Grid - iron grate - an element of the headset of the furnace of a heating furnace or boiler for a steam heating system, as well as part of a roasting or sintering trolley . It is a cast-iron or steel monolithic or composite grate, which serves to maintain a layer of solid fuel or mixture .
The grate in the furnaces of the furnaces has openings or slots through which, in particular, ash wakes up under it. Cast iron grate by design are solid and type-setting. Steel grates are chain and pipe.
Content
- 1 In energy and heating boilers
- 2 In steam locomotives
- 3 In metallurgy and mining
- 4 notes
In energy and heating boilers
Grate bars are in most layered fireboxes . If the blast is lower, combustion air enters through it, if the upper one, combustion products and unburned gaseous component of fuel are removed through it. With the upper blast, the grill can be drawn from pipes cooled from the inside; this increases the service life of the metal and provides an additional highly efficient heat transfer surface. In pyrolysis boilers, instead of the grate, there may be a narrow nozzle for gases that retains heat in the loading chamber. In boilers there is no top burning of a grate; air passes only in the upper part of the fuel layer horizontally.
In some boilers of medium power (with a capacity of up to 10 kg / s steam ) the grate is made mobile. A chain grate is a cloth of shaped grate connected by chains that are driven by asterisks . The main disadvantage of such gratings is the increased heat loss from incomplete combustion of fuel [1]
In steam locomotives
The grate of locomotives has a rectangular shape and is assembled from individual elements. When designing its area is calculated based on the type of fuel on which the engine will work. Of the Soviet steam locomotives, the prototype AA20-01 steam locomotive had the largest grate; the area of its grate was 12 m². For American steam locomotives, the grate area could reach 17 m².
In metallurgy and mining
The grate is part of the firing carts for the production of sinter and pellets . As a rule, it is recruited from individual grid-irons made of heat-resistant steel .
Notes
- ↑ Dvoinishnikov V.A. et al. Design and Calculation of Boilers and Boiler Installations: Textbook for technical schools in the specialty "Boiler Building" / V. A. Dvoinishnikov, L. V. Deev, M. A. Izyumov. - M .: Mechanical Engineering, 1988 .-- S. 43, 44. - 264 p. - ISBN 5-217-00078-3 .