SAE J518-2-2023
Hydraulic Flanged Tube, Pipe, and Hose Connections, Four-Screw Flange Connection - Part 2: 42 Mpa (Code 62)

Standard No.

SAE J518-2-2023

Release Date

2023

Published By

Society of Automotive Engineers (SAE)  US  /  SAE

Latest

SAE J518-2-2023

Introduction

Core changes of the standard revision

Revisions	2017 Edition	2023 Edition
Referenced Standards	ASME B18.22.2	Dispersed to ASME B18.3/B18.21.1, etc.
Pressure Marking	Working Pressure	Maximum Working Pressure
Corrosion Resistance Requirements	General Description	New Regulations for 96-Hour Salt Spray Test

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Analysis of Key Technical Indicators

Material Performance Requirements

Components	Minimum Yield Strength	Elongation
Flange Head	215MPa	≥10%
Flange Clamp	330MPa	≥3%

Anti-Corrosion Protection System

Marking difference: SAE flange head needs to add circumferential groove marking (see Figure 3)

Thread specification: Inch thread ports are prohibited in new designs

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Implementation Recommendations

Key Installation Steps

1. Use phosphate coated screws (torque values are calibrated based on this condition)
2. Tighten in stages according to the cross-shaped sequence shown in Figure A1
3. Components DN ≥ 51 require FEA verification

O-Ring Selection

Material Type	Temperature Range(℃)	Pressure Reduction Factor
Carbon Steel	-40~+120	100%
Stainless Steel

Parameters	Requirements
Material	NBR Nitrile Rubber (default)
Hardness	90IRHD±5
Quality Standard	ISO 3601-3 Grade N

Technological Evolution Analysis

The 2023 edition mainly reflects three major technological trends:

• Global Adaptation: Full transition to the metric system, with imperial specifications only retaining compatibility support
• Environmental Upgrade: Elimination of harmful surface treatment processes such as those containing cadmium/hexavalent chromium
• Test Method Optimization: Introducing ISO 19879 as the test benchmark for hydraulic connectors

SAE J518-2-2023 Referenced Document

• ASME B18.21.1 Washers: Helical Spring-Lock@ Tooth Lock@ and Plain Washers (Inch Series)
• ASME B18.3 Hexagonal keyed and splined cylindrical head hexagonal shouldered set screws (Imperial series)
• ASTM A574 Standard Specification for Alloy Steel Socket-Head Cap Screws
• ASTM B117 Standard Practice for Operating Salt Spray (Fog) Apparatus
• ASTM F436 Standard Specification for Hardened Steel Washers
• ISO 10763 Hydraulic fluid power — Plain-end, seamless and welded precision steel tubes — Dimensions and nominal working pressures
• ISO 19879 Metallic tube connections for fluid power and general use - Test methods for hydraulic fluid power connections
• ISO 21920-1 Geometrical product specifications (GPS) — Surface texture: Profile — Part 1: Indication of surface texture
• ISO 261 ISO general purpose metric screw threads - General plan
• ISO 263 ISO inch screw threads; General plan and selection for screws, bolts and nuts; Diameter range 0,06 to 6 in
• ISO 273 Fasteners; Clearance holes for bolts and screws
• ISO 2768-1 General tolerances; part 1: tolerances for linear and angular dimensions without individual tolerance indications
• ISO 2768-2 General tolerances; part 2: geometrical tolerances for features without individual tolerance indications
• ISO 3601-1 Fluid power systems - O-rings - Part 1: Inside diameters, cross-sections, tolerances and designation codes; Technical Corrigendum 1
• ISO 3601-3 Fluid power systems — O-rings — Part 3: Quality acceptance criteria
• ISO 4017 Fasteners — Hexagon head screws — Product grades A and B
• ISO 4762 Hexagon socket head cap screws
• ISO 48-2 Rubber, vulcanized or thermoplastic - Determination of hardness - Part 2: Hardness between 10 IRHD and 100 IRHD
• ISO 6162-2 Hydraulic fluid power - Flange connections with split or one-piece flange clamps and metric or inch screws - Part 2: Flange connectors, ports and mounting surfaces for use at a pressure of 42 MPa (420 bar), DN 13 to DN 76
• ISO 6892-1 Metallic materials — Tensile testing — Part 1: Method of test at room temperature
• ISO 7089 Plain washers - Normal series - Product grade A
• ISO 724 ISO general purpose metric screw threads — Basic dimensions
• ISO 725 ISO inch screw threads - Basic dimensions
• ISO 898-1 Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws and studs with specified property classes - Coarse thread and fine pitch thread; Technical Corrigendum 1
• ISO 9227 Corrosion tests in artificial atmospheres — Salt spray tests — Amendment 1: Footnote of Warning*， 2024-02-19 Update
• SAE J2593 Information Report for the Installation of Fluid Conductors and Connectors
• SAE J429 Mechanical and Material Requirements for Externally Threaded Fasteners
• SAE J518-1 Hydraulic Flanged Tube, Pipe, and Hose Connections, 4-Screw Flange Connection Part 1: 3.5 MPa to 35 MPa (Code 61)
• SAE J846 Coding Systems for Identification of Fluid Conductors and Connectors

SAE J518-2-2023 history

• 2023 SAE J518-2-2023 Hydraulic Flanged Tube, Pipe, and Hose Connections, Four-Screw Flange Connection - Part 2: 42 Mpa (Code 62)
• 2017 SAE J518-2-2017 Hydraulic Flanged Tube, Pipe, and Hose Connections, 4-Screw Flange Connection Part 2: 42 MPa (Code 62)
• 2013 SAE J518-2-2013 Hydraulic Flanged Tube, Pipe, and Hose Connections, 4-Screw Flange Connection Part 2: 42 MPa (Code 62)

Standard and Specification