Abstract: A process of producing a polyolefin, in one embodiment a polyethylene, and in a preferred embodiment a bimodal polyethylene comprising a high molecular weight component and a low molecular weight component, the process comprising providing a polyolefin having an I21 value of from 2 to 100 g/10 min and a density of from 0.91 to 0.97 g/cm3; followed by forming a melt of the polyolefin and passing the polyolefin through one or more active screen filter(s) having a mesh size of from 70 to 200 micron at a mass flux of from 5 to 100 lbs/hr/square inch; and isolating the polyolefin having passed through the screen filter.

Abstract: An improved mechanical-over-hydraulic steering apparatus capable of providing automotive-type steering includes a steering wheel driven input control member, right and left turn control valves, and first and second actuators mounted for rotation along an axis common with the input control member. Each of the actuators has a cam operatively associated with a cam-following roller assembly that operates the respective control valve. The vehicle has a cross drive mechanism, and the steering apparatus includes an over-center variable displacement steering pump and associated displacement control controllably operated by first and second pilot lines connected to the right and left turn control valves. The steering pump controllably and bidirectionally communicates fluid to a steering motor for the steering input to the cross drive mechanism.

Abstract: A brake system (10) providing a self-bleeding and self-cleaning operation as a function of selective positioning of the transmission control (16) of the vehicle. The brake (12,13), in the illustrated embodiment, is a spring-applied, hydraulically released brake permitting the piston (24) to force hydraulic fluid and accumulated air from an upper portion (34) of the brake pressure chamber (23) outwardly through a bleed line (33) in which a flow restrictor (35) and a check valve (36) are provided. A brake fluid inlet supply line (14) communicates with a lower portion (22) of the pressure chamber (23) so as to permit flushing of debris from the lower portion (22) of the pressure chamber (23) concurrently with the self-bleeding operation.