Are Tyre Repairs Safe?
Which Repair Is Best When You Have a Flat Tyre?
It is most likely that a punctured tyre must be replaced. However, it may be possible to repair the tyre. If your tyre can be repaired, there are three common types of tyre repair that might be used.
Tyre Repair #1: Plugging
A plug is the simplest of tyre repairs and the fastest. When a technician makes this type of tyre repair, they create a plug with a small piece of leather, coat it in rubber adhesive, and plug the puncture with it.
As you drive on the repaired tyre, the heat created vulcanises the rubber adhesive and it hardens to seal the puncture. It is possible to make this type of repair without removing the tyre.
There is a downside, though. The plug must fit exactly, so a strangely shaped hole will be difficult to plug. The plug may work itself loose and the repair becomes ineffective.
Tyre Repair #2: Patching
Patching is an internal repair technique.
A square of rubber is backed with rubber adhesive and glued to the puncture on the inside of the tyre. The adhesive vulcanises as the tyre heats up during driving, and this hardens the repair. Because the tyre must be removed, this repair takes longer and is more expensive than plugging. However, it is also more stable.
Tyre Repair #3: A Plug/Patch Combination
A plug/patch combination is the strongest of the three types of tyre repair. It is sometimes called a mushroom repair and seals the puncture from inside to the outside.
A ‘tail’ is added to the rubber patch and threaded through the puncture hole to act as the plug. The tyre must be removed to make the repair, and while this type of repair is the most effective it is also the most complex. It takes longer than either of the other two types of repair and is the most expensive.
How Is a Combination Plug/Patch Tyre Repair Made?
Making a combination plug/patch tyre repair is a complicated process. It’s not like making a repair on a bicycle tyre! There are many steps involved:
- Remove the tyre and inspect
The tyre must be inspected thoroughly to make sure that it can be repaired.
- Mark up the damage
The damage is located and marked, and foreign objects are removed.
- Drill from the inside
The puncture hole is drilled from the inside to make it uniform.
- Drill from the outside
The puncture is drilled from the outside until no resistance is felt.
- Clean the area of damage
The area of damage is thoroughly cleaned to around 1cm to 2cm larger than the size of the repair patch using pre-buff cleaners and a repair scraper.
- Mark and clean internally
The repair patch is held on the inside of the tyre where it will be fixed, and the tyre is marked up around the patch. The area marked is buffed to around ½cm larger than the repair patch using a domed buffing rasp. It is essential that the area is flat.
- All dust is removed
All dust is removed, and the repair area is cleared of wire and fluffed cords.
- Vulcanising accelerator is added
A vulcanising accelerator is added to the puncture channel and the buffed patch area.
- Plug the puncture
The patch’s tail is threaded through the puncture hole.
- Pull the tail through
The tail is pulled from outside the tyre so that the patch sits tight and flush internally.
- Flatten the patch
The patch is rolled from its centre to its edges using a corrugated tyre stitcher. This removes air bubbles and ensures complete contact with the buffed interior of the tyre.
- Seal internally
The repair patch and plug base are sealed with an inner liner sealant.
The tyre is remounted onto the wheel and inflated to its correct pressure.
- Finish off
To finish the repair, the plug is cut flush with the tread of the tyre.
Should You Repair a Tyre?
As you can see, there are three ways in which a tyre might be repaired. If you have a flat tyre, you must take it to a tyre shop to be inspected. The tyre specialist will tell you whether it can be repaired after first assessing the damage to the tyre. If a repair is made, you should remember that a repaired tyre is never as strong as a new or undamaged tyre.
If you are in Brisbane and have a flat tyre or a tyre that keeps losing tyre pressure, contact Darra Tyres today. Don’t be sorry, be safe.
Keeping your family and fleet safe on the road,