A peripheral protection device for two metal pieces (10, 12) fitted into one another and having a general flange shape, the first (12) of which has an edge (18) extending outwards and the second (10) of which has a marginal zone, a first part (14) of which has substantially the form of a capital S whose vertical axis is substantially parallel to the edge (18) and a second part (16) of which is substantially perpendicular to the edge (18) consists of an arc having, in section, the general form of the capital letter C enclosing the edge (18) and the marginal zone.
An air-operated combination diaphragm spring brake has a tamper-resistant clamp provided between a head (46) and a spring side of a flange case (18) which together form a spring chamber (16) housing a power spring (72). The head (46) has an annular rim (70), and the flange case has an annular flange (74) with a diaphragm (48) sandwiched therebetween in an interface (76). An annular retaining member (78) has a lip (86) which tightly captures a step (80) on the annular rim as the annular retaining member (78) is drawn over the interface (76) to form the tamper-resistant clamp.
