×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

(ASK) QTC and ER in API 6A 21st Edition

(ASK) QTC and ER in API 6A 21st Edition

(ASK) QTC and ER in API 6A 21st Edition

(OP)
Hello all,

May someone help me to explain in very simple definition, what is the different between QTC (Qualification Test Coupon) and ER (Equivalent Round).

I already read API 6A 21st Edition section 6.4 , but i still didn't get how to distinguish definition both of them.

Maybe to make it simple, i give an example if we want to produce Choke Valve 2", then which one of Choke Valve parts need to be QTC and ER ?

RE: (ASK) QTC and ER in API 6A 21st Edition

Hello Rizkyffq,

The ER is an estimate of the size of round bar with similar heat treating characteristics to the heat treated product. ER is a dimension in inches or millimeters; it is not a physical part.

The QTC is the physical part that gets tested to qualify the heat treated parts. The QTC must meet the ER size requirements.

For the choke valve example, you must test at least one QTC per heat. The QTC size must be such that has an ER equal to or greater than the parts, subject to the limitations and rules in API 6A 24th Edition 6.4. These rules are complicated for some cases, but can also be easily met for other cases. For example, if the choke body is a forging for PSL1 or PSL2 and batch heat treatment is performed (not continuous), either a 2.5" (or larger) round bar, a 2" x 2" (or larger) square bar, or a sacrificial forging body could be used as the QTC.

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! Already a Member? Login


Resources

Low-Volume Rapid Injection Molding With 3D Printed Molds
Learn methods and guidelines for using stereolithography (SLA) 3D printed molds in the injection molding process to lower costs and lead time. Discover how this hybrid manufacturing process enables on-demand mold fabrication to quickly produce small batches of thermoplastic parts. Download Now
Design for Additive Manufacturing (DfAM)
Examine how the principles of DfAM upend many of the long-standing rules around manufacturability - allowing engineers and designers to place a part’s function at the center of their design considerations. Download Now
Taking Control of Engineering Documents
This ebook covers tips for creating and managing workflows, security best practices and protection of intellectual property, Cloud vs. on-premise software solutions, CAD file management, compliance, and more. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close