Blueprint/ Welding Symbols

Date 08-14-2003 18:02

Alison,
A great reference tool that you will need at your disposal for teaching is the "Standard Symbols for Welding, Brazing, and Nondestructive Examination" by AWS Publication A2.4-98. This book covers the definitions of the parts of the welding symbols and discusses the difference in the arrow side and opposite side.

As far as your question referring to the arrow, Here is what the AWS A2.4 has to say:
Paragraph 3.2.1 "Arrow side. Welds on the arrow side of the joint shall be specified by placing the weld symbol below the reference line."
Paragraph 3.2.2 "Other Side. Welds on the other side of the joint shall be specified by placing the weld symbol above the reference line."
Paragraph 1.5 "Placement of the Welding Symbol. The arrow of the welding symbol shall point to a line on the drawing which conclusively identifies the proposed joint. It is recommended that the arrow point to a solid line(object line, visible line); however, the arrow may point to a dashed line(invisible, hidden line)."

As far as I know there is no reference to whether the arrow points up or down, merely that it points to a joint to be welded. I was a Structural Steel Detailer for several years before I got into NDT and Inspection and I have pointed to joints from above the joint pointing down, and below the joint pointing up, and it doesn't change the meaning of the symbol as for what side gets welded. Arrow side and other side, rule as for what side of the joint gets welded.

This book will be your best freind in trying to communicate welding symbols to your students, I highly recommend that you get a copy for your classroom.

Now that I am Inspecting and involved with the welders more, I see lots of welding symbol mistakes on the shop drawings. I know what the detailer has in mind, because I was a detailer, but the symbol he/she may have used is incorrect for the type of joint.

I was re-reading your post and you said you were confused about the arrow use vs the reference line use. I'll take a stab at trying to clarify.

The reference line is related to the joint via the arrow. They are seperate entities, but are the parts of one weld symbol. The arrow points to the joint that the information on the reference line applies to. For example...If I point to a joint that needs a 1/4" fillet weld, welded with SMAW on the near side....I would draw an arrow pointing to the joint with the reference line attached to the arrow, and add a 1/4" fillet weld symbol below the reference line and I may put a tail on the reference line with a welding process(SMAW) indicating that the Shielded Metal Arc Weld welding process is what I want the welder to use to weld the joint. The tail is for additional notes or info to help the welder know what you are trying to convey.
Let me know if I muddied up the water or helped to clear it up,
John Wright

By UCSB

Date 08-14-2003 18:30

John makes a good point, but I would like to add that the arrow is also indicative of which side of the joint receives preparation. The arrow should point to the side of the joint that will receive the bevel, J-groove or flange. If the arrow is broken then the other side should receive the preparation.

Roger King

By jwright650 (*****)

Date 08-14-2003 18:39

Hi Roger,
You're right and make a good point about the arrow. I was afraid to get too technical until I had a feel whether or not all this was being understood. In my ramblings, I wonder if people can follow me sometimes. :)
John Wright

By Alison

Date 08-14-2003 18:45

Being a rambler myself, I speak ramblese well:)

By Alison

Date 08-14-2003 18:44

Thank you both...it all seems really quite logical (no muddying it up), and I plan to get the reference book..thanks for the recommendation. I understand the arrow vs. the reference line now...I've been getting my info from so many different sources it can be a little confusing.

I am going to introduce a VERY basic level of this to my pre-voc students. They are special needs with misc. needs, but including educational...this translating into they get overwhelmed very easily. What would you say are the most important/basic parts of the symbols to learn? There seems to be a bazzillion levels to the symbols. I understand as a professional it is all important to know, but I just want to give the kids an intro, so if/when they go on to some sort of vocational program (very likely with a few), they'll have a little symbol/blueprint reading knowledge under their belts.

By jwright650 (*****)

Date 08-14-2003 18:58

Alison,
I think after you receive your copy of A2.4, you will see that it is laid out to where you can be as simple or as complex as you need. I think you will be able to break down what AWS has already put together and meet the needs of your students. I would start with the basics as we have discussed already concerning the parts of the welding symbol and go from there to arrow side, other side. And you can get as complex as many reference lines in one weld symbol to show an array of tasks and in which order the welder/inspector is to complete them.
I'm glad you can read ramblese :)
John Wright

By ssbn727 (*****)

Date 08-14-2003 20:36

Hello UCSB!

