Hydraulic intensifier

An improved hydraulic intensifier for oil well fracturing, erosion drilling or the like having a bed and at least two intensifier units mounted on said bed in which the intensifier units each include a hydraulic piston motor connected in direct driving relation to a working ram, the improvement in intensifier structure providing for ease of maintenance in the field comprising means defining a back wall, an intermediate wall spaced from said back wall and a front wall spaced from said intermediate wall, the cylinder of said hydraulic piston motor positioned between said back wall and said intermediate wall, the working ram including a ram cylinder supported in an opening formed on said front wall, said front wall, intermediate wall and back wall being joined by a plurality of tension rods, spacer sleeves on said rods between said intermediate wall and front wall and defining therebetween a generally open clearance space, a piston rod assembly in said cylinder having a forward end extending into said space, a working ram received in said ram cylinder and having a rear end received in said space, removable coupling means in said space joining said rod and ram, the axial length and transverse width of said clearance space being greater than the corresponding length and width of either said ram or ram cylinder, said ram and said ram cylinder being removable through said space without distrubing said tension rods.