Black Z Eddie
Member
When an air tool like an impact wrench says it's 90 PSI Max, does that mean under load? Or at the air compressor regulator?
Thanks.
Thanks.
Impact Wrench 90 PSI Max Meaning
- Thread starter Black Z Eddie
- Start date
eschoendorff
Well-known member
See.... I thought it meant under load. If you set your regulator to 90 psi and pull the trigger, you will see taht the pressure goes down to bout 70 psi or so. If you set your regulator at 120, when you pull the trigger, the actual pressure is at about 90-100 psi and you get MUCH better performance.
Charles (in GA)
Well-known member
You should not be seeing that much pressure drop when you demand air. Sounds like your regulator cannot keep up with it. The gun is rated at 90 psi, period, they don't expect you to have pressure drops like that.
The higher pressure at startup won't hurt anything, set it up to 90 psi under load and go with it. I actually run mine at about 105 - 110 psi all the time but I only see about 5 lb drop at the regulator (cheap regulator) and probably another 5 lbs or so at the end of the hose.
If you are really curious, tee in a gauge at the gun temporarily and set the regulator to whatever it takes for the gun to get 90 lb while under load, at the gun, that is how its rated.
Charles
Uncle Buck
Banned
Don't forget to take into account pressure drop from the compressor to the tool. The smaller the air line, and longer the run the greater % of pressure drop you will experience. That is one good reason to always use a 3/8 air hose at minimum. The 1/2 was always a bit bulky for my liking.
Really? That sounds like a good next project for me.
So when you hit the trigger, you only see a 5 lb drop?
I need to check mine. I always thought the drop was a function of the regulator, common to all regulators.
OP
Black Z Eddie
Member
I get a lot of pressure drop on my air compresser regulator when the gun in under load. It's just a little 10 gallon 2.5 hp. As eschoendorff describes also, mine drops from 90 to 70-75 when under load. So I set the regulator to 115-120 to get the 90.
Sounds like I'm safe with my assumption that the "90 psi max" refers to the actual pressure when under load. I just didn't want the tool blowing up in hands and face.
Sounds like I'm safe with my assumption that the "90 psi max" refers to the actual pressure when under load. I just didn't want the tool blowing up in hands and face.
I get a lot of pressure drop on my air compresser regulator when the gun in under load. It's just a little 10 gallon 2.5 hp. As eschoendorff describes also, mine drops from 90 to 70-75 when under load. So I set the regulator to 115-120 to get the 90.
Sounds like I'm safe with my assumption that the "90 psi max" refers to the actual pressure when under load. I just didn't want the tool blowing up in hands and face.
You ran a impact wrench with a 10 gallon 2.5 hp compressor ... wow ...
kartracer55
Well-known member
- Joined
- Jun 21, 2005
- Messages
- 5,317
All the air tools at work, with the exception of lock release on the alignment rack and the wheel lift for the dyno rollers run between 120 and 140 PSI, unregulated. Guns hold up fine. Biggest problems with guns are the hammer case screws breaking from being dropped.
Jim
Jim
Same thing at my work. Unregulated air to everything, which is in the 120-140range.
the intimidator
Well-known member
We alway's ran the gun's and other air tool's at 125 psi at the regulator when I was at the shop we never had any failures besides the little lock rings that lock the socket on would get buggerd up and not realise the socket without a hammer or pair of channel locks stupid little things those were the funny part was the snappy guy would not just give a couple of them out to put in the box so when it happend on tuesday and he came on friday you were stuck until then.
Charles (in GA)
Well-known member
I take it that under load (with reference to CFMs or PSI) means that the is gun putting out the max rated torque. Depending on the compressor, regulator, filter, hose, air couplings, you may not be able to maintain 90 psi at the gun inlet, no matter how much pressure you put out at the regulator.
Charles
Charles
The pressure is actually meant to be measured at the inlet of the tool (between the quick disconnect and the tool) with the tool running free speed. If it is measured upstream from that you are not accoutning for any pressure drops due to length of hose or number of fittings etc. If the pressure is not measured with the tool running then you are just measuring the static pressure at the compressor. Make yourself a T with a ****** on one side that will screw into the tool, a Q.D. on the other and a gage coming off the T (preferrably on a short section of hose otherwise vibration will make it tough to read) This is a good tool to have to check what pressure your tools are running at.