Am I correct when you wrote in your reply that: "the arrow is indicative of which side of the joint recieves preparation. The arrow should point to the side of the joint that will receive the (edge preparation) bevel, "J"-groove, or flange. If the arrow is broken then the other side should recieve the preparation."

Unless the AWS changed things then, I have to respectfully disagree with you on the last sentence of your reply because, I checked again, and again, and I cannot find anything in any of the books that I have used repeatedly to teach with, up to the most current issues, that supports the last sentence. Please enlighten me on this if you would because, I personally always interpreted and believed that the reference line was the only component that determined where the weld would be deposited... A broken Arrow let's the weldor or anyone else versed in interpreting the welding symbol that, there is indeed a member that requires edge preparation and that the arrowhead will point to that specific member but, not to determine which side of the joint the weld is to be deposited... Again, if things have changed then, I would like to know why nobody informed me about this... Look foward to your reply.

Respectfully,

SSBN727 Run Silent... Run Deep!!!

Btw, Is anyone experiencing any power outages in their area because, I just heard about outages in New York, Detroit, Cleveland, Toledo, Toronto, Ottowa, etc. ??? I'm in Pittsburgh and every thing is fine out here... Let us know if you can, thanks.

By jwright650 (*****)

Date 08-14-2003 21:04

Hello SS,
In AWS A2.4 paragraph 3.4 states: "Break in Arrow. When only one joint member is to have a bevel, or J-groove, the arrow shall have a break and point toward that member (see figure 6). The arrow need not be broken if it is obvious which member is to have a bevel or J-groove. It shall not be broken if there is no preference as to which member is to have a bevel or J-groove."

The way I was seeing this statement, is if you prefer to have a single or double bevel joint, you need to break the arrow and point to the member that you want beveled and the other member will stay square, and the same for J-grooves.

AWS Disclaimer:
Any mispellings are all mine(John Wright) and AWS assumes no responsiblity for all the boo-boo's I may have in my postings. I know you guys are thinking that guy can't type a lick. :)
John Wright

By jwright650 (*****)

Date 08-14-2003 21:07

Hello again SS,
No power outages here, either.
John Wright

By ssbn727 (*****)

Date 08-14-2003 21:51

Hello JW!!!

Thanks for that clarification because, it does'nt state that the broken arrow will indicate that the other side of the joint from the arrowhead in other words, the opposite or "behind" side of the joint where the welding symbol's arrowhead is located, should recieve the preparation so, the statement can be misleading if this is not clearly described...

Anyway, I just thought that the last sentence part of the statement from UCSB needed clarification so, once again, thanks John!

Respectfully,

SSBN727 Run Silent... Run Deep!!!

Btw, you do'nt type that bad!!! Heck, everybody including myself makes typo's of one form or another!!! Keep giving us your best because, it's always GOOD!!!

By jwright650 (*****)

Date 08-14-2003 22:07

SS,
I'm not trying to put words in his mouth or anything, but I didn't really think he meant it the way it read. But I knew what he was saying or trying to say when I read it. That's why I try to quote it directly from the source, cuz, hard as I try, I always goof it up somehow. I think it's got something to do with that "ramblese" that I speak.
It did need clarifying, and if you had not pointed it out, I wouldn't have noticed. I read over it so fast, that I had already agreed with it. I re-read it and saw what you had picked up on....good eyes there SS!:)
John Wright

By ssbn727 (*****)

Date 08-14-2003 22:15

JW,
Thanks because, I thought this old fart was going blind or losing my mind!!! Thanks again JW!
No disrespect intended to UCSB either!!!

Now I can go and dive into the pool relaxed... See ya later alligator!!!

Respectfully,

SSBN727 Run Silent... Run Deep!!!

By insp76

Date 08-15-2003 02:33

John, just to give you another reference,from the book of all books, AWS Welding Inspection Technology Module 4 , Welding and Nondestructive Testing Symbols , Copyright 1986 pages 4-8 and 4-9. ....Most of the weld symbols appear much like the actual weld configuration, which makes it easier to remember exactly what type of weld is specified by a particular symbol. Another feature which should be noted for all of those weld symbols which represent welds having only one of the two members prepared is that the perpendicular side of the symbol will always appear on the left side (e.g.,bevel, j- and flare-bevel grooves;fillets;and corner -flange welds). For these groove welds,the designer can designate which of the two members actually receives the preperation by using an arrow with a break in the line. The convention is that the last segment of the arrow points to that member receiving the specified preperation....This publication seems to explain why there is a need for a broken arrow. Now what all this has to do with Galvanic Corrosion, I don`t have a clue, Have a good one!

