COMMON STRUCTURAL SHAPES
The following is an overview of structural metal shapes commonly used in the fabrication of weldments. Figure 6.2 and Figure 6.3 show these shapes. Table 6.2 describes how size specifications are given for common shapes.
When ordering structural metal, reference is made to manufacturers’ catalogs. These catalogs contain tables with a listing of the sizes available for various shapes, including the weight per linear foot.
FIGURE 6.2 ■ Common structural metal shapes. |
FIGURE 6.3 ■ Structural beam shapes. |
Sizes listed for many structural shapes are only nominal sizes. This means that an approximate size, rather than the actual size, is represented by the catalog size designation. For example, the designation of a wide - flange beam (W) is shown as W10 X 112. The letter “W” signifies a wide-flange beam, the number 10 indicates it has a depth of 10", and the figure 112 signifies a weight of 112 pounds per linear foot. However, the actual size of the depth dimension is 11[1]/8", which is one of the items of information provided in the table for wide flange beams. Refer to Appendix 2.
Structural beams are classified into four shapes:
1. Standard beams (or I-beams) identified by the letter “S.”
2. Wide-flange beams, identified by the letter “W.” When formed by welding, the identification is “WW.”
3. Miscellaneous beams identified by the letter “M.” These beams may also be identified as “Jr.,” “H,” or “Light Beams.”
4. Bearing pile beams, identified by the letters “HP”
The material of which the structural shape is made is identified on the drawing or in the specifications. Sample notes are as follows:
NOTE: ALL 2'' SQUARE TUBING TO BE WELDED COLD-ROLLED STEEL
MATERIAL: ALL RECTANGULAR TUBING TO BE SEAMLESS COLD-DRAWN STEEL
Pipe is also sized by applying a schedule number as a part of the size specification. There are 11 schedules that are commonly used: 5, 10, 20, 30, 40, 50, 60, 80, 100, 120, and 160. The schedule numbers represent the strength of pipe and refer to its wall thickness. A study of the pipe schedule table in Appendix 3 will show that the higher the schedule number, the greater the wall thickness of the pipe. Note that the table uses the abbreviations E. H. and DBLE. H., which signify extra heavy and extra extra heavy in place of extra strong (x-strong) and extra extra strong (xx-strong). When specifying certain pipe sizes, schedule numbers may be used in place of standard, extra strong, or double extra strong designations. Examples of pipe sizes using pipe schedule numbers follow:
Example 1:
2" schedule 40 X 10' welded wrought steel pipe in place of 2" standard welded wrought steel pipe X 10'
Example 2:
3" schedule 80 X 10' seamless wrought steel pipe in place of 3" extra strong seamless wrought steel pipe X 10'
Standard abbreviations that are used to identify the kinds of metal are given in Table 6.3.
Note that pipe sizes may also be designated in metric units (mm). Refer to Appendix 4, page 392.
Alloy Steel |
ALSTL |
Hot-Rolled Steel |
HRS |
Aluminum |
AL |
Low-Carbon Steel |
LCS |
Brass |
BRS |
Magnesium |
MAG |
Bronze |
BRZ |
Malleable Iron |
Ml |
Cast Iron |
Cl |
Nickle Steel |
NS |
Cold-Drawn Steel |
CDS |
Stainless Steel |
SST |
Cold-Finished Steel |
CFS |
Steel |
STL |
Cold-Rolled Steel |
CRS |
Tool Steel |
TS |
High-Carbon Steel |
HCS |
Tungsten |
TU |
High-Speed Steel |
HSS |
Wrought Iron |
Wl |
1. What thickness limit classifies metal as being 13. What is the size specification of the angle iron
sheet? below?
2. What is the decimal size of 14 AWG sheet?
4. What specifications are necessary for ordering a standard size of sheet iron?
14. Which dimension(s) determine(s) the size of this S-beam?
7 |
5. What other item of stock can be measured with a sheet metal gage?
6. How is plate thickness specified?
7. Which is more accurate in size, hot-rolled or cold-rolled stock?
8. How can hot-rolled stock be distinguished from cold-rolled stock?
15. Why is a weight specification applied to an S-beam?
16. a. What terms are applied to the parts of the wide-flange beam represented by letters E and F?
D E F |
9. What is a piece of й" X 1" X 6" long stock commonly called?
10. How is the size of round steel or cast iron determined?
11. How is the size of hexagon steel determined?
12. What is the size specification of this angle iron?
b. Identify the sizes represented by the letters A, B, C, and D.
A
B
C
17. Sketch the symbols for:
a. Square tubing
b. Rectangular tubing
18. What is the difference between a standard
S-beam and a wide-flange beam?
19. What is the difference between a wide-flange beam and an M-beam?
20. What dimensions do S-beams, wide-flange beams, and M-beams have in common?
21. What are the similarities between an HP beam and a wide-flange beam?
22. Write the size specification for a piece of 3" hollow, square tubing /4" thick by 12' long.
23. Explain the following abbreviations.
XS =________________________
XXS =________________________
HRS =________________________
WI =____________________________
LCS =_________________________________
CI =____________________________
AL-STL =__________________________________
AL =_________________________________
HSS =_________________________________
TS =_________________________________
24. Write the size specification for an unequal leg angle including length. Use hypothetical sizes. Identify what each size represents.
25. a. What metric pipe size is approximately
equivalent to a U. S. Customary pipe size of %"? Refer to Appendix 4.
b. What does NPS % signify?
