Repairing a Broken Glass Pipe: Is It Possible?

Maybe , there is no sure answer to that, its all depends on how bad it is. If it just a minor crack not leaking, a 3M clear tape could do that job easily. 

if you drop a bong onto a concert floor, and break it into millions tiny pieces.

might as well get a mob and clean it up, there is no gods well,not a   chance to get it repair or fix, unless you are locked up like in  a jail and bored to the die. Otherwise just leave it. Anyway on the other hand, I have already taught you how to fix a crack on a pipe.

If you pipe fit into the third category which is crack and leaking or something fall off, you may get a chance to repair it, depend on the thickness of the pipe, some American made pipes are super thick. You will have to get like superior jet flame to heat it up. If you have thin glass pipe just continue reads. Its very easy to fix it. 

Number four situations,  if you have a piece that has a small crack or a tiny area is broken off, then we can guide you to fix it. most the time the little bowl where you insert the downstem area are easy broke off, this is very common problem for alot people. Broken bowl inserts, or maybe a nose or dots on the bowl from the hand pipe,

There are a couple things you need before the repair processes. preferably  with some sort knowledge with glass blowing,

first thing, Safety First, you will need heat resist gloves, goggles, heat resist protect work apron,  then you need the tools. high temp torch, and torch stands, and work table. you can set it in your garage or backyard, I would high suggest not set it up in your house or next time something flammable . , its not very safe for beginners,

If you do have experiences for glass blowing, you can skip this, if you dont, here is some tools you will need to get it before next steps, first item is glassblowing lathe, this tool can hold the glass piece and rotated around, its must have item,  second item is Gas & Ventilation you need fire to heat up the glass right, you can get the can in local hardware stores. And a workbench ,you can lay out all the small tools you need for the job. A Kiln

Ensures the glass is properly annealed and cooled to prevent breakage as the glass cools. Also some Raw Materials like color glass rod or some small silver or marbles.  A torch to hookup the gas can and set on the workbench, a pair super thick cook over glove, when you doing it you dont want to burn you hands right,  safety goggles for the eye protection and Tungsten pick Esed to poke holes in glass, rake and drag glass in feathering, make small bubbles, marbling, and other detail work. You may need this to creat details on the pipes, or you may not,  those are all the tools before you start doing the repairs. 

 When you get all those items ready and set up, and make sure you double check it before turning on the gas, and recommend setting up those items in a Not fire hazard area, so you don't want to accidentally light up your house or someone else's restaurant and become broke. 

I would personally get life insurance before this.

Ok now  stop wasting time,  you turn on the gas and the torch starts to fire up . Changing the temperature of an object causes stresses in the material as it expands. The outside will heat first and expand while the inside remains cooler and smaller. The difference in expansion causes stress in the part. The faster you change the temperature the higher the stresses. Increasing the temperature slowly will keep the inside temperature very close to the outside temperature. This gives you the best chance of not having the crack expand and break the object.

so overall is just slowly heating up the part where it cracks,until the line disappear,

if you want to put two small piece together, its work the same, heat up to the point it close to liquify, and push them together, sometime if there is tube shape glass, you will have to reblow it,  make sure the end it not too hot when you reblow it, and always be extra cautious, blow glass is not easy job to do . 

anyway it is no guarantee just the best chance.depend on how solid the hand and how good the equipment you have.

also there is another cheap way to fix it.

there is hard glue that can glue about everything, metal glass or wood,  you have just try it all, see which one work the best