Possible way to assemble two part 4

[apakshaypatel]

Hello Everyone,

I am designing a small sub-assembly consists of two parts. These two cylindrical parts OD= 1.75" and ID 1.25" are assembled using threading because it can be easily disassembled while doing maintenance. However, there is some constraint when this sub-assembly get together with other to become a whole assembly, due to which we cannot use thread. Is there is any way we can replace thread without adding any additional part?

I have attached a file for reference.
EDIT 1:
The Material is Delrin. I didn't want to complicate things that the reason I included optimal info which is not optimal I guess. Allow me to try to explain. Consider two parts Part A and Part B. Part A has two sub-parts, part A1 and A2. Same with part B, two sub-parts Part B1 and Part B2.

Both parts are under working at 50 ft from the surface of the machine. Part A reciprocate inside a pipe and Part B is stationary. During maintenance which would once in a year, part A1 and Part A2 should be able to disassemble and get it clean also Part B1 and B2 should be able to disassemble and get it clean.

Now, in order to do maintenance of both parts which is under a working condition at 50-60 ft from machine surface, We need to pull out both part A and B together by attaching them together consider part A is already attached with a number of SS rod which makes 60ft altogether.So from a surface, I need to get part A and Part B attached and pull out everything to surface, and after completion of maintenance place part B at its respective position and detach part A from the surface so that it can reciprocate and Part B will be stationary.

The part should be able to seal against water. we are not dealing with a heavy load, so you can ignore ay load constraint.


Thanks in advance
Akshay

 

[MikeHalloran]

1. Make it reliable enough to never need maintenance.
2. Press fit, or snap fit if plastic. You will need to modify the design to provide prying features and possibly a tool for disassembly.
3 Bayonet joint, which requires limited rotation, but can be implemented with no new parts.

If you want better answers, ask a better question, specifically including a lot more information about the parts, e.g.:
- materials
- service loads that the joint has to withstand
- frequency of disassembly and expected lifetime
- how well the joint has to seal against which liquids or gases
- operating temperature range

... and probably a lot more, basically whatever you can reveal without disclosing whatever your secret sauce might be.





Mike Halloran
Pembroke Pines, FL, USA

 

[drawoh]

apakshaypatel,

What is the constraint?

--
JHG

 

[apakshaypatel]

The Material is Delrin. I didn't want to complicate things that the reason I included optimal info which is not optimal I guess. Allow me to try to explain. Consider two parts Part A and Part B. Part A has two sub-parts, part A1 and A2. Same with part B, two sub-parts Part B1 and Part B2.

Both parts are under working at 50 ft from the surface of the machine. Part A reciprocate inside a pipe and Part B is stationary. During maintenance which would once in a year, part A1 and Part A2 should be able to disassemble and get it clean also Part B1 and B2 should be able to disassemble and get it clean.

Now, in order to do maintenance of both parts which is under a working condition at 50-60 ft from machine surface, We need to pull out both part A and B together by attaching them together consider part A is already attached with a number of SS rod which makes 60ft altogether.So from a surface, I need to get part A and Part B attached and pull out everything to surface, and after completion of maintenance place part B at its respective position and detach part A from the surface so that it can reciprocate and Part B will be stationary.

The part should be able to seal against water. we are not dealing with a heavy load, so you can ignore ay load constraint.

 

[MikeHalloran]

When you don't complicate things enough for us to understand what your actual problem is, we spend time trying to solve the wrong problem. We give away our time here for free, but that does not mean that our time is worth nothing. When you waste a valuable resource that is provided you gratis, you greatly insult the giver.



Mike Halloran
Pembroke Pines, FL, USA

 

[btrueblood]

Most of whom don't bother to read past Mike's last post. Frankly, I stopped reading when the description (Parts A and B and subparts blah blah) made no sense to the attached sketch (which shows part 1 and 2).

 

[apakshaypatel]

I really appreciate your timing and input. I would have tried much better way. ANyways, lesson learned. Mike, thank you for taking time. I will work something out. If you guys feel this waste of your time, please don't waste it anymore. I will figure it out something.

Thanks

 

[DAVIDSTECKER]

I'll take a stab at it.
From your drawing I assume that I am seeing a thread at the top where the SS rod attaches.
Also assume that "A" and "B" are basically hollow.
"A" and "B" are installed opposing each other with the part 2's facing each other.
It also sounds like there is some sort of seal or "O"-ring in the cylinder.
Is it possible to create a vacuum between A and B?
Can you replace the top stud with a quick disconnect hydraulic fitting that has the plunger sealing feature?
Since you probably can not lift the whole 50 Ft of rod out in one piece, add a "Tee" pipe fitting at the bottom end to thread the other half of the QD and at the side inlet run a vacuum line of flexible hose so you do not need to break the line when you remove sections of the lifting rod.
Look for a QD fitting that you can pull back the sleeve and it will snap in to place when the male half is engaged.

 

[DAVIDSTECKER]

I hope the link works.
This is sort of what I had in mind for the QD fitting