I think you meant that your cure temperature is defined by your Tg and HDT?
The problem highlights issues that can arise when publishing generalized data on a highly focused subject such as ultimate cure and there is not enough consideration for the possible deleterious effects.
We performed...
All things equal with a BPO/DMA cured vinyl ester laminate (.150" thick)60" diameter cylinder with a HDT of 220F:
1. Speed of reaction and ultimate exotherm produced will effect degree of initial cure but also can induce MORE stress into the laminate than a slower cure due to higher shrinkage...
CM you are correct. Normal operating pressure is 30-35 psi. However, the process is identical in all units built with slight variations of course due to the nature of the material. Over a broad range of units built we ONLY see this in sodium hypochlorite service. My guess is SCC.... we are...
If the carbon steel tank is in service you have a couple of considerations if your looking for long service life at that both hot and cold temps.
Need to know more about the temperature swings and normal operating temp but Derakane 8084 formulated in a glass flake coating will offer a very...
Demon,
I agree with your theory that the skin is breached but the solution seems to be in preventing the breach. What are your thoughts on exotherm induced stress into the laminate? The typical exotherm is around 120 - 140F @ .200".
If we can determine the cause of the cracks then can...
We have an ongoing issue with cracking around nozzle attachments in over the road filament wound tankers. Only see this in sodium hypochlorite service. Appears to be predominate in the high stress areas such as nozzles and to some extent head attachment.
1. Road tankers have very high dynamic...
Basalt comes from Russia because they have the basalt mines. You can get the material locally. They carry both epoxy and vinyl ester compatible.
Aliene Elkins
Advanced Materials Group
The ET Horn Company
www.ethorn.com
Why not consider combining carbon and E-glass fibers or Basalt fibers which are inexpensive and stronger than E-glass. Derakane 411 or 8084 which has highest elongation might fit the application.
Thinking out of the box here but might a cored laminate reduce the weight and provide the necessary...
Interesting observations. The laminate thickness is .170-.200". Would you say possible solution are:
1. Reduce the laminate thickness to say around .125" (Industy standard)
2. Control exotherm to reduce shrinkage?
Although we have this same laminate in HCL and many other services and don't...
We have an ongoing issue with cracking around nozzle attachments in over the road filament wound tankers. Only see this in sodium hypochlorite service. Appears to be predominate in the high stress areas such as nozzles and to some extent head attachment.
1. Road tankers have very high dynamic...
Hands down best material is Novolac Vinyl Ester such as Ashland Derakane 470-350 with 200 mil corrosion barrier, double carbon veil. 20% HCL good to 110C, up to 25% 100C, 30% 95C. Write a good specification and choose your fabricator carefully and will last for 25 years. Carbon veil is much more...
I have a design using ABAQUS 6.7 and need to find a new engineer continue the project. What do I need from the original designer? Do I just ask for the complete file and then it can be transferred to another designer?
Thanks,
George