He calculated the tension required to seal the pump housing against the internal pressure. It was a high-stakes algebra problem. If he applied the torque for a standard hex bolt, he’d under-tighten it. If he guessed, he’d snap the bolt.
: Typically features a Phillips pan head screw paired with a helical split lock washer and a flat washer. jis b 1188 pdf
Unlike JIS B 1180, B 1188 does not require high tensile grades. The PDF will reference for mechanical properties of screws up to property class 4.8 (soft steel, low carbon). He calculated the tension required to seal the