Soft Natural Rubber Lining

The standard polymers used for rubber linings consist of materials that are cross-linkable macromolecules which, on mixing with suitable reactants that form strong chemical bonds, change from a soft deformable substance into an elastic material. These polymers include natural rubber and its corresponding synthetic, c/s-polyisoprene, styrene-butadiene rubber, polychloroprene, butyl rubber, halogenated butyl rubbers, acrylonitrile-... 

Materials Handling Rubber lining for grabs, hooks and clamps. Wear resistant linings for chutes, hoppers storage bins etc. pulley rubber lagging for conveyor rollers. Soft natural rubber for wear resistance. Various rubber materials for roller coverings. 

Iron ore with a solid content of 25-30% in water is being handled in these feed launders. A feed launder is a mild steel, rubber lined chute through which ore slurry is conveyed to a concentrator tank. The velocity of the slurry is 0.66 m/s. As a result, 6 mm thick soft natural rubber compound of hardness 40 on the Shore A scale is well suited for this application. 

There is yet another type of lining called the Triflex lining. Triflex is a three ply, soft-hard-soft natural rubber construction. The soft rubber is compounded for maximum rubber to metal adhesion. The middle hard rubber layer, a flexible ebonite composition,... 

In the South African mining industry most processes for recovering precious metals, coal, minerals and diamonds are wet methods, involving the suspension of solids in water [1], In the control of such wet abrasive conditions in the pumping of fine particles size slurries, particle size separation in cyclones and in floatation cells, the choice of soft natural rubber lining is the most cost effective. 

This is red lead monoxide, used as in inorganic accelerator for the curing of soft natural rubber lining in an autoclave. High temperature curing leads to blooming of lead film, which is the chemical resistance layer, but impairs bonding with metal. 

Many moulded components are affixed on the rubber-lined surface such as anode sleeves in mercury cells used in caustic soda industry. These moulded components are either made from natural soft or ebonite rubbers or Neoprene rubber compounds. While moulding, the flow characteristics of the rubber compound and shrinkage need to be taken into consideration. Some aspects of mould designs are described next. 

Rubber linings consist of ebonite or soft rubber based on natural or synthetic polymers. They account for the largest group of materials used for surface protection in chemical plants. Synthetic elastomers are becoming more and more important since they have greater chemical and mechanical stability than natural materials and less susceptibility to mechanical damage. 

The degree of curing to which natural rubber is subjected will determine whether it is classified as soft, semihard, or hard. Soft rubber is the form primarily used as a lining material although some hard rubber linings are produced. Natural rubber is also used for lining pipelines. 

Typical applications for soft natural rubber linings include chemical storage tanks to handle phosphoric acid (37%), hydrofluosiUcic acid, alum, chlorides and sulfates of ammonia, cadmium, iron phosphoras and sodium, inorganic salts in gen-... 

Multiply natural rubber linings consist of three layers of rubber soft natural rubber/ hard natural rubber/soft natural rubber. The advantages of these linings are ... 

Rubber-to-Metal Bonding. In the Ebonit or hard rubber process [76], the bonding agent is a reaction product of natural or synthetic rubber with 30-40% sulfur, which is thermoplastic in character, adheres firmly to metal, and provides for good adhesion to soft rubber. This process is still in use today in the lining of vessels and, to a certain extent, in the manufacture of large-diameter rolls. 

Plastics and Elastomers. Common plastics and elastomers (qv) show exceUent resistance to hydrochloric acid within the temperature limits of the materials. Soft natural mbber compounds have been used for many years as liners for concentrated hydrochloric acid storage tanks up to a temperature of 60°C (see Rubber, natural). SemUiard mbber is used as linings in pipe and equipment at temperatures up to 70°C and hard mbber is used for pipes up to 50°C and pressures up to 345 kPa (50 psig). When contaminants are present, synthetic elastomers such as neoprene, nitrile, butyl. 

Mining and Ore processing Abrasion resistant linings for hoppers, chutes, cyclones, slurry pipelines, separators etc. Also bolt-in rubber wear plates for chutes and hoppers and conveyor rollers. Soft natural rubber for abrasion resistance. Hardness range 40 to 70°A... 

Chemicals, Chlor alkali. Paper and pulp, Fertilizers, Oil drilling and Pharmaceu ticals Chemical resistant linings for storage tanks, road and ship tankers, process vessels, pipelines, valves, pumps, filters, agitators, centrifuges, impellers, etc. Soft natural rubber or ebonite, neoprene, butyl and hypalon depending on operating temperature, and application. 

Power Generation Corrosion resistant linings for water treatment plant and cooling pipelines. Wear- resistant linings for coal handling plant, pulley rubber lagging for conveyor rollers etc. Soft natural rubbers and other synthetic rubbers... 

Water and Effluent Treatment in Nuclear and other chemical plants. Corrosion resistant linings for water treatment vessels and pipelines, pumps, valves, flowmeters, agitators, chemical dosing tanks, effluent tanks etc. Soft natural rubber or ebonite, EPDM, butyl, neoprene or hypalon. 

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