Water jetting Standards Flashcards
When viewed without magnification, shall have a matte (dull mottled) finish and shall be free of all visible oil, grease, dirt, rust and other corrosion products, previous coatings, mill scale, and foreign matter
A. WJ-1 Cleaning to Bare Substrate
B. WJ-2 Very Thorough Cleaning
C. WJ-3 Thorough Cleaning
D. WJ-4 Light Cleaning
A. WJ-1 Cleaning to Bare Substrate
When viewed without magnification, shall have a matte (dull mottled) finish and shall be freee of all visble oil, grease, dirt, rust, and other corrosion products excepty for randomly dispersed stains of rust and other corrosion products, tightly adherent thin coatings, and other tightly adherent matter. The staining or tightly adherent matter shall be limited to no more than 5% of each unit area of surface
A. WJ-1 Cleaning to Bare Substrate
B. WJ-2 Very Thorough Cleaning
C. WJ-3 Thorough Cleaning
D. WJ-4 Light Cleaning
B. WJ-2 Very Thorough Cleaning
When viewed without magnification, shall have a matte (dull mottled) finish and shall be free of all visible oil, grease, dirt, rust and other corrosion products except for randomly dispersed stains of rust and other corrosion products, tightly adherent thin coatings, and other tightly adherent foreign matter. The staining or tightly adherent foreign matter shall be limited to no more than 33% of each unit area of surface
A. WJ-1 Cleaning to Bare Substrate
B. WJ-2 Very Thorough Cleaning
C. WJ-3 Thorough Cleaning
D. WJ-4 Light Cleaning
C. WJ-3 Thorough Cleaning
When viewed without magnification, shall be free of all visible oil, greae, dirt, dust, loose mill scale, loose rust and other corrosion products, and loose coating
A. WJ-1 Cleaning to Bare Substrate
B. WJ-2 Very Thorough Cleaning
C. WJ-3 Thorough Cleaning
D. WJ-4 Light Cleaning
D. WJ-4 Light Cleaning
Unit area of surface is an area approximately
A. 6.0in^2
B. 9.0in^2
C. 12.0in^2
D. 4.0in^2
B. 9.0in^2
3 in x 3 in
Typically the nozzle should be held ________ from the surface.
A. 5-10 in
B. 2-5 in
C. 2-10 in
D. 6-12 in
C. 2-10 in
When removing heavy rust scale or old coatings, what degrees should the nozzle be in relation to the surface?
A. 90*
B. 45*
C. 50*
D. 25*
A. 90*
When removing mastics, what degrees should the nozzle be in relation to the surface?
A. 90*
B. 45*
C. 50*
D. 25*
B. 45*
At pressures lower than ____, loose rust, debris, and material in depressions and pits are removed, but the black iron oxide Fe304 (magnetite) remains. A matte finish is not achieved.
A. 10,000 psi
B. 20,000 psi
C. 34,000 psi
D. 36,000 psi
A. 10,000 psi
At pressures of ______, a uniform matte finish is obtained that quickly turns a golden hue unless an inhibitor is added or dehumidification is used. The black oxide is removed, but at a rate too slow to be considered practical.
A. 10,000 psi
B. 20,000 psi
C. 34,000 psi
D. 36,000 psi
A. 10,000 psi
At pressures of _____, uniform matte finish, quickly turns a golden hue unless an inhibitor is added or dehumidification is used. Black oxide, paint, elastomeric coatings, enamel, red oxide, and polypropylene sheet lining are removed, but with varying degrees of effectiveness.
A. 5,000 psi
B. 30,000 psi
C. 20,000 psi
D. 34,000 psi
C. 20,000 psi
At pressures of ______ to _______, uniform matte finish is obtained that quickly turns to a golden hue unless an inhibitor is added or dehumidification is used. Surface materials, including most mill scale, are removed.
A. 5,000-10,000 psi
B. 30,000-34,000 psi
C. 20,000-34,000 psi
D. 34,000-36,000 psi
D. 34,000-36,000 psi
List the advantages of waterjetting vs abrasive blasting
- Worker safety
- Worker air quality
- Respirator requirements may be less stringent
- No dust contamination or clean-up
- Friendly to hte environment
- Relatively cost efficient
- Requires less clean up
List the disadvantages of waterjetting vs abrasive blasting
- The surface must have a profile
- Equipment is very expensive
- Danger of UHP hose breaking
- Danger of injection into the skin or serious cuts
- Collecting and disposing of the contaminated water
- Proficient operators
