Heavy stokers

Elevated grate stokers are designed to combust fine coal in the water and steam boilers of the output of 6 – 50 MW.

Purpose

The grates of type: RTWC, RTWK, RŁ are designed for combustion fine coal in the boilers of efficiency from 3 to 60 MW. Boilers of the efficiency from 3 to 20 MW have single grate stoker, however, in the boilers of power from 25 to 60 MW, apply double grate stoker. The air-boxes  of the stokers are divided for the hermetic areas. The area is specified as space around the air hopper. Construction of the air-box allows for individual supplying of air to each area and provides whole air-tightness between it. Thanks that, we provide significant control of quantity air provided to separate areas of grates. Quantity of areas depends on the type of boiler and length of the stoker. Optimal quantity of areas should consider proportion between “dead” fields among areas and the total surface of grate . Grate bars, chains are prepared in the standard system or in high-strength system for heat load (e.g. chain made of chromium-manganese steel, grate bars of up to 2,5% chrome content). Dosage of the fuel shall be provided using a standard basket (arched sliding bolt) or a cascade basket (dispensing drum). For the standard baskets a reversible truck can be used (in order to distribute evenly coal granulate on the grate surface). The shafts of the grates are mounted on the barrel bearing with enlarged clearance, which are lubricated locally or using systems of automatic lubricating. For the drive of heavy grate the worm gears of the type: BNr-2000 or BNr-1000 with the gear-motor designed for operating with the inverter are used.

Thanks to applying by our design office the latest solutions concerning the heavy grate stokers, increasing of combustion process efficiency is possible, as well as increasing efficiency of the whole boiler, and reducing coefficient of the air excess and the oxygen content in the fumes.

Technical data

Maximum heat load of the grates: 1280 kW/m².

Heating value of fuel consumed:  19 – 28 MJ/kg.

Received efficiency of combustion on the grate amounts to 97,5% in the ranges from 50 to 100 % of nominal efficiency of the boiler.

We provide full service under the guarantee and post-guarantee as well as all replacement parts.

Heavy grates

1) Lateral left/right support , 2) Lateral left/right support 3) JW Support., 4) OW Support, 5) Chain – element t=203, 6) Roller 355, 7) Grate bar (395,345), 8) Distance rod 9) Tensioning screw