tubing 28 around the bend of pipe happens in the plane 106 b as indicated by section line u201c 8 8 u201d passes through the centerline 106 c of pipeline bend 16 however it is supported at contacts 102 and 104 as forces 106 d and 106 e which are each shown graphically as 1 12 of the force 106 a forces 106 f and 106 g are the normal to the surface forces associated with forces 106 d and 106 e respectively and they are larger by the inverse of the cosine of the angle 106 h meaning that the friction force causing normal contact force has increased assisting the bend protector in remaining in position as the coiled tubing is pulled back through the pipeline bend 16 this angular contact can be pushed to about 45 degrees to each side which would amply the force about 41 over plain steel on steel contact referring now to fig1 shear pin 88 is illustrated as an all thread brass piece with a hex 108 broached all the way through to make it easy to install remove and to shear this style construction means that both ends of the shear pin will be positively restrained rather than being lost in the pipeline to cause other problems referring now to fig1 individual section 110 is shown with rollers 112 a d being mounted on axles 114 a d rather than having an insert 80 of low friction.