annex F (1.1× Rated Working Pressure) |
| Gas Test | API 6A Annex F (Optional) |
| Cycle Test | API 6A PR2 (Optional) |
| Material Cert | EN 10204 3.1 / 3.2 |
| NACE Compliance | NACE MR0175 / ISO 15156 (Optional) |
7. APPLICATIONS
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Oil and gas wellhead Christmas trees
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High-pressure manifolds and flowlines
-
Emergency Shutdown (ESD) systems
-
Sour service (H₂S) and CO₂ injection wells
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Onshore and offshore production facilities
