Pre-heat strategy: getting the die to operating temperature without killing it

Why a cold die under a hot billet writes off the first few parts and a piece of the die's service life with them, and how induction, gas-ring, and oven preheats each fit different shops.

7 min readLesson 2 of 13

Knowledge check

A shop pulls an H13 forge die out of the rack at 25°C, bolts it into the press, and starts running 1100°C billets without preheat. The operator says the first three parts are always scrap and the die warms up by the fourth. What is wrong with that practice in terms of die life, and what is the minimum acceptable preheat target and soak condition before the first hit?