Abstract: Hand pliers for assembly purposes includes an assembly limb and a handle limb rotatably connected to one another via a first link joint. The handle limb is divided into an off-handle lever and a handle-near lever and these two levers are rotatably connected to one another by a bolt via a second link joint, wherein a tension wheel and a ratchet wheel with external toothing connected torsionally proof to it are pivotably arranged on the bolt side by side in axial direction, and the tension wheel engages into a tension device that connects both handle limbs to one another, and a spring-loaded dog ratchet is arranged at the handle-near lever, engaging into the ratchet wheel in such a manner that when the handle-near lever makes a latching movement it permits a rotation of the ratchet wheel on closing the pliers, but prevents its rotation in the opposite direction.

Abstract: The invention relates to a hand pliers for assembly purposes, more particularly for the assembly of pipe connections at pipe systems, the pliers comprised of two limbs which are rotatably connected to one another via a first link joint (1) and which by means of this link joint (1) are divided into an assembly limb and a handle limb (2,3), wherein the first handle limb (3) is divided into an off-handle lever (14) and into a handle-near lever (15) and wherein these two levers (14, 15) are rotatably connected to one another by means of a bolt (16) via a second link joint, wherein a tension wheel (17) and a ratchet wheel (18) with external toothing (27) connected torsionally proof to it are pivotably arranged on the bolt side by side (16) in axial direction, and wherein the tension wheel (17) engages into a tension means (20) that connects both handle limbs (2,3) to one another, and wherein a spring-loaded dog ratchet (25) is arranged at the handle-near lever (15), the dog ratchet engaging into the ratchet wheel

Abstract: A pipe connection includes a metal locking ring which can be pushed onto the external pipe of two interlocking metal pipes to connect the latter. The inner face of the locking ring has a leading section that tapers conically in a radial direction in opposition to the direction of application; a trailing section that tapers conically in a radial direction in opposition to the direction of application and that causes the pipe to be radially compressed, when the ring is in the locking position; and a central section lying between the leading section and the trailing section. A central section with a conical configuration improves a pipe connection of this type so that the tensile strength of heavy duty pipe connections or pipe connections consisting of pipes of material with low elasticity becomes mechanically more stable.