JIS B 1189 Flange Bolt
JIS B 1189 flange bolts are hexagon head bolts with an integrated flange beneath the head, providing a larger bearing surface for distributing clamping pressure over the assembled components. The flange also helps reduce the need for a separate washer in many fastening applications, while the hexagonal head allows convenient installation and removal with standard tools. These bolts are widely used in machinery, automotive components, industrial equipment and other applications requiring compact and reliable bolted connections.
We manufacture flange bolts according to JIS B 1189 requirements, with different metric sizes, thread configurations, lengths, materials and strength grades available for specific applications. Carbon and alloy steel options can be supplied in commonly specified strength classes such as 4.8, 6.8, 8.8, 9.8 and 10.9 under the applicable JIS requirements, while stainless steel options are available for applications where corrosion resistance is important. Surface finishes and special requirements can also be provided according to the selected specification and customer requirements.
Specification:
JIS B 1189 specifies hexagon bolts with flange and defines requirements for their dimensions, product specifications and marking. The standard covers metric flange bolts with coarse and fine pitch threads, including configurations corresponding to ISO 15071 and ISO 15072. Depending on the applicable product configuration, flange bolts are available in carbon or alloy steel strength classes as well as stainless steel A2-70.
| Item | Specification |
|---|---|
| Standard | JIS B 1189:2014 |
| Product Type | Hexagon Bolts with Flange |
| Thread Standard | ISO 68-1,ISO 965 |
| Thread Type | Coarse/Fine Pitch |
| Thread Tolerance | 6g |
| Shank Configuration | Full Shank/Reduced Shank |
| Size Range | M5-M16 |
| Material | Carbon Steel, Alloy Steel, Stainless Steel |
| Steel Class | 4.8,8.8,10.9 |
| Stainless Steel Class | A2-70/80,A4-70,80 |
| Mechanical Property Standard | JIS B 105, JIS B 1054-1 |
| Surface Treatment | Zinc plated, Black Oxidation, Dacromet, Bright Finish,Passivation |
| Related ISO Standard | ISO15071/ISO15072 |
| Inspection | Dimensions, Thread,Mechanical Property,Coating |
Dimension Chart of JIS B1189 Flange Bolts:
The dimension chart below shows the standard dimensions of JIS B 1189 flange bolts in the F type configuration. It includes the key dimensions such as nominal diameter, head width, head height, flange diameter, flange thickness, bolt length and thread length. Dimensions vary according to the selected bolt size and thread configuration.
The F type features a bearing surface without an undercut beneath the flange and is available in metric coarse and fine pitch thread configurations according to the applicable JIS B 1189 requirements. Please refer to the chart below for the detailed dimensions of each available size
| Mon | M5 | M6 | M8 | M10 | M12 | M14 | M16 |
| P | 0.8 | 1 | 1.25 | 1.5 | 1.75 | 2 | 2 |
| da max | 6.2 | 7.5 | 10 | 12.5 | 15.2 | 17.7 | 20.5 |
| dc max | 11.4 | 13.6 | 17 | 20.8 | 24.7 | 28.6 | 32.8 |
| ds max | 5 | 6 | 8 | 10 | 12 | 14 | 16 |
| ds min | 4.82 | 5.82 | 7.78 | 9.78 | 11.73 | 13.73 | 15.73 |
| e min | 7.59 | 8.71 | 10.95 | 14.26 | 16.5 | 19.86 | 23.15 |
| k max | 5.6 | 6.9 | 8.5 | 9.7 | 12.1 | 12.9 | 15.2 |
| Lf max | 1.4 | 1.6 | 2.1 | 2.1 | 2.1 | 2.1 | 3.2 |
| r max | 0.25 | 0.26 | 0.36 | 0.45 | 0.54 | 0.63 | 0.72 |
| r min | 0.1 | 0.11 | 0.16 | 0.2 | 0.24 | 0.28 | 0.32 |
| s max | 7 | 8 | 10 | 13 | 15 | 18 | 21 |
| s min | 6.78 | 7.78 | 9.78 | 12.73 | 14.73 | 17.73 | 20.67 |
Mechanical Property of JIS B 1189 Flange Bolt:
Carbon & Alloy Steel JIS B 1189 Flange Bolts — JIS B 1051/ISO898-1
JIS B 1189 flange bolts made from carbon and alloy steel can be supplied to the strength classes specified in JIS B 1051, which is technically identical to ISO 898-1:2013.
| Mechanical or physical property | Property class | ||||||||
| 4.6 | 4.8 | 5.6 | 6.8 | 8.8 (d≤16mm) | 8.8(d＞16mm) | 10.9 | 12.9 | ||
| Tensile strength, Rm, MPa | nom. | 400 | 400 | 500 | 600 | 800 | 800 | 1000 | 1200 |
| min. | 400 | 420 | 500 | 600 | 800 | 830 | 1040 | 1220 | |
| Lower yield strength, ReL d, MPa | nom. | 240 | - | 300 | - | - | - | - | - |
| min. | 240 | - | 300 | - | - | - | - | - | |
| Stress at 0,2 % nonproportional elongation, R p0,2, MPa | nom. | - | - | - | - | 640 | 640 | 900 | 1080 |
| min. | - | - | - | - | 640 | 660 | 940 | 1100 | |
| Percentage elongation after fracture for machined test pieces, A, % | min. | 22 | - | 20 | - | 12 | 12 | 10 | 8 |
| Percentage reduction of area after fracture for machined test pieces, Z, % | min. | - | 52 | 48 | 44 | ||||
| Vickers hardness, HV F W 98 N | min. | 120 | 130 | 155 | 190 | 250 | 255 | 320 | 385 |
| max. | 220 | 320 | 335 | 380 | 435 | ||||
| Rockwell hardness, HRC | min. | - | - | - | - | 22 | 23 | 32 | 39 |
| max. | - | - | - | - | 32 | 34 | 39 | 44 | |
Stainless Steel JIS B 1189 Flange Bolts — JIS B 1054-1 / ISO 3506-1
For stainless steel JIS B 1189 flange bolts, we offer A2-70, A2-80, A4-70 and A4-80 grades. A2 grades are typically selected with 304/304L stainless steel, while A4 grades use 316/316L.
| Stainless Steel Grade | Property Class | Tension Strength(min)MPA | Stress at 0.2% non-proprotional elongation(min)MPA | Elongation after fracture(min)mm |
| Austenitic | A2-50 | 500 | 210 | 0.6d |
| A2-70 | 700 | 450 | 0.4d | |
| A2-80 | 800 | 600 | 0.3d | |
| A4-50 | 500 | 210 | 0.6d | |
| A4-70 | 700 | 450 | 0.4d | |
| A4-80 | 800 | 600 | 0.3d | |
| Duplex | D6-70 | 700 | 450 | 0.4d |
| D6-80 | 800 | 600 | 0.3d |
Application of JIS B 1189 Flange Bolt:
Automotive & Transportation Equipment
JIS B 1189 flange bolts are widely suited to automotive components, motorcycles, agricultural machinery and transportation equipment where compact and reliable fastening is required. The integrated flange provides a larger bearing surface under the bolt head, helping distribute clamping force across the assembled component.
Machinery & Industrial Equipment
These flange bolts are commonly used in machinery, pumps, motors, production equipment and general mechanical assemblies. Their integrated flange can simplify assembly by providing a built-in bearing surface, making them useful where installation space is limited or reducing the number of separate fastening components is desirable.
Outdoor & Corrosion-Resistant Applications
Stainless steel JIS B 1189 flange bolts are suitable for equipment and assemblies exposed to moisture, weather and other corrosive conditions. The A2-70 stainless steel option provides corrosion resistance together with suitable mechanical performance for general industrial, outdoor and mechanical applications.