26. With reference to structural beam S, what do the following letters represent?
M =_______________________________________
S =________________________________________
W =_______________________________________
H =_______________________________________
HP =______________________________________
CRS
PLATFORM BRACKET HOLDER
ORDER NO. 1082 |
QTY 100 |
MATL. CRS PLATE
SPEC |
DATE: |
SCALE 1/2" = 1"
DRAWN BY: L. GRADY
DRAWING NO. 111276 |TOLERANCE ~5
COMPANY NAME
Refer to the drawing, Platform Bracket Holder, page 72.
© ® ® |
1. a. Give the dimensions for distances through (K.
® ----------------------
d _____________
<C ___________
®-----------------------
a------------------------
©-----------------------
b. If dimension was shown, what kind of a dimension would it be identified as?
2. a. What is the angle of the chamfer on the corners of the upright plates?
b. What is the angle tolerance?
Bill of Materials
|
7. What corner in the side view represents line N
8. How many holes are there in the completed part, not counting the pipe hole?
9. What size are these holes and how are they made?
10. What are the overall dimensions for parts ©
, and? List thickness, width, and length of each part.
@ ------------------------------------------------------------
d ___________________________________
3. What kind of plate is used?
b. What is the actual size of the outside diameter?
(Refer to the tables in Appendix 3.)
5. What line in the top view represents surface?
12. Which surface is specified to have a machine finish?
13. What fractional tolerance is specified?
))))))))))))))))))))))))))))))))))))))) 14. What angular tolerance is specified? 6. a. How many pieces of material are required )))))))))))))))))))))))))))))))
for fabrication of the part?
15. What line in the iront view represents corner W?
b. Prepare a bill of materials for the fabrication 16. What type of drawing is used? of the number required for completion of the order. ))))))))))))))))))))))))))
Refer to the drawing, Landing Bracket, page 74.
1. What size and type of material is used for all 11. What is the term applied to that part of the
pieces? structural metal shape indicated by line ©
12. Determine what angle is represented by ® (Use a protractor to determine this answer.)
2. What scale sizes are used on this print?
13. Considering the scale size used (excluding detail drawing) indicate the distances
3. At what angle is line ® to the vertical leg? reprinting the folWing dim^ton*
21"_________________________________
4. What line in the top view represents corner
? 30" _
36" _
5. What line in the top view represents corner
? 6'6"_
7'3"_
6. What line in the top view represents surface 14. Insert the missing reference dimension on the
drawing. (Examine the views to determine where the reference------------------------------------------------------------------------ dimension--- is required.)
8. What sizes are these holes? |
7. How many holes are there in the part?
15. a. Identify the location dimensions for the 0 .750 hole:
9. What are the dimensions of distances ® through © ?
<8 ---------------------------------------------------------
d _________________________________
<C ________________________________
®--------------------------------------------------------
a------------------------------------------------------------
10. What is the largest dimension shown on the drawing?
b. 0 .500 hole:
16. What is the overall length of the Z steel required to fabricate the bracket? Assume part ® is 56" long and allow 1/8" for each cut to be made from a single piece of angle.
17. How many brackets are required?
Refer to the drawing, Pump Base, page 76
1. List the types of lines found on the print.
10. What line in the front view represents surface ^ ?
2. List an item on the print that is considered to be a specification.
3. a. What size holes are required?
b. How many holes are required?
4. What are the location dimensions for the holes?
5. Identify a dimension that would be classified as a reference dimension.
6. What is the angle represented by the oblique (slanted) lines?
12. Make a complete list of materials required for the fabrication of the part.
Bill of Materials
|
13. The squareness of a rectangular part can be checked by measuring the diagonal distance of the corners. What is the distance from corner (S to corner ^ and from corner © to corner?
7. What type of joint is shown by the angular lines?
8. What are the dimensions for distances through?
14. What is the range of sizes for the 11" dimension? Max. ))))))))))))))))))))))))))))))))))) Min. )))))))))))))))))))))))))))))))))))
© ■© Q) |
© © © |
15. What is dimension ^ ?
16. How many pieces are required to make the pump base?
17. What is the total length of Z material required?
9. What line in the top view represents surface
(B ?
78 ■ Blueprint Reading for Welders |
Refer to the drawing, Skid Type Engine Base, page 78.
1. What scale size is used on the print? 12. What is the web size of the S-beam?
2. List the structural shapes needed to make the 13. Give the weight specification applied to &e
object. S-beam. Give a reason for including this
specification and interpret its significance.
3. Give the dimensions for the distances ® through.
14. List any dimensions not shown that could be used to specify the size of the channel.
© © |
(A --------------------
d ____________
<C ___________
(g ---------------------
d -------------------------
4. What is the distance from the center of hole (j to line (L?
5. What is the distance from point ® to point ®
6. What line in the side view represents surface ®
15. What is the channel flange width dimension? (Refer to the appropriate table in Appendix 2.)
16. Write the size specifications for the channel pieces according to an accepted form.
17. a. How many holes are required?
b. Describe the holes required.
c. Give the location dimensions for the largest hole.
7. What line in the side view represents the underside of surface (S?
8. What line in the side view represents point |
18. Make a complete list of materials needed to fabricate the unit, including overall sizes. Allow + for cutting and finishing on overall dimensions.
9. What type and size of material is used for parts (g and (V?
10. What is the flange dimension for the S-beam?
Bill of Materials
|