Threaded Inserts - Standard Thread or Acme Thread?

  • Thread starter Thread starter Meesh Bono
  • Start date Start date
  • Tags Tags
    Standard Thread
Click For Summary

Discussion Overview

The discussion revolves around the selection of threaded inserts for a mechanical assembly, specifically debating the use of Acme threading versus standard threading. Participants explore the implications of thread types on force tolerance and material choices for the insert, considering both mechanical and practical aspects of the project.

Discussion Character

  • Technical explanation
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Meesh questions the necessity of Acme threading on the inside of the insert, suggesting that if the outside thread has a force limit, the inside thread's capacity may be irrelevant.
  • Some participants note that the inside thread's smaller diameter results in greater stress, which could impact performance.
  • There is a suggestion that Acme threading is preferred for lead screws due to specifications and low friction requirements, which standard threading may not meet.
  • One participant mentions the potential for binding and suggests using a material with lower friction, such as bronze, while another argues for consistency in material with the main parts.
  • Meesh expresses difficulty in sourcing the required threaded insert and seeks recommendations for manufacturers of Acme threaded inserts.
  • A suggestion is made that purchasing an Acme tap might be a cost-effective solution for creating the necessary threads.

Areas of Agreement / Disagreement

Participants express differing views on the necessity and implications of using Acme versus standard threading, as well as material choices for the insert. The discussion remains unresolved regarding the optimal threading and material selection.

Contextual Notes

Participants have not reached a consensus on the best approach to the threading issue, and there are unresolved questions about the force calculations and material properties that may affect the assembly's performance.

Who May Find This Useful

Engineers and students involved in mechanical design, particularly those working with threaded components and assemblies, may find this discussion relevant.

Meesh Bono
Messages
2
Reaction score
0
I have taken over a project halfway through (which is never an easy thing), and I need to get a threaded insert to place inside a steel piece that a threaded rod will move through. The original person working on the project wanted to get Acme threading on the inside of the insert and standard threading on the outside of the insert. The rod has Acme threading and is made from carbon steel.

I am wondering why the insert needs to have Acme threading on the inside though? The original guy thought it would be able to withstand more force, but if the outside thread is standard thread than does it really matter what the inside thread is? If the outside thread can only take so much force before it fails then it won't matter how much force the inside thread can take right?

Is there a force equation I can use to calculate when the threading will fail on the inside and outside of the insert? Maybe I can get a standard threading on both sides of the insert instead of trying to find a custom product.

Also, I've had another engineer tell me the insert should be made of bronze because he thinks the assembly will bind. But I thought the insert should be made from the same material as the main parts and the threaded rod (which is steel or carbon steel).

Any advice will help, I'm an electrical engineering student with a mechanical job!

Thank you!
Meesh
 
Engineering news on Phys.org
Meesh Bono said:
If the outside thread can only take so much force before it fails then it won't matter how much force the inside thread can take right?

The inside thread is of a smaller diameter so will have greater stress.

Presumably ACME thread is being used as it's a lead screw and standard thread won't meet the spec. Low friction is important for lead-screws hence your fellow engineers suggestion of selecting a material with lower friction.

If you can't find what you need need off the shelf you could have them made or redesign.
 
Uh ... from what I've seen of the Road Runner cartoons, I'd be real careful about those Acme products :D
 
  • Like
Likes   Reactions: billy_joule
billy_joule said:
The inside thread is of a smaller diameter so will have greater stress.

Presumably ACME thread is being used as it's a lead screw and standard thread won't meet the spec. Low friction is important for lead-screws hence your fellow engineers suggestion of selecting a material with lower friction.

If you can't find what you need need off the shelf you could have them made or redesign.

I've called many places looking for this part or someone that can make it, but no luck! If anyone knows of a company that makes ACME threaded inserts please share with me!
 

Similar threads

CNC: Deviations from the nominal thread profile due to tilting angle of the cutting insert?
  • · Replies 3 ·
Replies
3
Views
2K
Lubrication in fasteners and loss of preload
  • · Replies 18 ·
Replies
18
Views
3K
Forces applied on the bolts in the bike's hinge
  • · Replies 36 ·
2
Replies
36
Views
4K
Reusability of nuts and tapped holes + Choosing the right material
  • · Replies 3 ·
Replies
3
Views
2K
Need advice and hints for working with helium
  • · Replies 14 ·
Replies
14
Views
2K
Modelling a joint in a threaded rod, joint, nut and washer assembly
  • · Replies 1 ·
Replies
1
Views
2K
Inserting a steel rod into a current-carrying copper pipe
  • · Replies 7 ·
Replies
7
Views
2K
How to calculate how many threads I can use?
  • · Replies 6 ·
Replies
6
Views
2K
Seal rotating parts/reduce friction (hand-tight thread)
  • · Replies 9 ·
Replies
9
Views
3K
How much should I adjust torque when using anti-seize?
  • · Replies 22 ·
Replies
22
Views
7K