摘要 |
1281672 Forming from a tube CATERPILLAR TRACTOR CO 12 Feb 1970 [19 Feb 1969] 6879/70 Heading B5A A tube is deformed, e.g. to form 0-ring grooves therein, by placing it in a grooved die, placing a resilient member in the tube and compressing the resilient member by a force coincident with the tube axis to expand it radially into the die cavity, thereby deforming the tube. As shown in Fig. 1, the tube 10 is placed in a die formed by split moulds 12, 14 against a stop 18 of mould collar 20. A resilient member 21, e.g. of polyurethane is placed in the tube and compressed by hydraulic pressure applied to plunger 22 having head 24. Member 21 is expanded laterally thereby,- forming the tube against die cavity 26. |