katit
Well-known member
checked yesterday. Husky 1/2 impact. Husky pro standup compressor. 120 at regulator - 90 at regulator outlet with impact under load (tightening bolt)
I was doing 90 static all the time. No wonder I couldn't get some of the bolts out with it
I was doing 90 static all the time. No wonder I couldn't get some of the bolts out with it
Handyman163
Well-known member
I know this is an old thread, but I've been dealing with this issue lately. Cheap regulator causing my air tools to not work properly. I removed the regulator altogether, and got the compressor set to run up to 120psi, then kick on around 90psi. I've been running my tools unregulated on my 21 gallon tank. This lets me get two wheels off of my pickup and then back on before I get down to the point where the compressor kicks on, so I'm not running my impact wrench at 120 for very long. I'm trying to figure out whether it's worth it for me to invest in a good higher flowing regulator. My compressor is rated at 4.9 SCFM @ 90 psi, and I mostly air up tires, use the impact wrench for brake jobs and tire rotation, and occasionally a small nail gun. My nail gun acts fine driving 1-1/4" finishing nails even on 1/4" plywood at 110psi.
For comparison after reading this thread, I put my old regulator in-line at the tank, and at the impact wrench. At the tank, the most I could dial it up to was 100psi (tank was at 120psi), when I squeezed the trigger on the impact gun, pressure on the regulator gauge dropped to 60psi (a 40psi DROP!!!), and the gun was running audibly slower than normal - useless! At the gun, the pressure dropped from 100psi to 50psi. Wow, this really is a crappy regulator. It's only good for my stapler/nailer, obviously - with the nailer it dropped from 100psi to 80psi each time the trigger was pulled.
After reading this thread, would it be safe to assume that for the amount I use my impact wrench and other tools (once a month or so) that running them unregulated on no more than 120psi shouldn't hurt a thing?
For comparison after reading this thread, I put my old regulator in-line at the tank, and at the impact wrench. At the tank, the most I could dial it up to was 100psi (tank was at 120psi), when I squeezed the trigger on the impact gun, pressure on the regulator gauge dropped to 60psi (a 40psi DROP!!!), and the gun was running audibly slower than normal - useless! At the gun, the pressure dropped from 100psi to 50psi. Wow, this really is a crappy regulator. It's only good for my stapler/nailer, obviously - with the nailer it dropped from 100psi to 80psi each time the trigger was pulled.
After reading this thread, would it be safe to assume that for the amount I use my impact wrench and other tools (once a month or so) that running them unregulated on no more than 120psi shouldn't hurt a thing?
It will be fine, after the hose and quick disconnect the pressure is probably not much above 90, if at all.
mrshaun
Well-known member
optimal performance is at 90 psi. Lots of shops run higher pressure and get better performance. I have guns in shops that the pressure is outrageous ( rotary screw compressors on the military base ) and the guns seem to do just fine and no one complains.
WHen the air pressure is low, is when guys say the tool is a piece of junk. even if you tell them they need more air, they still argue. some people do not understand how things really work.
WHen the air pressure is low, is when guys say the tool is a piece of junk. even if you tell them they need more air, they still argue. some people do not understand how things really work.
WickedGTP
New member
I'm having this same issue except its on my grandfathers air compressor so far all I know is that it's 20gallons but fairly old. I'm currently tearing my motor apart and I can't seem to get the tank to stay at 90psi when the compressor kicks on it will raise up to 120 but as soon as i start using my impact the pressure fluctuates from 60-90. Are the regulators a general item for compressors or are they brand specific? Could that be my issue?
Thanks in advance,
Bryan
nissan_crawler
Well-known member
a good regulator is a good regulator. You obviously have to match fitting size, but other than that, it's irrelevant.
As for the rest, I would set it at 90 p.s.i. running. Also, going a bit over isn't going to hurt a quality gun, especially at a homeowner level of use. If you're running 140 p.s.i. to it changing tires and running one non-stop every day...you'll probably see a difference. At a regular shop, or home use, doubtful.
As for the rest, I would set it at 90 p.s.i. running. Also, going a bit over isn't going to hurt a quality gun, especially at a homeowner level of use. If you're running 140 p.s.i. to it changing tires and running one non-stop every day...you'll probably see a difference. At a regular shop, or home use, doubtful.
WickedGTP
New member
Do you know where I could find a good regulator?
Thanks, Bryan
Thanks, Bryan
bmxr4life87
Well-known member
we have 175 psi out of our large compressor at the shop which is about 150psi at the end of our air hoses and the only air tool to blow up so far was a pneumatic caulking gun that was rated 50psi MAX haha impacts grinders and drills all holding up just fine but we have to have such high air pressure for bigger truck tires that require 110psi
Moose-LandTran
Well-known member
One place i worked we were getting 120+psi at the end of the airlines. It made the guns a bit fierce. Was good though.
caper
Well-known member
Most truck shops I worked at run about 175psi,unregulated with 1/2" hoses.My gun is 15yrs old and still going strong.I wouldn't worry about putting 125psi into a homeowners gun a couple times a month.