×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Die Cast vs. Steel Couplings and connectors

Die Cast vs. Steel Couplings and connectors

Die Cast vs. Steel Couplings and connectors

(OP)
I want to change some of our "Standard Work Practices". I want to ban all die cast fittings and use only steel.  Can the argument be made that the steel fittings are better, and if so, how? I know they cost more, but if I can get better bonding results then I'm OK with that.

RE: Die Cast vs. Steel Couplings and connectors

With both types there is a large range in the quality.  Assuming that they are both quality products, the only real difference is that the die cast will not take as much abuse (the fitting breaks) and it will fail earlier under fire conditions.  I'm not sure that the last one makes any real difference because if the fire is hot enough to melt the fitting the insulation has already melted.
Don

RE: Die Cast vs. Steel Couplings and connectors

(OP)
resqcapt19 - Thanks.  Those are really the only things I could come up with, also - durability.  What is your opinion of set screw vs. compression? Mine is that although I think set screw probably makes about as good a bond as compression and is a faster install, I prefer compression for the professional look it gives a facility.  Thanks again....        Jimi

RE: Die Cast vs. Steel Couplings and connectors

Set screw and compression fittings are both covered by ANSI and UL standards.  Both will perform to minimum standards In my experience set screw connectors go in faster (especially if the crews are using cordless drills with nut drivers).  
I have read and in my experience that set screw connectors are stronger.  There is an artical somewhere on the Loma Pietra earthquake that finds set screw connectors held up better.
HAve you read NECA standard NECA-1-2000?  It's a good place to start.

RE: Die Cast vs. Steel Couplings and connectors

Jimi,
   I agree that the compression type make a better looking job, but I think that the set screw do just as good if not better job for the connection.  For the best looking job you can use the indeter type, but I don't like them as far as meking a secure connection to the raceway. Here is a link to info on the interter type of EMT connectors.
http://www.hubbellonline.com/wiring/raco_bell/pdf/b8.pdf
Don

RE: Die Cast vs. Steel Couplings and connectors

I agree with what was said.
Although I saw a new type of fitting at a project the other day.  It was made up of die cast set screw fittings with electrical tape on either side of the fitting :)
Of course they were trying to suck a pull string through the conduit and had too much leakage at the fittings.  10 years later, they never removed the tape so it looked dumb.

RE: Die Cast vs. Steel Couplings and connectors

Steel is stronger.
Some cheaper grades of Die cast have so little screw travel that if the joint is stressed to the point that the connector stretches slightly the screw can no longer be tightened. (The screw head hits the side of the connector before the end of the screw applies pressure to the tubing.
Bonding issues;
The Canadian code banned the indent type of connector decades ago because of chronic loss of ground integrity.
While still accepted by code, you may have bonding issues with stretched die cast connectors.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources