proceedings of the fourth us water jet conference - Waterjet ...

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Demonstration Tests Figure 14 shows examples of milled shapes in aluminum, titanium, and glass. The parameters used for milling these shapes are: Pressure (P) 172 MPa Waterjet diameter (dn) 0.356 mm Type of abrasive garnet sand Size of abrasive particles mesh No. 80 Abrasive flow rate (m • a) 7 g/s Traverse speed (u) 420 mm/s Figure 14. Examples of simple shapes milled with abrasive waterjets. The measured volume removal rates were: Titanium: 73 mm 3 /s Aluminum: 123 mm 3 /s Glass: 260 mm 3 /s Table 4. Comparison of Material Removal Rate Ranges for Different Materials with a 9 kW Abrasive-Waterjet Material (mm 3 /s) Aluminum 50- 300 Steel 40- 200 Cast Iron 50 - 250 Titanium 50- 250 Inconel 40- 200 Tungsten Carbide 0.1- 2 Alumina 0.2- 5 Silicon Carbide 0.2- 3 Graphite Epoxy 100 - 300 *Depends on alloy type or grade and traverse rate. Garnet mesh No. 80 at 7 g/s and 207 MPa pressure. 15
Table 4 shows the results of additional milling tests conducted in different materials. The data show different ranges, which depend on the AWJ parameters and the specific grade of material. For example, an order of magnitude difference can be observed in the milling of tungsten carbide depending primarily on the binder content. The case is similar for alumina ceramics, which depend on the purity percentage. COMPARISON WITH OTHER METHODS No detailed efforts are conducted here to compare quantitatively the cost of abrasive-waterjet cutting to other techniques. Such a comparison should be carefully conducted and should include many factors other than the cutting operation itself. For example, the required finishing of cuts made using thermal cutting techniques is an additional process that may not be needed if an erosive cutting technique, such as abrasive-waterjet cutting, is employed. The cost of equipment, environmental considerations and versatility of use are, of course, other factors that couple with the technical performance for a full economic evaluation. The data presented in this paper indicate the technical feasibility of abrasive-waterjet machining and how different parameters control the machining results. Specific advantages of abrasive-waterjets that may offset any economic disadvantages are as follows: • Ability to machine very hard materials • Ability to selectively machine multi-material composites • Minimal deformation stresses • Minimal thermal effects • Reasonable material removal rates • Omnidirectional machining • No heavy clamping needed for workpieces • No direct "hard" contact with workpiece • Ideal for automation and remote control Methods for three-dimensional metal shaping that may be replaced by abrasive-waterjet technology include the following: • Electrical discharge machining (EDM) • Electrochemical machining (ECM) • Chemical machining (CHM) • Ultrasonic machining (USM) • Abrasive jet machining (AJM) • Electron beam machining (EBM) • Laser beam machining (IBM) • Plasma are machining (PAM) 16
Page 1 and 2: PROCEEDINGS OF THE FOURTH U.S. WATE
Page 3 and 4: FOREWORD The U.S. Water Jet Confere
Page 5 and 6: FIELD APPLICATIONS- MINING Water Je
Page 7 and 8: Figure 1. Abrasive-Waterjet Nozzle
Page 9 and 10: N2 = ⋅ 2 d 2 j mav N = 3 N 4 Sett
Page 11 and 12: • Although reasonable correlation
Page 13 and 14: Effect of Traverse Speed Increasing
Page 15 and 16: Table 3. Material removal rate and
Page 17 and 18: Abrasive flow rate 7.5 g/s (maximum
Page 19: where u is the traverse rate in mm/
Page 23 and 24: this technique. The technique is al
Page 25 and 26: 12. Preece, C., editor, "Treatise o
Page 27 and 28: experiment was carried out to exami
Page 29 and 30: of changes in jet pressure, nozzle
Page 31 and 32: D = 0.0911 P 1.42 n 1.37 V −0.39
Page 33 and 34: Figure 8. Average Specific Energy V
Page 35 and 36: with the density of the material, o
Page 37 and 38: PERCUSSIVE JETS—STATE-OF-THE-ART
Page 39 and 40: This process of discharge modulatio
Page 41 and 42: has been demonstrated on all types
Page 43 and 44: 500 psig and 6,000 psig. Compressiv
Page 45 and 46: Figure 6. STATIC IMPACTS ON COMMERC
Page 47 and 48: not pursued because frequency, ampl
Page 49 and 50: 12. Ponchot, W.D., "Hydrodynamic Mo
Page 51 and 52: THEORETICAL ANALYSIS AND EXPERIMENT
Page 53 and 54: D.Rockwell, E.Naudascher, Thomas an
Page 55 and 56: Fig. 3 Flow model Hence we can comp
Page 57 and 58: amplitude decreases suddenly when c
Page 59 and 60: Where T: wave function period If we
Page 61 and 62: Fig.14 Variation of dimensionless r
Page 63 and 64: EXPERIMENTAL RESULT ANALYSIS (1) Th
Page 65 and 66: Fig.19 Amplification factor versus
Page 67 and 68: DYNAMIC CHARACTERISTICS OF WATERJET
Page 69 and 70: A piezoelectric transducer (Kistler
Page 71 and 72:
From the data obtained, it is clear
Page 73 and 74:
conjectured that this optimum signa
Page 75 and 76:
difference of impact forces with an
Page 77 and 78:
The pressure of the jet is not an i
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near the nozzle exit in the mixing
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etween 0.5 mm and 1.5 mm. Full- fie
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earlier observations that cavitatio
Page 85 and 86:
Obstructed Conical Nozzle The nozzl
Page 87 and 88:
CONSIDERATIONS IN THE DESIGN OF A W
Page 89 and 90:
An experimental mechanism was desig
Page 91 and 92:
horn and the modification of the st
Page 93 and 94:
ased on more detailed examination o
Page 95 and 96:
DEVELOPMENT OF CAVITATING JET EQUIP
Page 97 and 98:
hole, a total 23 minutes was requir
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from 1.5 to 4 ft to be cut. Other f
Page 101 and 102:
Table 2 Summary of CCPC Pavement Cu
Page 103 and 104:
All of the experimental modules wer
Page 105 and 106:
Figure 10. Effect of CAVIJET R cutt
Page 107 and 108:
HYDRO DEMOLITION - TECHNOLOGY FOR P
Page 109 and 110:
Figure 1. Air entrained concrete pr
Page 111 and 112:
TABLE II used a mean rating because
Page 113 and 114:
As work loads grew and costs escala
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inches deep of deteriorated bridge
Page 117 and 118:
Figure 6. Atlas Copco Conjet removi
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6. Total Ownership Cost Per Day $ 9
Page 121 and 122:
ABRASIVE-WATERJET AND WATERJET TECH
Page 123 and 124:
Commercial nuclear power plant deco
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Figure 3. Components of rotating no
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shroud and catching system designed
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Figure 9. Effect of abrasive size.
