Abstract: A protective cylinder (3) for pipe insulation. The protective cylinder (3) is cut at the rear side of the upper part of a folded section of one edge through a predetermined vertical distance 1.sub.1 from the upper end of a first longitudinal edge. The cut extends obliquely downwardly and outwardly at the front by the same vertical distance 1.sub.1 along a first guide line (9) obliquely downwardly and outwardly extending from a first radius portion (9a) at the upper end of the one edge, to an outside bent portion, to form thereby a first engagement portion extending along the first guide line. This serves as both a fitting guide and a rotation stopper. The cylindrical member also has a second longitudinal edge cut slightly obliquely outwardly and downwardly at the upper part thereof by a predetermined vertical distance 1.sub.3 from a second radius portion (10a) at the upper end of the other edge spaced at a horizontal distance 1.sub.2 from the second longitudinal edge.

Abstract: A plastics elbow cover (A) capable of being positively and securely mounted on an elbow section of piping. The elbow cover includes a tab (9, 10) extending from each of two sides of a cover section (8) which fits over the pipe. One of the tabs (9) includes: a tongue (9a) which engages a hole (10c) formed by a bridge (10d) on the other tab (10).

Abstract: A plastics cover for a piping which comprises a plastics cover body of a wide strip-like shape and a substantially T-shaped rib arranged on one side edge of the cover body. The rib includes a leg portion connected to the cover body and a wing portion, so that an inner groove and an outer groove is defined between the wing portion and the cover body. Mounting of the cover on a pipe is carried out by interengaging a first engagement projection on the inner surface of the wing portion and a second engagement projection on the outer surface of the other side edge of the cover body.