Blower Damage Ad Infinatum And The Business End Of A Hg. Gauge.
First off, tell me what type of blower are you using? you have essentially told us little or nothing.
Do you have a picture of the damage? Is it possible there is a flap check valve that is unseen in the system? If it is stuck open it will allow flow of material into the blower?
blowers are dumb just like rocks look for the obvious but suspect
particle contamination in the air stream. They will run until they can not run anymore. under load or no load.
1. holes in filter system.
a. too small a blower for the job intended.
2. Poor substandard rebuild parts, cracked lobe castings, reuse of old parts -a big no no.
a. improper calibration of regulator by not using a delaval milk house gauge to verify air flow in vacuum mode.
improper installation/alighnment.
b. you can not rely on a dial gauge in the pipeline alone.
c.relief regulator not relieving with the result being overheating and bearing failure.
3. maintenance or lack their of, over greasing, lack of oil in gear case. bearings installed backwards,unsealed bearings used in place of sealed bearings, blower seals damaged at installation or as they age, defective pressure regulator/relief valve.
a. if a rotary lobe blower is used the the lobe must be positioned exactly 90 degrees opposite the other lobe before the gears are attached.
b. if the gears are not secured they could shear the keys and then fail the blower ruining it entirely.
4. too high a blower speed -rpm from electric motor- is it direct drive shaft to shaft or belt driven?, what is the RPM?
a. too low a blower speed.
Teus if I missed something my humble apologies. ■
Material In Blower
I would bet your problem is caused by leaking filter bags. Bag filters need to be maintained as with all mechanical devices.
Michael Reid. ■
Re: Vacuum Blower Issues/ Material In Blower
Your problem could well be the filter bags.
Most filter bag materials operate on a depth filtration principle. This means the fabric has a relatively open weave and initially you get a relatively high level of powder slippage through the bag material until the fabric fills with dust powder and the filtration efficiency then improves.
If this is your problem, going to a surface filtration type fabric, would help. I think PTFE (Goretex) coated fabrics operate much more in a surface filtration way and allow less slippage but you really need to talk to a filter supllier to confirm this, I am sure they will have options for different materials and can advise on the relative benefits.
The other way to approach it is to have a back up filter behind the main filter. These are normally a cartridge type filter (cartridge filters normally operate in surface filtration mode) and are common on closed loop conveying systems. i would never install a closed loop system without one because of this problem. The downside of his on your system though is that there will be an additional pressure drop across the back up filter. ■
Re: Vacuum Blower Issues/ Material In Blower
dear Mr RJB324
If you find material in your blower, which should not be there, you certainly have an air-material separation problem.
Is the blower blocked with material or worn out by material dust, causing a too big gap between rotors and housing?
Is the blower venting dusty air to the atmosphere?
In case I understand your installation description correctly, you have a cyclone and a filter receiver in series.
The filter has to keep the material away from the blower.
Focus on this part of the installation first.
Whether your complete installation is properly designed, is very difficult to judge on the given info.
Check that also.
For more in depth advice, you can come back to the forum with more info, s.a. material, installation data, blower data, performance parameters, tons/hr, vacuum, temperatures, etc.
succees
teus ■
Teus
Vacuum Blower Issues/ Material in Blower
Guys,
We are having major issues with our vacuum airveying system. The blower keeps getting destroyed because of feed carryover. The system has not been modified in years and also no modification to feed has occured. The system pulls material from bins through a cyclone with a R.A. on the bottom of it. The carryover air then goes through a Filter receiver with a knife gate valve on the bottom of it. The filter receiver has a Pulse-air system to clean the bags.
What issues from your past experiences with vacuum systems could be the root cause for product carryover into the vacuum blower. Please tell me if any of the following could cause this:
- pluggage in airvey piping from the bin through the cyclone
- leaking from the rotary airlock on the bottom of the cyclone
- leaking from the manual knife gate valve on the bottom of the filter receiver
- incorrect functioning of the pulse-air system for bag cleaning
- air leaks in airvey piping
- mechanical issues in the Filter Receiver
- air flow too much for cyclone to handle (increase in cyclone velocity decreases collection efficiency over a certain velocity)
Please check my causes and add anymore you see.
Thanks. ■