By the looks of the OD it will be a female part which has a fitting clamped over. It should be fine if you hammer the deformed end back into place as best you can.

Here is a thread I read with loads of information on how to clean a dpf.

DIY maintenance for the DPF... - 5Series.net - Forums

Look forward to hearing how you get on.

 

Cheers for that. Had a look and its not the one I have, but cleaning should be similar.

 

So im currently cleaning the dpf with a jetwash. I have oven cleaner, mr muscle, wd40, patio slab cleaner. Would any of these be ok to run through the dpf?

 

I wouldn't use anything that's caustic as it could damage the precious metals that line the DPF

 

The patio cleaner is hydrochloric acid, Is that caustic?

Its this stuff Cementone Brick & Patio Cleaner 5L - Toolstation

 

I now know the meaning of caustic. I wont use the acid then. Based on that should this be ok? Swarfega Multi Purpose Outdoor Cleaner 5L - Toolstation

 

I now know the meaning of caustic.

yep it dissolves stuff :hihi

that swarfega looks ok to me I think it a detergent