6.3.5 Large Bulk Handling Conveyor Chain (CT)
Large conveyance: The steel industry, container conveyance
Application Example
Large Bulk Handling Conveyor Chain (CT) is used in the steel industry to convey hot steel coils (up to 700°C) as well as slabs or other heavy objects, such as containers. This chain is very strong. It can convey several coils, which can weigh up to 45 ton/coil.
Construction and Features
CT Chain is used in pairs, and heavy objects are conveyed directly on them. Standard large pitch chains do not have enough capacity to support the extremely heavy loads (the limiting factor is the roller). For that reason, special cylindrical bearing rollers have been developed. They combine a high allowable load for the roller with low coefficient of friction. The coefficient of friction is 0.03, which is one-third to one-fourth the coefficient of friction of standard large pitch conveyor chain in normal temperatures.
Figure 6.20 and Table 6.4 show the structure, dimensions, and functions of this chain.
A coil can be conveyed on its side or straight up. When the coil is on its side, you can use the chain as shown in Figure 6.20. Special attachments need to be used when conveying a coil straight up. Figure 6.21 shows examples of Large Bulk Handling Conveyor Chains with attachments for conveying round objects, and one for curved conveyance.
Figure 6.20 Large Bulk Handling Conveyor Chain (CT)
| Chain No. | Pitch (mm) | Roller Dia. (R) | Link Plate Height (H) | Max. Allowable Roller Load (kN) | Max. Allowable Load (kN) | |||
|---|---|---|---|---|---|---|---|---|
| CT 60 | 300 | 400 | 500 | 125 | 171 | 29.4 | 83.3 | |
| CT 90 | 300 | 400 | 500 | 135 | 182.5 | 35.3 | 126 | |
| CT 130 | 300 | 400 | 500 | 150 | 195 | 42.2 | 181 | |
| CT 160 | 400 | 500 | 600 | 175 | 227 | 55.9 | 224 | |
Figure 6.21 Large Bulk Handling Conveyor Chain (CT) with Special Attachments
Sprockets
Large Bulk Handling Conveyor Chain requires special sprockets. They must operate at low speeds (less than 15 m/min.) and usually have six to eight teeth, which keeps the diameter small, and cost down.
Technical Trends
The coils are sometimes very hot, and are frequently transported through a heat chamber. For these applications, the chain must be heat-resistant. In one specific case, steel slabs were placed directly on the chain in five piles. Each pile weighed 80 ton, and the surrounding temperature was 900°C. In extreme situations like this, consult the manufacturer.
