KPF Obtains Japan’s F8T HDG Certification

KPF has recently obtained the official Dai-Shin (代審) certification for the F8T HDG specification from Japan’s Ministry of Land, Infrastructure, Transport and Tourism (MLIT), becoming the only foreign company capable of supplying the full range of structural bolt specifications to the Japanese construction market.

With this certification, Japanese clients—who previously had to place separate orders due to fragmented certification coverage—can now procure S10T, F10T, and F8T HDG products in a single consolidated order, significantly improving both convenience and operational efficiency.

The F8T HDG specification is used for galvanized high-strength bolts in structural applications, distinguishing it from S10T and F10T products, which are typically supplied without surface treatment.

The F8T HDG segment is estimated to account for approximately 5% of the total high-strength bolt demand in Japan, representing a market volume of around 500 tons per month. While direct sales from this product line are expected, the greater impact lies in enhancing overall sales performance across the company’s entire bolt portfolio through improved client integration and ordering flexibility.

Currently, only three to four manufacturers in Japan are known to supply all three specifications (S10T, F10T, F8T HDG) across all sizes. Among foreign manufacturers, KPF stands alone in its ability to offer this full range—demonstrating not only its technical capabilities but also its exceptional responsiveness to Japan’s rigorous certification process.

KPF had previously secured JIS certification and S10T Dai-Shin certification in 2019 and 2021, respectively. With the addition of the F8T HDG certification, the company has now completed the full lineup of certifications required for high-strength structural bolts in Japan. This milestone is expected to open new opportunities for KPF in large-scale building projects and public infrastructure initiatives throughout the country.

* F8T Grade

A type of high-strength bolt (equivalent to 8.8 tensile class or higher), designed in accordance with Japanese building codes and typically used in structural steel applications.

* HDG (Hot-Dip Galvanizing)

A corrosion-resistant coating process where bolts are dipped in molten zinc. This treatment is essential for structures exposed to outdoor or high-humidity environments.