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alternative abrasive material. The
Page 133 and 134:
four arms leading to nozzle holders
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surrounding grout, they tended to r
Page 137 and 138:
12. Hashish, M. “Steel Cutting wi
Page 139 and 140:
Figure 1 Kerf test stand pressure v
Page 141 and 142:
Figure 3 Kerf area versus standoff
Page 143 and 144:
The ratio of kerf depth to width or
Page 145 and 146:
where: x c = u o d o ( ) (1) 4v e l
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Depending on the rock type γ can v
Page 149 and 150:
CONICAL WATER JET DRILLING W. Dicki
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feed line. A conical cutting fluid
Page 153 and 154:
A second series of tests at the ful
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Figure 8. 6061-T6 aluminum cut with
Page 157 and 158:
serves to reduce tool wear (8). It
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Traverse speed is the velocity of t
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Figure 4: Diagram illustrating the
Page 163 and 164:
The picture changes dramatically wh
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Analysis of the residuals of these
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5. Hood, M., "Cutting Strong Rock w
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hundred feet-per-second. At these v
Page 171 and 172:
Figure 1. Typical Nozzle Configurat
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Figure 5. Expanded Signal from an I
Page 175 and 176:
where: V w = water velocity F = mea
Page 177 and 178:
HYDRO-ABRASIVE CUTTING HEAD—ENERG
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Figure 3. Percentage of initial abr
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Figure 6. Location of optimum recei
Page 183 and 184:
WATER JET ASSISTED LONGWALL SHEARER
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• reduction of the proportion of
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The conversion set for the shearer
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into account. As far as possible no
Page 191 and 192:
gal/yd 3 ). Another important influ
Page 193 and 194:
At approximately 2 m/s (393 fpm), a
Page 195 and 196:
Proceedings of the 8th Internationa
Page 197 and 198:
κ = permeability of rock at atmosp
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operating parameters (P. V tr , etc
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κ = permeability at 1 atm. pressur
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was substantial gain in the depth o
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Figure 9. Plot of exposure rate aga
Page 207 and 208:
For nozzle C2, a = 0.5 x 10 4 and b
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204
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Deep drilling or slotting requires
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imparted by an air motor coupled to
Page 215 and 216:
Conventional rotary or percussive r
Page 217 and 218:
A RELATIVE CLEANABILITY FACTOR A. F
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Relation [6] was used to derive the
Page 221 and 222:
which has been observed for much of
Page 223 and 224:
As part of a project to develop the
Page 225 and 226:
Figure 1. Cost per square foot clea
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Abrasive Feed Rate The effect of ab
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Figure 4. Total cost per square foo
Page 231 and 232:
3. Barker, C. R.; Mazurkiewicz, M.
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For our purposes here, we will lump
Page 235 and 236:
Surface condensers can be cleaned b
Page 237 and 238:
Some Powerlance customers have 20,0
Page 239 and 240:
system could be designed that was o
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236
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ROTARY WATERBLAST LANCING MACHINES
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Motors and Gearing An advantage of
Page 247 and 248:
The DuPont Company in LaPlace, Loui
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Fig 3 Heavy duty Rotary Lancing Mac
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D L - lower diameter of through hol
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Figure 1. A - single-pass, rough ke
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The erosion process is stochastic i
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three dimensional controlled erosio
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This can only be regarded as a simp
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approximately zero. Time constant T
Page 263 and 264:
Figure 12. Transients of HAJM cycli
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T A = (f, h o, p, s o, f o, c, . .
Page 267 and 268:
SURFACE FINISH CHARACTERIZATION IN
Page 269 and 270:
FIG. 2 Force Sensor Designed for Cu
Page 271 and 272:
system can be used in the developme
Page 273 and 274:
Figure 8 Cutting Force versus Cutti
Page 275 and 276:
nearly at the center of the ceramic
Page 277 and 278:
ABRASIVE WATERJET CUTTING OF METAL
Page 279 and 280:
Figure 1. Experimental setup, inclu
Page 281 and 282:
Figure 3. Scanning microphotograph
Page 283 and 284:
Figure 8. Effect of cutting speed o
Page 285 and 286:
a. Scanning microphotograph, lOOOx
Page 287 and 288:
c. Silicon image 1000x Figure 16. S
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