Grade 8.8 Steel Internally Threaded Dowel Pin

Grade 8.8 Steel (class 8.8) is the workhorse medium-carbon alloy grade for structural joints. When internally threaded dowel pin are specified in this grade, the dimensions remain per GB/T 120.1 / ISO 8735; the material determines corrosion behavior (requires plating (zinc) for corrosion protection) and the service temperature range (up to approx. +300 °C). Both are covered below with the size table.

Why Choose Grade 8.8 Steel for Internally Threaded Dowel Pin — GB/T 120.1 / ISO 8735 (Series 099)

The workhorse medium-carbon alloy grade for structural joints. For internally threaded dowel pin — gb/t 120.1 / iso 8735 (series 099), this matters when requires plating (zinc) for corrosion protection is the primary requirement.

Mechanical & Physical Properties

Galvanic & Galling Considerations

For internally threaded dowel pin — gb/t 120.1 / iso 8735 (series 099) in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.

Comparable Grades

For Internally Threaded Dowel Pin — GB/T 120.1 / ISO 8735 (Series 099), class 10.9 or 12.9 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.

Sizes of Internally Threaded Dowel Pin — GB/T 120.1 / ISO 8735 (Series 099) Available in Grade 8.8 Steel