Applications
6.1.3 Construction and Features The structure of large pitch conveyor chain is shown in Basics Section 1.1.
6.1.3.1 Shape Features (1) Side plates are straight.
(2) Because the radius of the side plate end is greater than half of the side plate height, the corner of the engaging side plate will rise slightly when the chain joint engages the sprocket. This may cause interference with objects conveyed directly on a chain equipped with an S-roller. (The roller diameter is less than the height of the side plate.) (3) The end of the pin (opposite to the head of the pin) is equipped with a cotter hole for a T-pin. This arrangement allows easy assembly or disassembly of chain links. (4) The pin has a swell neck at one end, and the cotter side can either be double flat or have a D-shape. Accordingly, side plates have full round pin holes, and D-shaped or double-flat pin holes. (5) There are three types of rollers available: R, F, and S (M, N). The F-roller is a feature of large pitch conveyor chains, since they are useful in guiding the chain on the rail. However, the flange wears against the rail, and therefore, should only be used when the chain is lubricated, or when the conveyed material acts as a lubricant. Additionally, F-rollers should be avoided where heavy loads are conveyed, otherwise the flange may wear quickly or break. As a rule, S-rollers are used to reduce sprocket tooth wear due to smooth engagement with the sprocket, but are not suit- able for rolling conveyance. (6) R- and F-rollers have small-diameter hubs on their sides.
6.1.3.2 Function Features (1) High rigidity.
Large pitch conveyor chains are designed to carry heavy loads and endure rough loading. Of course, there are limits to the chain’s integrity, and it is important to consult the manufacturer for details. Let us check the chain’s resistance to bending. The following formula shows the relationship between bending moment, M, and stress:
M= s Z = 1/6 3s3 H 3 t 2 s : stress on side plate H: side plate height t: side plate thickness
Using the equation, let’s compare the effects of side plate thickness (t) on chain rigidity when tensile strength, side plate height (H), pin diameter, and bushing diameter are held constant.
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