Investigating Contact Stress in HighSpeed Pipe Rolling

In summary, MrReliability's High Spin system is putting excessive stress on his tires. He is considering changing out the tires to something with a higher load rating.
  • #1
MrReliability
1
0
Contact Stress?

I have a "High Spin" rolling system that spins pipe to compact cement lining. We are using tandem 7-14.5LT D/8 bias-ply tires on each end of the axles with the pipe riding in the saddle between two sets of tires. The tires are running approx. 70 MPH for just over a min. The maximum weight of the pipe is 3500 lb. and it is held down with two sets of metal rollers that straddle the pipe with approx. 800 lb of downward force on each set.
My problem is that we keep separating the tread from the tire.

The combined weight on 8 tires, 4 sets of tandems, is as high as 5100 lbs. The diameter of the pipe range from 6" to 30" with weights of 30" pipe being around 5100 lbs and 6" pipe being around 2000 lbs.

The side wall is intact it is just the tread chunking off, on inspection of blown tires you can feel that the tread has separated completely around the crown of the tire.
here are 4 axles with the two inside axles being drivers and the outside two are idlers. I agree that the load will not be the same for all of the tires. The pipe has a bell on it that is considerably larger, thicker and heavier. There seems to be no pattern to the chunking. I am thinking that the small footprint of the pipe and the contact stresses from the pipe spinning might be a factor. On one side of the tire there is a footprint and on the other side (45-65 degrees apart) there is another footprint, except for the outside tires. I thought that the idlers would either go more or less frequently because of this but that is not the case.

I am not sure how to calculate the contact stresses, to see if this might be the culprit, or the forces associated with the tangential acceleration.

Any help would be greatly appreciated.

I have attached a photo of the system for your viewing pleasure!
 

Attachments

  • DSCN0900a.JPG
    DSCN0900a.JPG
    77.8 KB · Views: 497
Engineering news on Phys.org
  • #2
Welcome to PF, MrReliability.
I can't help with calculations, but I'm curious as to whether or not you've tried other types of tires, such as glass-belted radials. If so, were the results the same? Also, have you tried it with different inflation pressures?
 
  • #3
Hi MrR'.
When determining the normal force on the tires, did you consider the fact the verticle load isn't normal to the tire face? From the picture, it looks as if the pipe is about 30 degrees above verticle which means the normal load is twice the verticle load. If the downward (verticle) load is 5100 pounds, you need to double that for the 30 degree angle. (ie: normal load on tire = verticle load / sin(angle) )

It's this normal load that you have to compare to the tire's rating, not the verticle load. So what load are the tires rated for?

If the calculated load is still below the tire's rating, then it may be the radius the pipe makes on the tire that is causing an issue. Tires with a higher rating may help as Danger eludes to.
 
  • #4
Indeed. It would appear that you have a pretty substantial shear force on each tire which would seem to be the real culprit.
 
  • #5
As mentioned before, it seems quite possible that your are exceeding the maximum load rating of the tires. Also, you might check to see how hot the tires are getting, as a tire that is spinning at 70mph but doesn't have 70mph wind blowing over it may be getting far hotter than intended...
 

1. What is the purpose of investigating contact stress in high-speed pipe rolling?

The purpose of investigating contact stress in high-speed pipe rolling is to better understand the mechanical properties of the materials involved in the process and to determine the factors that contribute to contact stress. This information can then be used to optimize the pipe rolling process and reduce the risk of failure or damage.

2. How is contact stress measured in high-speed pipe rolling?

Contact stress in high-speed pipe rolling is typically measured using strain gauges or load cells that are attached to the rolling equipment. These devices measure the force and strain on the materials during the rolling process, which can then be used to calculate the contact stress.

3. What are the main factors that contribute to contact stress in high-speed pipe rolling?

The main factors that contribute to contact stress in high-speed pipe rolling include the material properties of the pipe and the rolls, the speed and pressure of the rolling process, and the surface roughness of the rolls. Other factors such as temperature and lubrication can also affect contact stress.

4. What are the potential consequences of high contact stress in pipe rolling?

High contact stress in pipe rolling can lead to material failure, such as cracks or fractures, which can compromise the integrity of the pipe. This can result in costly repairs or replacements, as well as potential safety hazards if the pipes are used for transporting hazardous materials.

5. How can the findings from investigating contact stress in high-speed pipe rolling be applied in real-world applications?

The findings from investigating contact stress in high-speed pipe rolling can be used to improve the design and manufacturing processes of pipes and rolling equipment. This can lead to more efficient and reliable production of pipes, reducing the risk of failure and increasing overall product quality. Additionally, the knowledge gained from these investigations can also be applied to other industrial rolling processes that involve high contact stresses.

Similar threads

Torque required to rotate steel pipe on rollers
    • Mechanical Engineering
Replies
4
Views
8K
Torque created around offset wheel
    • Mechanical Engineering
Replies
8
Views
1K
Automotive Inertia effects of components on a car vs mass fixed in car
    • Mechanical Engineering
Replies
6
Views
2K
Torque specs for 6,000lb party bike
    • Mechanical Engineering
Replies
7
Views
2K
Automotive Small block Chev (classic) exhaust notes/tuning physics etc
    • Mechanical Engineering
2
Replies
48
Views
21K
I A perfectly stiff wheel cannot roll on a stiff floor?
    • Classical Physics
4
Replies
116
Views
10K
Race Car Physics: Mastering Tire Contact Patch for Auto Racing Success
    • Mechanics
Replies
3
Views
10K
Surface roughness in 2D sinusoidal corrugation
    • Mechanical Engineering
Replies
1
Views
3K
Ground force applied to wheel in pure rolling motion at contact point
    • Introductory Physics Homework Help
Replies
1
Views
4K
Exhaust and engine accoustics for asthetics and performance
    • General Engineering
Replies
2
Views
6K

Hot Threads

Recent Insights

Back
Top