Is it possible to use vacuum during filament winding to overcome the issue of porosity? If so, what is the most convenient method? Thanks.
why would you want to do this
If you are having issues with your winding, you need to figure out what is going wrong!!! Your tows might not be saturated enough, or too much bandwidth, etc. If you need to, do a standard wet lay-up bagging style. if the part is finished, add perf release film, and bleeder. .
Wright now I am doing project on Filament wound GRP pipes,
To predict mechanical properties of filament wound pipes I have few questions,
So please help me,
- To predict laminate thickness = mass(gram/meter^2) x 1/ρ x ratio volume contain
So if i am using 2400tex roving
1tex = 1gram/Km = _____gram/meter ^ 2
How to convert in gram/meter^2 ? ? ? ( theoretically )
- If normal winding I am doing than its ok
How to consider sand layer and other Mat in calculation
For effective Elastic Moduli calculation ? ? ?
- One layer of filament winding is like
In forward its +55 and reverse in -55 angle
Case 1: so separately its unidirectional value of β efficiency of fibers is 1 and thickness is divide in both +55 and -55 degree,
Case 2 : consider only +55 degree than its cross ply β = 0.5 and thickness would be full.
What would be consider ? ? ?
From a units standpoint it looks like you’re going to need the density of your fiber to to do the calculations you need.
I’m moving this to Engineering Talk due to the nature of the questions.
no not density
for laminate thickness prediction = mass(g/m^2) x 1/density x volume fraction
i need to convert g/meter to gram/m^2 for rovings in unit tex
I know, thats why I said you’re probably going to NEED density and from your formula it looks like I was right 
I’ve never done this calculation, or even heard of the units. If you get it figured out could you post the steps here?
ok i will
do u have any 6x6 stiffness matrix calculation ? ? ?
from macro layer properties i have but don t getting true values…
I know how to perform 6x6 matrix calculations for in plane properties. If you can post your composite properties I can make a Matlab script and post it here. Maybe there just a simple mistake somewhere? It happens to me all the time.
I don’t have much experience with filament winding, but I do have a bit of experience with interpreting equations.
The way I see it, if you break down your equation,
mass(gram/meter^2) x 1/ρ x ratio volume gives you laminate thickness.
Then, mass(gram/meter^2) x 1/ρ would give you only the carbon fiber’s contribution to the thickness of a laminate layer layer.
If you remove the density function, then you only get the mass(gram/meter^2) which would be contribution of only the carbon fiber’s to the thickness only knowing the weight (as density converts a weight to a volume).
So in summary, It seems to me that converting the g/m to g/m^2 would require the initial number of filaments per tow and processing data, like how much tension do you put on the tow when winding.
compute the laminate properties of [0/90/ +and - 30]s with thickness tk = 1.5 mm Ef=241Gpa, vf = 0.2, Em = 3.12GPa, vm =0.38x ,
fiber volume fraction = 0.6,
answers
E1=145880 G12= 4368 v12=v13=0.263
E2=13312 G23=4528 v23=0.470
and
Ex=78901 Gxy=17114 v xy=0.320
Ey=47604 Gyz=4475 v yz=0.364
Ez=16023 Gxz=4439 v xz=0.280
please send me Matlab codes if u have…
email me on hrds234@gmail.com
thank you…
Can you send me your calcs so I can look over them? Off the bat I see you have properties normal to the composite plane. This is something I have not done. I’ll work on what I know, which is properties in the fiber plane over the next week. Hopefully we get the same answers!
hey i don t knw this things thats why i am asking…
i wann to learn how to do it…
No worries,
I don’t know much either which is why I’m here all the time
I have a busy weekend so give me about a week to get it done.
Been working on this but I have a question. No shear modulus is given but it can be calculated using E/(2(1+nu)). Is this relationship valid for your material?
Here are the preliminary calcs for in plane stiffness of your laminate. I don’t know the units of your numbers but it looks like the first few digits are a close match!
I opted to use Mathcad so everyone can read the analysis and see what’s going on. Lemme know if you want me to continue and get teh rest of the numbers!