Overview
ISO/TR 10946:2019 - "Hydraulic fluid power - Gas-loaded accumulators with separator - Selection of preferred hydraulic ports" provides guidance for selecting hydraulic ports on gas‑loaded accumulators with a separator (diaphragm, bladder or piston types). The technical report defines preferred port types, thread and flange options, connection interfaces (reducing bushes) and identification wording for products and documentation. It supports consistent port selection across hydraulic fluid power systems to ease interchangeability, production and maintenance.
Key topics
- Scope and terms: Defines accumulator types (bladder, diaphragm, piston) and interface terms consistent with ISO 5598.
- Preferred port standards: Recommends preferred threaded and flange ports and lists optional legacy or existing-application alternatives. Standards referenced include ISO 1179-1:2013, ISO 6149-1, ISO 7-1, ISO 11926-1, and flange standards ISO 6162-1 / 6162-2 / 6164.
- Thread and flange dimensions: Provides tables of recommended thread sizes and flange DN series by accumulator type (examples include G 1/4 to G 2, metric M14…M75, Rc and UNF sizes where applicable).
- Connection details: Illustrates thread connection possibilities and the role of a reducing bush as the interface between accumulator and hydraulic circuit.
- Application limits and pressures: Annex A defines useful pressure terms used in design and selection (pre‑charge p0, minimum/maximum working pressures p1/p2, set pressure, allowable/test pressures and allowable pressure ratios).
- Identification statement: Prescribes compliant wording for test reports, catalogues and sales literature when ports are selected per ISO/TR 10946:2019.
Applications and users
Who benefits from ISO/TR 10946:2019:
- Hydraulic system designers and OEMs selecting accumulator port types for new products.
- Accumulator manufacturers standardizing production ports and documentation.
- Procurement specialists specifying compatible ports for replacement parts or system integration.
- Maintenance and service teams ensuring correct port interfaces during repair or retrofits.
- Test labs and certification bodies using the identification statement in reports.
Practical uses:
- Choosing the right threaded or flange port for compatibility with hydraulic lines and fittings.
- Determining minimum shell/internal diameters associated with port sizes for piston accumulators.
- Aligning product documentation and catalogs with internationally recognized port standards.
Related standards
Keywords: ISO/TR 10946:2019, hydraulic ports, gas-loaded accumulators, separator, port selection, thread sizes, flange ports, hydraulic fluid power.