CARCASS NOMENCLATURE

(1) COTTON/COTTON :

The Cotton/Cotton Belt constructions are described by specifying the number of plies & the type of fabric used in each ply of the Conveyor Belt. All Cotton fabrics will normally be one from the types specified in IS 1891 (Part- 1 )-1988 {Specification for Elevator & Rubber Conveyor Belting for General purpose applications). The Cotton Carcass Construction will therefore be expressed by say 6 ply fabric 42 oz. The breaking strengths of these finished Cotton fabrics are given in the following Table.

Type of Fabric	Breaking Strength	Weft
28oz	65	30
32oz	70	33
34oz	70	45
36oz	75	35
42oz	90	45
48oz	112	39

Fabric 34 oz is recommended for use in Elevator Belting only. The above fabrics are soft type except for 34 oz which is hard type. Warp Weft

(2) COTTON NYLON :

The Cotton/Nylon Belt Constructions are also described by specifying the number of plies & the type of fabric actually used in each ply of the Conveyor Belt. The fabric type is expressed by CN prefixing a number. This number represents the tensile strength of fabric expressed in KN/M Width of ply. For example 4 ply CN 100 represents a carcass having 4 plies each employing cotton Nylon fabric such that the tensile strength of the fabric in warp direction is 100 KN/M width per ply. The breaking strength of Cotton Nylon Fabrics is given below.

Cotton Nylon Fabric	Min Breaking Strength KN/M/Ply
CN 40	40
CN 50	50
CN 60	60
CN 70	70
CN 75	75
CN 80	80
CN 90	90
CN 100	100
CN 105	105
CN 130	130
CN 175	175

3. All SYNTHETIC FABRIC :

With the inception of Synthetic fabrics as reinforcement in Conveyor Beltings, the Carcass nomenclature is expressed as such that it indicates the minimum full thickness breaking strength of carcass In warp direction & the number of reinforcing plies e.g. 1250/4 denotes the Carcass made up of 4 plies of 100% synthetic fabric with minimum ultimate breaking strength of 1250 KN/M width of the belt. The various constructions with their minimum breaking strength in warp direction are

Carcass Construction	Minimum Breaking Strength KN/M/Ply	Carcass Construction	Minimum Breaking strength KN/M/Ply
200/2	200	630/4	630
250/2	250	800/4	800
315/2	315	800/5	800
315/3	315	1000/3	1000
400/2	400	1000/4	1000
400/3	400	1000/5	1000
400/4	400	1250/4	1000
500/3	500	1250/5	1250
500/5	500	1400/4	1400
630/3	630

NYLON/NYLON & POLYESTER/NYLON CARCASSES :

The Synthetic Carcasses are classified in three types. 1. General Duty (GD) 2. Moderate Duty (MD) 3. Heavy Duty (HD) These types have been expressed in their ascending order of lateral thickness for any given equivalent strength. Should belt type GD of a given strength fail to provide the necessary load support, choice is available to stipulate belt type MD. For still better load support requirements, type HD may be selected. The GQ type of belting is meant for light duty operations involving relatively light loads, short length convey- ors demanding relatively low belt strengths & where lump sizes or loading conditions do not impose heavy strain on the belting. The inter-ply rubber compound thickness in the belts is designed to provide longitudinal flexibility to operate on relatively small diameter terminal pulleys & with sufficient transverse rigidity to provide load support. The MD type Belts have higher interply thickness than those of corresponding GD type Belts & are designed to provide adequate load support & resistance from pinching between the flat & inclined idlers. The HD type Belts are specifically for heavy & extra heavy applications. The interply thickness & consequently the carcass thickness of these belts are substantially higher . than those of the corresponding construction in MD type Belts. These have been designed to meet very high impact conditions that are encountered in mining operations, Jong haul ore Conveyor & heavy duty Conveyors. The very high impact resistance of these beltings makes the use of breakers virtually redundant. Nevertheless, when required for extra heavy duty conditions of service, a specially designed Nylon breaker can be incorporated.