Astec Industries, Inc.

J Don Brock

William R Gray

Herbert E Jakob

Erbie G Mize

Robert G Stafford

Malcom L Swanson

James G May

A method of manufacturing a large stationary, aggregate processing screening tower by fabricating weldment modules and preassembling them with aggregate processing equipment internal within the weldment modules, transporting the preassembled weldment modules to a field work site where the tower is to be erected on a foundation, aligning the modules and stacking the modules in layers and then bolting adjacent modules together. A large stationary, aggregate processing screening tower has weldment modules preassembled with aggregate processing equipment internal within the modules. The preassembled modules are stacked up on one another and secured together and can receive aggregate product at the top module and the product is processed by screening and sizing as it moves downwardly by gravity through the modules and their processing equipment for final clarification and collection of the product.

Large, stationary, modular aggregate processing plant and method of manufacturing and installing same

A rock crusher such as a cone or jaw crusher incorporates hardened tapered inserts in the manganese or other wear liner of at least one of its crushing elements. The inserts extend outwardly from the crushing surface of the crushing element towards the facing crushing surface so as, in use, to act as pick axes that shatter rock primarily by impact rather than pulverizing the rock by compression. The inserts are fixed in a heat treated manganese wear liner either by bonding or by press-fitting. The inserts substantially improve the life of the wear liner and, unexpectedly, 1) produce product of a highly uniform gradation in the desired ranges, 2) consistently produce product with a very high cubicity, 3) dramatically reduce the crusher's power requirements, and 4) significantly increase the crusher's capacity.

Rock crusher having crushing-enhancing inserts, method for its

A paving machine employs a screed heating system using heat from the exhaust system to heat indirectly the screed to the desired temperature. A heat exchange medium is heated by the exhaust system in a first heat exchanger and is then conveyed to a second heat exchanger where it heats the screed. Measures are taken to supply additional heat to the heat exchange medium as may be required to achieve the required heat transfer in the second heat exchanger. The system operates under low pressure and is thus simpler, less expensive, and less likely to fail than high-pressure systems. Preferably, the heat exchange medium is continuously circulated between the first and second heat exchangers in a closed-loop to minimize the amount of heat exchange medium required and to simplify the system. The system is also preferably designed to permit movement of the screed relative to the remainder of the paving machine and to permit flexing of the screed.

Paving machine employing exhaust heat exchanger for screed heating

A combustion chamber having improved heating efficiency and reduced NO.sub.x emissions includes a reduced diameter throat and a stepped configuration within the chamber. The chamber configuration encourages efficient combustion to reduce NO.sub.x production by promoting the formation of eddy currents within the chamber. A method for increasing heating efficiency and reducing NO.sub.x production is provided and involves passing combustion gases through such a combustion chamber.

Combustion chamber having reduced NO.sub.X emissions

Combustion chamber having reduced NO.sub.x emissions

A method for treating asphalt roofing shingles to be used for recycling in an asphalt plant which mixes asphalt roofing shingles with between about 15% and 50% by weight of a carrier aggregate. The aggregate is fed into a shredder with the shingles or is otherwise mixed with the comminuted shingles to form a recyclable asphaltic material which may be easily stored and transported, and which may also be used in the preparation of asphalt paving composition.

Method for preparing and storing a recyclable shingle material

An asphalt plant apparatus includes an inclined rotary drum dryer, the lower end of which is received within a concentric fixed sleeve. Aggregate is introduced into the upper end of the rotary drum dryer for heating and drying and is discharged from the lower end of the drum into an annular space between the drum and the concentric fixed sleeve. Recycleable asphalt pavement (RAP) and fines may be introduced into the annular space along with the heated and dried aggregate. Flights on the exterior of the rotating drum mix the aggregate and RAP and move the mixture toward the opposite end of the concentric fixed sleeve, heat from the heated aggregate, from the flights, and from the hot shell of the drum melting the asphaltic content of the RAP. Liquid asphalt is introduced into the sleeve for mixing along with the aggregate and RAP, and the resulting mixture is discharged from the sleeve for use as an asphalt paving composition.

Growing community of inventors

Chattanooga, TN, United States of America

J Don Brock