An airlock is specially designed to allow the co2 to escape through the liquid contained in the airlock. Therefor allowing nothing to get back in the fermentor (microbes, bacteria, spores, etc) Because the airlock is filled with liquid, the c02 bubbles out at a constant rate as the yeast ferments the sugars into alcohol. The only time an airlock will "blow up" is if there is not enough headspace in the fermentor, causing the yeast to foam towards the top and use the only exit it has (the airlock) and will cause your fermenting wine to foam out of the top. Never heard of an airlock "blowing up" so perhaps this is what you meant? Another technique includes attaching a length of tubing to the top of your fermentor and allowing the one end to sit in a bucket or bottle of water (essentially doing the same thing as an airlock) as to allow any yeast krausen or fermenting wine to collect in the bucket or bottle instead of clogging your airlock.