SCHWERLL Standard Seamless Formed Fixed Pressure Vessel Cylinders are stationary cylindrical pressure vessels engineered for accumulator-system backup service. Built with seamless-formed construction, this standardized vessel series is designed for cyclic and alternating-stress duty in fluid-power energy storage systems.
SCHWERLL offers customers standard pressure-vessel cylinders and integrated cylinder banks with common nominal volumes including 20 L, 35 L, 40 L, 50 L, 75 L, and 100 L, with modular configurations scaling up to 500 L. Typical published common design pressures include 20 MPa, 31.5 MPa, and 35 MPa, with final pressure ratings and connection interfaces confirmed for the supplied configuration.
1. Product Architecture & Stationary Scope Boundary
Standard seamless-formed pressure vessels represent the core gas-side energy storage component within hydraulic accumulator installations. These vessels function as auxiliary gas backup reservoirs that expand effective gas volume without requiring additional moving parts.
π Stationary Installation & Scope Notice
Stationary Installation & Scope Notice: This product is presented by SCHWERLL as a fixed/stationary pressure-vessel cylinder for hydraulic accumulator-system backup service. Transportable compressed-gas-cylinder applications fall under a separate product and regulatory scope and require independent technical review.
Key architectural characteristics of the seamless-formed series include:
- Seamless Formed Shell: Fabricated with seamless construction, eliminating longitudinal weld seams and associated stress concentrations.
- Cyclic Duty Context: Engineered for cyclic and alternating-stress duty in accumulator-system backup service.
- Standardized Specification: Series-manufactured geometry provides dimensional consistency and well-defined technical specifications.
- Modular Bank Integration: Sized for individual installation or integration into multi-vessel gas storage banks.
2. Published Parameters & Technical Sizing Matrix
The standard seamless-formed cylinder family covers the most frequent industrial hydraulic capacity requirements. Sizing can be selected as individual standalone bottles or interconnected in multi-vessel manifold banks.
| Nominal Volume (L) | Published Common Pressures | Construction Method | Duty Regime | Typical Application Role |
|---|---|---|---|---|
| 20 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Compact accumulator gas-side backup |
| 35 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Standard bladder accumulator gas-side expansion |
| 40 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Auxiliary accumulator gas backup |
| 50 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Standard industrial accumulator backup units |
| 75 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Standby accumulator gas-side backup |
| 100 L | 20 / 31.5 / 35 MPa | Seamless Formed | Cyclic Pressure Service | Stationary accumulator gas backup banks |
| Up to 500 L | Project-Confirmed | Seamless Formed | Cyclic Pressure Service | Large-capacity stationary auxiliary gas storage configurations |
*Note: Final vessel dimensions, port connections, test pressures, materials, and documentation scope are confirmed during order engineering review.
3. Hydraulic System Standby & Auxiliary Gas-Side Integration
In hydraulic installations, standard seamless-formed vessels are connected to the gas port of bladder or piston accumulators via high-pressure gas piping or manifold assemblies. This architecture yields substantial engineering benefits:
- Gas Volume Multiplication: By coupling one or multiple gas backup cylinders to an accumulator, the available gas volume is multiplied while maintaining a compact hydraulic interface footprint.
- Pressure Stability: An enlarged gas volume flattens the operating pressure gradient, supporting consistent hydraulic pressure across the work cycle.
- System Protection via Dedicated Safety Blocks: For code-compliant safety shut-off, overpressure relief, and controlled venting, SCHWERLL integrates the SCHWERLL Accumulator Safety & Shut-Off Valve Block directly at the hydraulic and gas boundaries.
- Multi-Bottle Rack Arrangements: Where large volumes of auxiliary gas must be organized efficiently, multiple standard seamless cylinders can be packaged within a SCHWERLL High-Pressure Accumulator Gas Bottle Rack / Nitrogen Storage Bank with integrated isolation and instrumentation manifolds.
4. Structural Design, Materials & Cyclic Fatigue Durability
Because stationary accumulator gas cylinders experience continuous cyclic pressure fluctuations, structural fatigue resistance is the primary mechanical engineering requirement:
- Seamless Formed Construction: Formed vessel ends provide continuous metal structure without longitudinal welds, supporting reliable performance under cyclic operating pressure.
- Material Selection: Material selection is confirmed according to design pressure, cyclic duty, applicable project requirements and approved specification.
- Gas Medium & Compatibility: Gas medium and compatibility are confirmed for the supplied configuration.
- Corrosion Protection: External protective coating applied to suit industrial installation environments.
5. Manufacturing Quality Governance & Project Documentation
SCHWERLL executes pressure-vessel engineering and production under a certified corporate quality management framework:
- Corporate ISO 9001:2015 QMS: Governs raw material receiving inspection, manufacturing routing, dimensional validation, hydrostatic proof testing, and final quality dossier preparation.
- Pressure-Vessel Design Codes: Applicable pressure-vessel design-code, conformity-assessment and documentation requirements are reviewed according to project specification and destination (e.g. ASME Section VIII or EU PED requirements where specified).
- Quality Verification Regime: Quality verification can include hydrostatic proof testing, ultrasonic flaw detection, volumetric expansion verification, and gas tightness testing per agreed Inspection and Test Plan (ITP) and applicable pressure vessel code.
- Third-Party Inspection (TPI): Independent witness testing and certification by notified bodies or classification societies (such as TΓV, DNV, Lloyd’s Register, BV, or SGS) can be coordinated where mandated by customer contract.
6. Sizing Guidance & RFQ Technical Checklist
To obtain an accurate technical proposal and quotation for standard seamless-formed fixed pressure-vessel cylinders, please submit the following application parameters to our engineering desk:
- System Design & Maximum Allowable Working Pressure (MAWP): Specify required pressure rating (20 MPa, 31.5 MPa, 35 MPa, or custom).
- Required Gas Volume: Specify total required gas-side capacity (nominal L) and preferred single-vessel volume (e.g., 20 L, 40 L, 50 L, 100 L).
- Gas Medium & Compatibility: Gas medium and compatibility are confirmed for the supplied configuration.
- Cyclic Duty Context: Describe operating cycle frequency, expected pressure differentials (ΞP), and target service life requirements.
- Connection & Mounting Interface: Indicate preferred port connections, mounting arrangements, or manifold interface requirements.
- Project Design Code & Documentation Scope: State destination jurisdiction, applicable pressure vessel regulations, and any required third-party inspection (TPI) witness requirements.
Our application engineering team provides technical review, thermal dissipation checks, and real-gas compressibility calculations to confirm optimal vessel sizing for your fluid power circuit.
