The new diaphragm arrived wrapped in a flour cloth.
Its maker unrolled it on Irna’s clean bench, showed the reinforced rim and made Iven put his thumb against the flexible center before she accepted the balance of her fee.
“Feel that fold.”
He did.
A small ridge ran beneath the surface where the woven reinforcement changed direction.
“Not a defect,” she said. “But don’t put the ridge across the clamp’s knife edge. This mark goes upper left.”
She had named the orientation on the drawing. She wanted the people fitting it to understand the material, not merely obey a little arrow.
The diaphragm was woven fiber sealed with a cured plant-resin film, suitable for the low-pressure signal coupling. It was not a substitute for every hot-water seal in the region. The maker wrote its temperature and pressure limits on the wrapping, then made Irna’s machinist copy them into the part record.
