How to Convey Hot Stuff

Apron Conveyor

How to Convey Hot Stuff

Steel Apron Conveyor for Transport of hot Bulk Solid Materials
Steel apron conveyors are heavy duty conveyors especially for high temperature bulk materials. In the following some design specifications for a long lasting, failure free operation of such systems are presented by means of a newly developed solution.
(ed. WoMaMarcel - 09/10/2015)
<Blank Space>

The stability of the apron conveyor depends not only on the forces exerted by the weight of the transported bulk good, but also by the way the flux of force is transferred to the chain.

The conveyor cells of the SZB 250 are self-supporting and so they don’t need to be underpinned by pins and dogs (see Fig. 4), thus improving the durability of the chain.
The conventional fastening of the chain under the cells floor section using angular butt straps induces an additional moment due to the distance between chain and roller and the weight of the chain element. This moment spawns an additional load spectrum, which must be absorbed by the cells’ floor section. Directly fastening the chain to the roller retainer eliminates the load-arm and the additional load spectrum and increases the cells stability.

Fig. 4: Conveyor cells are self supporting

The transported material in the apron- conveyor exerts varying pressures against the floor section according to the differing load factor. The load of the rollers will exert a counteracting force which avoids the bending of the cell floor section, (Fig. 5). Also, the load upon the welded joint  between side and floor panel will be greatly reduced.

Fig. 5: Forces on the side walls

Further constructional features are:

  • The roller retainer constitutes a strong frame between side and floor panel.
  • The overhang of the side panel is evenly split between sides of the floor section.
  • Due to its short length the roller axis is very bending resistant and therefore contributes to the systems stability.

The bolted connection between the floor section, roller and chain won’t come into contact with the bulk material and so  won’t be exposed to special thermal stress.
As an apron conveyor can not be built like a continuing belt conveyor, but rather of many overlapping single cells, the leak tightness and wear resistance are of parti­cular importance. Here the new apron conveyor is supposed to set new standards.

As regards the topic leak tightness it can be summerised as follows (Fig. 6):

  • The geometry of the hinge is optimally adapt to all chain sizes (the pivot point is the same for all chain sizes).
  • The sealing properties are optimally adapted to all sprocket dimensions. (Even on a sprocket no material remains in the sealing chamber).
  • Self cleaning of the sealing chamber.
  • No risk of destruction through material deposits on the return strand.

Fig. 6: Leak tightness of the conveyor cells at various pivoting angles (P.A.) when passing over various-size sprockets: a) Z = 7,5, P.A. = 24°; b) Z = 7,5, (maximum) P.A. = 48°; c) Z = 10.5, P.A. = 34°; d) Z = 12.5, P.A. = 29°.

Most read

Upcoming Events