# US 4,781,048 A · Method of forming spirally wound gaskets

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- Number: US 4,781,048 A
- Document ID: US4781048A
- Status: Granted
- Kind: A
- Application number: 06/860,171
- Filed: 1986-05-06
- Granted: 1988-11-01
- Earliest claimed: 1985-05-10
- Assignees: Flexitallic Limited
- Inventors: Leslie Richardson
- Web page: https://patentgrep.com/patent/US4781048A

## CPC

- B65H 81/06: Covering or wrapping elongated cores
- F16J 15/125: {generally perpendicular to the surfaces}
- B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
- F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS

## Abstract

A spiral wound gasket is made by progressively winding strip material between co-operating rollers to form a gasket section, the method of manufacture including the step of separating the rollers at a predetermined rate to give a predetermined rate of growth for the gasket section formed between them.

## Claims

### Claim 1

A method of producing a spiral wound gasket formed by a plurality of superposed turns of strip material, said method comprising:
(a) progressively winding a metal strip between a pair of cooperating rollers;
(b) after winding at least one complete turn of said metal strip, introducing a strip of gasket filler material into the winding ahead of said pair of rollers to form superposed layers of said metal strip and said gasket filler material, wherein a discontinuity is formed in said winding when said gasket material is introduced; and, while continuing to wind said superposed layers of said metal strip and gasket filler material,
(c) positively separating said rollers at a predetermined rate to give a predetermined substantially constant rate of growth in diameter for a composite gasket section formed between said rollers, said rate being substantially without regard to any local variation in thickness of said layers.

### Claim 2 (depends on 1)

A method according to claim 1 including the step of selecting said predetermined rate of positive separation as a function of at least the thickness of the gasket filler strip material.

### Claim 3 (depends on 1)

A method according to claim 1 wherein said rate is selected to control the degree of compaction of the filler strip material, to produce composite gasket section of desired hardness.