Query on Poly Carbonate (PC) - Durability of the Product

[Miner]

Yes, Small area only affected.

I have dismantled the product and verified. It looks like smoke formation inside the lamp.
While wiping by hand it sticking on the hand. But not in black color. It was in light grey.

Can we suspect with the electrical devices(Bulbs, Leveling device) inside the lamp.

If this small area is in close proximity to the bulb, it is highly likely that the heat generated by the bulb is either directly causing the issue or is accelerating another cause.

Is this a new issue on a new design? New issue on a existing design? or recurring issue on an existing design?

 

[vivkrish]

If this small area is in close proximity to the bulb, it is highly likely that the heat generated by the bulb is either directly causing the issue or is accelerating another cause.

Is this a new issue on a new design? New issue on a existing design? or recurring issue on an existing design?

Hello,

Yes Obviously Its near to bulb. But bulb covered with projection unit. So there is no direct contact of light from bulb to lens. This is the new issue in the existing design.

As I said earlier, It seems like small particles fallen on the lens surface. While wiping by hand it cleans.

Thanks,
Vivkrish.

 

[vivkrish]

Hi,

Your molded part may have mold in stress wherein if it is subjected to thermal stress such as heat for bulb and heat form the sun it becomes blurry on some areas.
We always do annealing at Tg temperature of the plastic if we found out our parts have extreme mold in stress.

Hello Kuyakut,

This is annealed part only. We also doing for all parts for stress release.

 

[Miner]

Yes Obviously Its near to bulb.

Please check your attitude. I am trying to help, and you never specified the location. It is always dangerous to make assumptions when trying to assist others in an unknown area.

But bulb covered with projection unit. So there is no direct contact of light from bulb to lens.

Direct contact is not necessary. The radiant heat is enough.

This is the new issue in the existing design.

Start looking for changes in the process whether at your location or at a supplier location.

As I said earlier, It seems like small particles fallen on the lens surface. While wiping by hand it cleans.

Have changes occurred in the projection unit covering the bulb that could allow the material of the unit or a coating to gas off and deposit on the lens?

Again, we are trying to help. You are trying to describe color to a blind person and getting upset when the blind person asks for clarification.

 

[vivkrish]

Please check your attitude. I am trying to help, and you never specified the location. It is always dangerous to make assumptions when trying to assist others in an unknown area.



Direct contact is not necessary. The radiant heat is enough.



Start looking for changes in the process whether at your location or at a supplier location.

Have changes occurred in the projection unit covering the bulb that could allow the material of the unit or a coating to gas off and deposit on the lens?

Again, we are trying to help. You are trying to describe color to a blind person and getting upset when the blind person asks for clarification.

Hello Miner,

Im very sorry. I Have verified my process there is no deviation. Im suspecting the outer coating of the bulb or reflector may evaporate and deposit over the lens surface. Because no other possibility. Ref the real image for better understanding. And suggest me.


Meet Google Drive – One place for all your files

Thanks,
Vivkrish.

 

[Miner]

My company firewall blocks access to external file sharing sites, so I cannot access the image. Have you tried attaching it to your post?

I agree that coating vaporization and deposition on the lens is most likely.

 

[vivkrish]

Pls ref the attachment

 

[Miner]

Judging from the location, it does appear that the heat of the light may be causing something in proximity to out-gas and deposit on the lens. The mark is also above the light which would be consistent with hot gases rising.

 

[vivkrish]

Judging from the location, it does appear that the heat of the light may be causing something in proximity to out-gas and deposit on the lens. The mark is also above the light which would be consistent with hot gases rising.

Hello Miner,

I have visited today a research body regarding the above issue. They suggested the dust particles which we have noticed, has may come from the aluminum die casing(ALDC 12) product which we are using inside the lamp(As a projection unit holder), also possibility of steel(SGCC) product also using inside the lamp(Heat absorbing purpose).

They told we can compare the elemental analysis for aluminium alloy material, SGCC and the dust particles which deposited on the lens. Then we conclude.

Then I have verified, the abnormal dust color matches the color of aluminium.

Since aluminium has high heat stability, I want to know Whether the aluminium alloy can Evaporate in bulb heat?

Or How can the dust particles came from the aluminium alloy.


Thanks,
Vivkrish.

 

[Miner]

You have reached the limits of my ability to assist. If I were in your position, I would pursue the elemental analysis to confirm that it is aluminum. ALDC 12 is an alloy, so it is possible that one of the alloying elements is responsible. You might also investigate the die release agent.