A material handling machine comprising: a boom, an arm, a grapple suspended on a front end of an arm of the machine; characterised by a piping guard comprising two guard plates (11a, 11a) each having a predetermined shape and a predetermined size and attached to opposite sides of the arm by bolts and nut bodies into which the bolts are screwed, a hydraulic hose or an electric power supply cord running along the arm, wherein: columnar or tubular members are used as stoppers which are provided at inner surfaces of the guard plates to prevent a shearing force from acting on the bolts due to displacements of the guard plates relative to the arm; the stoppers constituted by the columnar or tubular members are fixed by welding to places of back surfaces of the guard plates to abut against the nut bodies in a condition that a clearance is secured between each of bolt through holes provided in the guard plates and each of the bolts when the guard plates are attached to the opposite sides of the arm by the bolts and the nut bodies, and the stoppers abut against side surfaces of the nut bodies so that a collision force caused by collision of foreign matters with the guard plates is received by front end portions of the nut bodies or the guard plates through the stoppers. a boom, an arm, a grapple suspended on a front end of an arm of the machine; characterised by a piping guard comprising two guard plates (11a, 11a) each having a predetermined shape and a predetermined size and attached to opposite sides of the arm by bolts and nut bodies into which the bolts are screwed, a hydraulic hose or an electric power supply cord running along the arm, wherein: columnar or tubular members are used as stoppers which are provided at inner surfaces of the guard plates to prevent a shearing force from acting on the bolts due to displacements of the guard plates relative to the arm; the stoppers constituted by the columnar or tubular members are fixed by welding to places of back surfaces of the guard plates to abut against the nut bodies in a condition that a clearance is secured between each of bolt through holes provided in the guard plates and each of the bolts when the guard plates are attached to the opposite sides of the arm by the bolts and the nut bodies, and the stoppers abut against side surfaces of the nut bodies so that a collision force caused by collision of foreign matters with the guard plates is received by front end portions of the nut bodies or the guard plates through the stoppers. columnar or tubular members are used as stoppers which are provided at inner surfaces of the guard plates to prevent a shearing force from acting on the bolts due to displacements of the guard plates relative to the arm; the stoppers constituted by the columnar or tubular members are fixed by welding to places of back surfaces of the guard plates to abut against the nut bodies in a condition that a clearance is secured between each of bolt through holes provided in the guard plates and each of the bolts when the guard plates are attached to the opposite sides of the arm by the bolts and the nut bodies, and the stoppers abut against side surfaces of the nut bodies so that a collision force caused by collision of foreign matters with the guard plates is received by front end portions of the nut bodies or the guard plates through the stoppers.