By ssbn727 (*****)

Date 08-15-2003 05:08

Hey Insp76!

Neither do I but, heck - who cares!!! We're talking about SYMBOLS here... I'm glad you and others could add another reference to this discussion... Thanks everyone and the same goes to you Alison!!!

Good to hear from you too Insp76!!!

Respectfully,

SSBN727 Run Silent... Run Deep!!!

P.S. Alison, I have to apologize for all the fuss over your question so, please forgive me.. I just hope that by clarifying the interpretation of these symbols, you do'nt get more confused than you were initially!
My intention was to make sure you got a clear understanding of how the components of these symbols work with respect to all of the other components or elements that make up a variety of welding symbols and how they interelate to the joints in the prints or drawings...
I hope that we can encourage you and others to feel comfortable about getting the guidance you seek here or just to get an opinion or two or three or more about any welding related issues in this forum!!!
Keep up the great work that you're undoubtedly doing because, heaven knows, you've got a very tough, and very important job trying to convince those youngsters how rewarding and interesting this field is...
Thanks for your understanding, and I hope to read more from you and anyone else for that matter... SSBN727

By pipewelder_1999 (****)

Date 08-15-2003 03:38

To follow up John and other responses

Another source with a similar statement as A2.4 is Welding Handboo Volume 1 9th edition page 372. Under the heading "Orientation of Specific Weld Symbols".

Also there is an online reference at http://www.adtdl.army.mil/cgi-bin/atdl.dll/tc/9-237/Ch3.htm#fig3_19

Have a good night

Gerald Austin

By UCSB

Date 08-15-2003 14:47

SSBN-
John wrote it out better than I.
What I was trying to say is the broken arrow will point to the piece that gets the prep, while the symble will indicate which side of the piece to prep.
All I can think about is vacation next week, much less welding symbles. ;)

Hope you guys back east get your power back on soon.

Roger

Gerald- nice sketch

By MBlaha

Date 08-19-2003 11:17

I have been teaching welding for 5 years along with welding symbols classes and WPS classes. This is the first time I ever realized that a broken arrow pointed to a certain piece in a weld joint. Thanks for the infromation. I will definitley incorporate this into the last couple classes I teach.
Going on Vacation huh SSBN? cool where you off too? I will be going on vacation Oct 10th. Going back to building and repairing boilers :) which after sitting in a stuffy office the last 5 years will be a vacation every day. While I empathize with the people on the east coast, the lights going out could not have come at a better time for me. Hopefully our leaders will see how vulnurable we have become in our dependence on electricity and adress some of the issues here on the home front and make our people at home our priorities. (yea right LOL) Anyway, the demand for craftsman may rebound after this disaster. I sure hope so.

Mike

By pipewelder_1999 (****)

Date 08-14-2003 23:18

Hello Alison,

You have some great responses here. I prepared a brief sketch at http://www.weldinginspectionsvcs.com/arrowBreak.htm . That may help you or your students.

Have a nice day

Gerald Austin

By Alison

Date 08-28-2003 15:05

Thank you all so much! I appreciate that you all have discussions trying to figure out nuances...I don't feel so bad for being confused by it all. All the information and references have been VERY helpful. The friendliness has been appreciated too.

Hello to Pittsburgh from a former Pittsburgher! Love that town! Made me love steel.

Alison

By ssbn727 (*****)

Date 08-29-2003 21:50

Hey Alison!!!

We're watching the game tonite at the POOL!!!

The last one of the preseason!!!
I hope we WELD them to the ground so that they ca'nt MOVE!!!
The Defense better start Gouging their offense to smitherines!!!!!
Our wide recievers will be CUTTING their defenses to pieces for the scrap heep!!!!! I just hope that our STEEL CURTAIN does'nt fatigue or fail during the second half of the game!!! They've been showing signs of buckling lately so, I'm afraid that coach Cowhers better have some structural reinforcements for our STEEL CURTAIN!!! Maybe put in some TITANIUM instead??? Once a Pittsburgher, always a Pittsburgher!!!
Show them what we're made out of Alison!!!!!

GO STEELERS!!!!! GO STEELERS!!!!! GO STEELERS!!!!!
Here we go Steelers, Here we go!!!!!

Respectfully,

SSBN727 Run Silent... Run Deep!!!