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 Initial Inspection
The initial inspection is done to evaluate the casing. The first and important step in the process of retreading is the detailed inspection of casing. This step guarantees that the casing is intact and in good condition. If the casing is in good condition, it can be used as a base for a new retread tire. Therefore it must be ensured, there are no injuries which might reduce the safety or performance of the retreaded tire.
Tyre Repair
This step is performed to remove all injuries identified during initial inspection and replace the material with structurally sound materials which will give new life to the casing
Buffing
The primary objective of buffing is to remove the worn out tread and prepare the surface for a new tread.
Skiving & Rasping
Skiving is performed to remove the loose rubber, ply and injury on the surface after the buffing operation. The skived surface should be made rough by rasping.
Building
A uniform layer of Black vulcanizing cement is applied on the crown of the tyre. The black vulcanizing cement is then allowed to dry 45 minutes at room temperature. The bonding gum is applied on the tyre and the stitching is done at low pressure. The tread rubber is applied on the bonding gum and the stitching is done at low pressure once and high pressure twice.
Eneveloping
In the tyre retreading process, the uncured cushion gum compound has to vulcanize while the pre-cured tread rubber has to be kept in position. Therefore the tire is placed into an envelope which presses the precured tread uniformly on the cushion gum and the casing
Application of Curing Bag, Flap and Curing Rim
The correct size of curing bag and flap is inserted into the tyre according to the tyre size. The purpose of the curing bag is to inflate the tyre during the curing process. The purpose of the flap is to increase the life of the curing bag, so that the flap absorbs the heat during the curing process. Without the flap the curing bag comes in contact with the heat which weakens the curing bag. The curing rim is then mounted on the tyre and the safety pin is locked.
Curing
Electric Curing chamber is an autoclave type device that applies specified heat and pressure over a period of time which causes the bonding layer in the built tire to cure and permanently adheres the new pre-cured tread to the prepared casing.
Final Inspection
The final inspection is done to ensure that the quality of the retreaded tyre is good.
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