2.2 2.9 3.5 B8 B8m B8t Astm A453 Gr660 A286 Cross Recessed Pan Head Tapping Screws And Plain Washer

These miniature tapping screws (diameters 2.2mm, 2.9mm, 3.5mm) are designed for extreme high‑temperature service. The material conforms to ASTM A193 (B8, B8M, B8T) or ASTM A453 Grade 660 (A286 superalloy). These alloys retain significant strength up to 650‑700°C while resisting oxidation and creep. The screw has a cross recessed pan head and a plain flat washer (same material) pre‑assembled. The tapping thread cuts its own mating thread into metal sheet or cast holes, eliminating pre‑tapping. Typical applications include exhaust systems, furnace components and turbine accessories.

• Automotive exhaust manifolds and catalytic converter shells – temperatures up to 800°C (A286).
• Industrial kilns and burners – fixing refractory liners, thermocouple sleeves.
• Gas turbines and turbocharger housings – high‑temperature bolting.
• Petrochemical cracking furnace attachments – B8T resists intergranular corrosion.
• High‑temperature sensor housings – miniature sizes for tight spaces.

• Ultra‑high temperature capability – A286 retains >600 MPa at 650°C.
• Self‑tapping design – no need to pre‑tap holes in high‑alloy castings.
• Miniature precision – 2.2mm diameter fits compact high‑temp electronics.
• Heat‑resistant washer integrated – prevents preload loss.
• Multiple alloy options – B8M for chloride‑rich high‑temp environments, B8T for sensitisation resistance.