Resources
Glossary.
The terms and abbreviations used on this site, each in a few plain words.
A
- Allowable stress (S)
- The stress a material may carry under the code at a given temperature, taken from ASME Section II, Part D. SA-516 Grade 70, for example, has 20,000 psi up to 650°F.
- APIAmerican Petroleum Institute
- The body behind API 660.
- API 660American Petroleum Institute Standard 660, Shell-and-Tube Heat Exchangers
- The standard for these exchangers in the petroleum, petrochemical, and natural gas industries. More
- Appendix 2ASME Section VIII, Division 1, Mandatory Appendix 2
- The rules for bolted flanges, used for the girth flanges of an exchanger. More
- Appendix 46ASME Section VIII, Division 1, Mandatory Appendix 46
- The appendix that lets a Division 1 vessel use Division 2 rules. More
- ASMEAmerican Society of Mechanical Engineers
- The publisher of the Boiler and Pressure Vessel Code and of the B16 flange and gasket standards.
- ASME Section II, Part D
- The part of the ASME code that gives material properties and allowable stresses.
- ASME Section IX
- The ASME rules for welding procedures and the qualification of welders.
- ASME Section VIII, Division 1
- The design code of PlutoHX: the Boiler and Pressure Vessel Code rules for pressure vessels, including shell-and-tube exchangers. More
- ASME Section VIII, Division 2
- The other division of Section VIII; PlutoHX uses its Part 4.16 for flanged joints and Part 4.18 for tubesheets.
B
- B16.5, B16.47, B16.20
- ASME standards for pipe flanges up to NPS 24, large diameter flanges from NPS 26 to NPS 60, and metallic gaskets. More
- Baffle
- A plate across the shell that makes the shell side flow zigzag across the tubes. The reference exchanger has single segmental baffles, cut about 22% of the diameter.
- BOMBill of materials
- The list of parts and materials of a design, with the material weight.
C
- Classic mode
- The form and settings way of working in PlutoHX, next to PlutoGen.
- Corrosion allowance
- Metal added on top of the calculated thickness, to be lost over the life of the part; 0.125 in in the teaching examples.
D
- Design by rule, design by analysis
- The two routes of Division 2: Part 4 and Part 5.
E
- EPCEngineering, procurement, and construction
- Firms that design, buy, and build plants for their clients.
F
- Fixed tubesheet exchanger
- An exchanger with both tubesheets fixed to the shell; the TEMA rear ends L, M, and N.
- Floating head exchanger
- An exchanger in which one tubesheet moves with the bundle; the TEMA rear ends P, S, T, and W, including split ring and lantern ring designs.
G
- Girth flange
- A large bolted flange that joins the main sections of the exchanger, such as the channel, the tubesheet, the shell, and the shell cover. More
H
- Hydrostatic test
- The pressure test of the finished equipment; under UG-99(b), at least 1.3 times the MAWP times the stress ratio.
J
- Joint efficiency (E)
- The factor for a welded joint in the thickness formulas, set by UW-12; 0.85 with spot radiography.
M
- MAWPMaximum allowable working pressure
- The pressure limit of the equipment at its design temperature under the code; 313 psi for the teaching shell with a 1/2 in plate.
- MDMTMinimum design metal temperature
- The coldest metal temperature the design is good for, with respect to brittle fracture; UCS-66 covers carbon steels.
N
- NDENon-destructive examination
- Tests that examine a part, such as its welds, without damaging it. PlutoHX lists the NDE a design requires.
- NPSNominal pipe size
- The size designation of a pipe or nozzle, such as NPS 24.
O
- ODOutside diameter
- The diameter over the outside of a tube, pipe, or gasket.
P
- Part UHX
- The part of Division 1 for tubesheets: UHX-12 U-tube, UHX-13 fixed, and UHX-14 floating tubesheet exchangers. More
- Pass partition plate
- The plate in the channel that divides the tube side into passes; it carries the pressure difference between adjacent passes.
- PCC-1ASME PCC-1, bolted flange joint assembly
- The standard for assembling bolted flange joints: the assembly bolt stress and gasket stress.
- PlutoGen
- The AI assistant inside PlutoHX. More
- PlutoVS and PlutoTK
- The other members of the Pluto family, for pressure vessels and for aboveground storage tanks; both coming soon. More
- PWHTPost-weld heat treatment
- Heat treatment of a part after welding. PlutoHX lists the PWHT a design requires.
S
- Saddles, fixed and sliding
- The two supports of a horizontal exchanger: one anchored, one free to slide as the shell grows with heat. More
- Shell side, tube side
- The two sides of the exchanger: the fluid around the tubes inside the shell, and the fluid inside the tubes. Datasheets mark them S and T.
T
- TEMATubular Exchanger Manufacturers Association
- The association whose Standards set the classes, types, and construction of shell-and-tube exchangers. More
- TEMA class
- R for petroleum and related processing, C for commercial and general process, B for chemical process.
- TEMA type
- Three letters for the front end, the shell, and the rear end, such as AET. More
- Tie rods and spacers
- Rods fixed in the stationary tubesheet that carry the baffles, with spacers between the baffles.
- Tube-to-tubesheet joint
- How each tube is held in the tubesheet: expanded, expanded and seal welded, or strength welded.
- Tubesheet
- The thick plate that holds the ends of the tubes and separates the tube side from the shell side. The stationary tubesheet sits at the channel; a floating tubesheet moves with the bundle.
U
- U-tube exchanger
- An exchanger whose tubes are bent into a U, with one tubesheet; the TEMA rear end U.
- UCS-66
- The Division 1 rule for the MDMT of carbon steels.
- UG-25
- The Division 1 paragraph on corrosion allowance.
- UG-27
- The Division 1 rule for shells under internal pressure. More
- UG-32, UG-34
- The Division 1 rules for formed heads and for flat heads and covers.
- UG-99(b)
- The Division 1 paragraph that sets the hydrostatic test pressure.
- UW-12, UW-20
- The Division 1 paragraphs for joint efficiency and for tube-to-tubesheet welds.
W
- WRCWelding Research Council
- Its Bulletins 107, 297, and 537 give the local stresses at nozzles from piping loads.
Z
- Zick
- L. P. Zick’s method for horizontal vessels on two saddles.
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