About to make a Compressor Silencing Enclosure?

[Rhysd1309]

Hi. After a few months of having a 5.5HP Honda Petrol driven compressor in my van, (powering my tyre machine) I don't think I can take the noise anymore! I think it's amplified being in such a small space. For the sake of my ears and customers, I was thinking about enclosing it into a bow made out of timber, mdf and acoustic foam.

Obviously, the main issue is going to be heat inside the box. On average, if I'm changing four tyres, the compressor stays running for around 40 minutes. I could of course switch it off when its at capacity.

The exhaust is directed out of the van through a hole in my wheel arch. I literally welded some 1/2 pipe and threaded the ends, then attached some elbows, to direct it straight out.

I would add hinges and toggle latches to the top side of the box, to allow for general maintenance and fueling.

I have made a few rough sketches. I was hoping for some constructive critism. I can instantly see a problem in that the fans would allow a lot of the noise past them.

On the right I have a baffle box, lined with carpet. The idea is for air to escape through the bottom right.

The inside of the box would be lined with acoustic foam. I was going to add two fans, drawing cool air from outside the box, blowing against the engine and the pump. Then, on the other side, have two fans sucking air from the engine and pump, expelling the warm air. Come to think of it, I suppose this contradicts the use of the baffles? And also would allow a lot of noise to escape?

This just shows the baffle side if the box, where I plan to mount a louvre panel or whatever they are called.


So in summary,

Would I be better mounting fans at this end?
Would it be better to mount the fans inside the box, without drawing air from outside?

Thanks for looking!!

 

[Rhysd1309]

Here's a revised plan, maybe replace the louvred panels with more fans??

 

[penfold]

I'd want a separate external air feed to the compressor, as compressing the warm air inside the box is pretty inefficient. The engine might benefit from external air as well.

 

[Robotstar5]

Has your van got a side door?, mount the compressor in the doorway and partition the access to the interior around it, you could create access/storage for other equipment you may need above it.

I've been on a couple of ambulances where the side door opens to allow access to grab bags, etc. but no access to the interior.

 

[DrNik]

Don't think you need such a detailed baffle to be honest, probably just one run would make a massive inprovement in noise

 

[brokenbiker]

the guy that does my bike tyres does exactly as robotstar suggests. he slides the side door open, starts the comp and genny, then shuts the door and its far quieter. jumps in the back and then he has the equipment running from the genny and air lines into the 'workshop' area. exhaust from both genny and comp are run through the floor and back to the rear, similar to the normal engine exhaust, air intake for the comp is mounted inside the 'work' area and has a filter on it.

he doesn't mind me knowing this and passing it on as he openly admits he copied someone else design with a few tweaks

 

[Rhysd1309]

Ahh the side door option would of been a great idea, but if anything I would have partitioned the back doors off. unfortunately though everything is already mounted, and as I do breakdown repairs aswell, I have a lot of tool boxes/ spring compressor stands/presses and stuff like that. (Also it gets very hot in the van and it is nice to work with that door open.

I think what I may do is box it off, would it then be beneficial to route the air filters to the pump and engine outside the van? Maybe route some pipe work through the roof?

 

[Rig Pig]

Don't forget to make them rain proof! Water in the intake or down the exhaust will wreck your gear. Try to separate the air intakes from the exhaust so you don't suck the fumes back in.

 

[Rhysd1309]

Don't forget to make them rain proof! Water in the intake or down the exhaust will wreck your gear. Try to separate the air intakes from the exhaust so you don't suck the fumes back in.

Cheers. The exhaust goes down through my rear wheel arch. And I was hoping to route the intake pipes maybe onto the roof, but make sure the filters point down so that the rain can't get into them.

I'm going to start building it within the next week or two, so I'll start to add a few pictures.