Achieving Efficiency in Abrasive Blasting William P. Nelson Schmidt Engineered Abrasive Systems Sponsored by: What is the Definition of “Efficiency”? Abrasive blasting is defined as a controlled.
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Transcript Achieving Efficiency in Abrasive Blasting William P. Nelson Schmidt Engineered Abrasive Systems Sponsored by: What is the Definition of “Efficiency”? Abrasive blasting is defined as a controlled.
Achieving Efficiency
in Abrasive Blasting
William P. Nelson
Schmidt Engineered
Abrasive Systems
Sponsored by:
What is the Definition of
“Efficiency”?
Abrasive blasting is defined as a
controlled erosion process whereas your
productivity is measured by how much
area is blasted, in what time frame and
by using how much abrasive
What is Abrasive Blasting?
“To combine the energy of compressed
air with a granular abrasive, which is
propelled to impact a surface in a
controlled, repeatable and predictable
surface preparation method.”
Enemies of any Air Blast
System
Insufficient air supply
Moisture
Pressure drop
Enemy #1
Insufficient Air Supply
You lose 1.5% of productivity for every 1 psi
reduction in blast nozzle pressure
(As stated in research by NACE)
Enemy #1
Insufficient Air Supply
NOZZLE
No. 4 No. 5 No. 6 No. 7 No. 8
Orifice Size
1/4”
5/16”
3/8”
7/16”
1/2”
CFM @ 100 psi
90
150
200
270
350
(All figures are approximate)
Enemy #2
Moisture
Increased operating costs
Increased material costs
Decreased operating efficiencies
Reduced productivity
Enemy #2
Moisture
How does water get into the compressed air?
All air contains moisture
As the air is compressed, any moisture in it will
also be compressed
As you compress the air/moisture, it heats up
Hot air retains moisture remaining a vapor
So…How do you remove moisture?
Enemy #2
Moisture
Convert moisture from a vapor to a solid (water droplets)
HOW?
By cooling the air you can then remove the moisture:
► By expansion (Moisture Trap)
► Use of radiator (ACS)
Once the air is cooled, you have to separate it:
► Demister Pad
► Centrifugal
► Absorption / Adsorption
Enemy #2
Aftercooler
System
Moisture
3” Air Inlet
1) 3” Outlet 2) 2”
Outlet
4) 1”
Outlet
Enemy #2
Moisture
Water Volume in Air
1500 CFM
200°
90°
Air Compressor
270
gal./day
90 Gal/day
180 Gal/day
75° Ambient Air
75% RH
Enemy #3
Pressure Drop
Nozzles
Hoses; Blast & Air
Restrictive Piping
Enemy #3
Pressure Drop
Nozzle Wear
Hoses & Set-Up
Enemy #3
Pressure Drop
Auto
Air
Valve
Enemy #3
Pressure Drop
High-Flow
Auto
Air
Valve
Proper Set-Up
Difference of Control
System Types
PRESSURE HOLD
NON-PRESSURE HOLD
Non-Pressure Hold System
Pressure Hold System
Fine Tuning an Abrasive
Blast System
Adjustments can be made to the following for
enhanced productivity:
Abrasive metering
Minimizing pressure drop & increasing air flow
Hose length, hose size, couplings
Nozzle size
Moisture in air
Achieving Efficiency
in Abrasive Blasting
THANK
YOU
Sponsored by: