Marsh Posted November 9, 2015 Report Share Posted November 9, 2015 Looking at it again - it now reminds me Merkava 3BdD and Merk 4 turret sides armor. Yes, but which generation? I am well out of the loop nowadays, but I know of at least four generations of armour modules that I have climbed over. Remember, with fully modular armour arrays on the Merkava, they are changed at much more frequent intervals than most other modern MBTs. Given the IDF's somewhat limited resources, the modules are changed in small batches, but the technology of the modules is cutting edge; ahead of most to be honest. Quote Link to comment Share on other sites More sharing options...
Walter_Sobchak Posted November 9, 2015 Report Share Posted November 9, 2015 I suspect that NERA is used in those "composite" modules http://otvaga2004.mybb.ru/viewtopic.php?id=1234&p=5#p631978 I wish I knew more about the armor modules on the Super 60. I asked my Dad about it once since he worked at Teledyne in that period. All he said was that the armor was done by a subcontractor and he didn't know any specifics about it. This makes sense since Teledyne Continental was an engine company, not an armor maker. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted November 22, 2015 Author Report Share Posted November 22, 2015 Potential Applications of Titanium Alloys in Armor Systems Apparently the M1A2's armor has some titanium alloy components. LoooSeR 1 Quote Link to comment Share on other sites More sharing options...
Militarysta Posted April 17, 2016 Report Share Posted April 17, 2016 Generally in older NERA armour packed "the main defender" is moving thiner back plate in eacht one NERA packed - in case T-72B it is those 3mm thick steel plate. During hit energy is transfering by rubber layer form front plate (21mm thick) to those 3mm thin metal plate. Ant this plate bulging and move is disturbing SC jet or bent "long rod". In mucht modern NxRA system the armour packed layout is diffrent - ussaly two thin (3-8mm) plates and thicker interlayer whit some "energetic" material. In sucht armour BOTH thin metal plates are moving - first backplate and as second - prontplate. So tehre is 2x more "moving and bulging plates" then in older NERA armour. Older one's type exmaple: T-72B (Ob.184) armour: https://zapodaj.net/images/386cbcc588bf1.bmp T-55 Haji armour (on T-55 ENIGMA) https://zapodaj.net/images/5f06c3f7eadd7.png And mucht more modern solution on Merkawa Mk.3D Dor Dalet - typical NxRA (both metal layer are moving): https://zapodaj.net/images/6cda17836100e.jpg EDIT - why I can't ad some photos? o.O EDIT2 - hosting on imigur help a lot Belesarius 1 Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted April 17, 2016 Author Report Share Posted April 17, 2016 Click the "image" button and post the image URL in the text box that comes up. Sometimes it works better if the images are re-uploaded to imgur. For some reason our forum has issues sometimes with images hosted on servers outside the USA. Quote Link to comment Share on other sites More sharing options...
Militarysta Posted April 17, 2016 Report Share Posted April 17, 2016 I had tried I have this error: https://zapodaj.net/4d96c1d2e48ed.jpg.html to many pictures posted today in my posts? or just polish serwers and google ones are not welcome? Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted April 17, 2016 Author Report Share Posted April 17, 2016 Weird. I can post all of those URLs as pictures, don't know why it's giving you problems. Try re-uploading the pictures to imgur.com, that usually works. Quote Link to comment Share on other sites More sharing options...
Militarysta Posted April 17, 2016 Report Share Posted April 17, 2016 OK, hosting on imigur solved porblems -thanks a lot! Collimatrix 1 Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 This has probably been asked and answered before, but what is the approximate density of a NERA array? I'm trying to use the tank design excel that Sturgeon provided, and it improbably gives a density of 8.74g/cm Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted April 19, 2016 Report Share Posted April 19, 2016 This has probably been asked and answered before, but what is the approximate density of a NERA array? I'm trying to use the tank design excel that Sturgeon provided, and it improbably gives a density of 8.74g/cm I would split the difference between rubber and steel for a start, so about 4.5 g/cm^3 Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 That's what I thought as well. Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 Looking at militarysta's post, it seems like a better estimate for NERA is something like 24mm steel + 6mm rubber + 22mm air. This gives a density of something like 3.75g/cm^3 if we use a rubber density of 1.1g/cm^3. So the total armour box probably clocks in just under 4g/cm^3. Edit: the tank design spreadsheet is also very weird about NERA efficiency (0.44 vs KE and 0.34 vs HEAT). This means that, according to the calculator, you'd have to be a complete piker to actually use NERA for anything. Seeing as this is manifestly not the case, my guess is that the efficiencies quoted are bullshit. Do we have any idea as to the real values? Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted April 19, 2016 Author Report Share Posted April 19, 2016 Looking at militarysta's post, it seems like a better estimate for NERA is something like 24mm steel + 6mm rubber + 22mm air. This gives a density of something like 3.75g/cm^3 if we use a rubber density of 1.1g/cm^3. So the total armour box probably clocks in just under 4g/cm^3. Edit: the tank design spreadsheet is also very weird about NERA efficiency (0.44 vs KE and 0.34 vs HEAT). This means that, according to the calculator, you'd have to be a complete piker to actually use NERA for anything. Seeing as this is manifestly not the case, my guess is that the efficiencies quoted are bullshit. Do we have any idea as to the real values? That is bizarre. Even dividing by the density relative to steel it still sucks on a mass basis. Could the number be expressed as a reciprocal or something? Most armor arrays are better vs HEAT than KE. This site gives Burlington a mass efficiency of 3 vs shaped charges and 1.5 against KE. Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 That is bizarre. Even dividing by the density relative to steel it still sucks on a mass basis. Could the number be expressed as a reciprocal or something? Most armor arrays are better vs HEAT than KE. This site gives Burlington a mass efficiency of 3 vs shaped charges and 1.5 against KE. No, I checked out the values and the only thing better than plain old steel, according to the calculator, is triple-hardness steel. I think whoever made it either fucked something up or has a massive boner for the return of the King Tiger. I'll plug in the proper values manually (thanks btw!) and run on that basis. Edit: having gone through the lookup table a bit, my best guess is that the author hates NERA for some reason. Some representative values for comparison (KE/HEAT): 97% alumina (0.97/1.5) 5083 Aluminium (0.43/0.7) Chobham (0.71/1.17) DU (1.5/1.5) Konkat-5 (4.29/8.57) plexiglass (0.4/0.7) Steltextolite (0.41/0.7) plain rubber (0.1/0.34) Titanium-6Al-4V (0.86/0.61) water 0.15/0.45) So according to this thing it would be better to use anything, including raw rubber, than NERA in an armour array. Guess the tank designers of the world must be on crack. Quote Link to comment Share on other sites More sharing options...
Collimatrix Posted April 19, 2016 Author Report Share Posted April 19, 2016 If the only thing that's showing as better than RHA is triple hardness then those are probably thickness efficiency figures, not mass efficiency figures. They're still wrong, but that's at least part of what's going on. Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 I grabbed the values from the worksheet after making a new set for NERA and compared the results in terms of average effectiveness/density. Here are the results after sorting: air Konkat-5 Relickt NERA (new values) Plexiglass Fused silica Chobham Ceramics-alumina various flavours of alumina Steltexolite Water 85% alumina Aluminum 2519-T87 Triple hardness steel various flavours of steel, aluminium alloy or titanium alloy mild steel rubber WHA Depleted uranium lead NERA (original values) Edit: the author just has a hate-boner for NERA and DU, I think. Quote Link to comment Share on other sites More sharing options...
Sturgeon Posted April 19, 2016 Report Share Posted April 19, 2016 No values Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 If the only thing that's showing as better than RHA is triple hardness then those are probably thickness efficiency figures, not mass efficiency figures. They're still wrong, but that's at least part of what's going on. Ah, you are correct! The values are labelled TE (KE/HEAT)... Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 No values averaging it out and dividing by density just produces a relative scale, so no values are really needed unless you're looking for order-of-magnitude differences. In any case: Armor Type density (Ave TE/density) Air - 100 Konkat-5 4S22 ERA - 1.05 Relikt 4S23 ERA - 0.96 NERA-Rubber (new values) - 0.60 Plexiglass - 0.49 Fused Sicila - 0.45 Chobham - 0.42 Ceramics-Alumina - 0.41 AD-90 (90% Alumina) - 0.33 AD-97 (97% Alumina) - 0.33 AD-92 (92% Alumina) - 0.32 Steltexolite - 0.32 Water - 0.3 AD-85 (85% Alumina) - 0.27 Aluminum 2519-T87 (MIL-DTL-46192 (MR)) - 0.20 RHA - Triple Hardness - 0.20 Aluminum AL-7039 (MIL-DTL-46063H) - 0.19 RHA - Russian-hardened - 0.17 RHA - High Hardness - 0.17 Aluminum 5083 (MIL-A-46026) Perforated - 0.17 Titanium-6Al-4V (MIL-A-46077) - 0.16 Titanium-6Al-4V (MIL-A-46077) - 0.15 RHA - Semi-Hardened - 0.15 RHA - Thin - 0.14 Aluminum 5083 (MIL-A-46026) Honeycombed - 0.14 RHA - American - 0.14 RHA - Russian-welded (WW2) - 0.13 RHA-Rolled - 0.13 Aluminum 5083 (MIL-A-46026) - 0.12 RHA-Perforated - 0.12 RHA - Cast - 0.12 Mild Steel - 0.11 Rubber (Some kind) - 0.10 WHA (HM1100) - 0.08 WHA (90% W) - 0.08 Depleted Uranium - 0.08 Lead - 0.07 NERA-Rubber (original values) - 0.04 Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 In any case, I think we can all agree that if you cannot fill your tank with air, fill it with plexiglass or ERA blocks instead. Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 For the triple, here are the values scaled to RHA: Armor Type Average relative to RHA Air 785.00 Konkat-5 4S22 ERA 8.25 Relikt 4S23 ERA 7.53 NERA-Rubber (new values) 4.71 Plexiglass 3.85 Fused Sicila 3.56 Chobham 3.32 Ceramics-Alumina 3.18 AD-90 (90% Alumina) 2.62 AD-97 (97% Alumina) 2.55 AD-92 (92% Alumina) 2.49 Steltexolite 2.48 Water 2.36 AD-85 (85% Alumina) 2.12 Aluminum 2519-T87 (MIL-DTL-46192 (MR)) 1.59 RHA - Triple Hardness 1.56 Aluminum AL-7039 (MIL-DTL-46063H) 1.48 RHA - Russian-hardened 1.32 RHA - High Hardness 1.32 Aluminum 5083 (MIL-A-46026) Perforated 1.31 Titanium-6Al-4V (MIL-A-46077) 1.28 Titanium-6Al-4V (MIL-A-46077) Perforated 1.21 RHA - Semi-Hardened 1.17 RHA - Thin 1.12 Aluminum 5083 (MIL-A-46026) Honeycombed 1.12 RHA - American 1.10 RHA - Russian-welded (WW2) 1.02 RHA-Rolled 1.00 Aluminum 5083 (MIL-A-46026) 0.97 RHA-Perforated 0.92 RHA - Cast 0.91 Mild Steel 0.90 Rubber (Some kind) 0.75 WHA (HM1100) 0.66 WHA (90% W) 0.66 Depleted Uranium 0.63 Lead 0.52 NERA-Rubber (original values) 0.35 Quote Link to comment Share on other sites More sharing options...
Militarysta Posted April 19, 2016 Report Share Posted April 19, 2016 Edit: the tank design spreadsheet is also very weird about NERA efficiency (0.44 vs KE and 0.34 vs HEAT). This means that, according to the calculator, you'd have to be a complete piker to actually use NERA for anything. Seeing as this is manifestly not the case, my guess is that the efficiencies quoted are bullshit. Do we have any idea as to the real values? Yes, I have a some "hard data" :-) Polish very very primitive NERA for BRDM-2 upgrade, it was study project: Offcial statment after tests: W ramach sfinansowanego przez Ministerstwo Nauki i Szkolnictwa Wyższego pro-jektu rozwojowego nr 0019/T00/2008/06 zrealizowano w WITPiS program badań ekspe-rymentalnych z użyciem granatów PG-7M, o przebijalności stali RHA 300330 mm. Przeprowadzono badania modelowych rozwiązań ekranów prętowych (rys. 1) i kaset typu NERA. Uzyskano rezultaty, dla których nie następuje przebicie pancerza (...) Kasety typu NERA mogą być obecnie stosowane dla cięższych pojazdów lub tylko fragmentami dla lżejszych (np. tylko do ochrony przestrzeni załogowej). Ze względu na ich budowę gęstość powierzchniowa tych rozwiązań wynosiła w trakcie badań od 220 do 390 kg/m2. Skuteczność kaset NERA jest znacznie wyższa od skutecz-ności ochronnej ekranów prętowych. Porównując gęstości powierzchniowe opracowanych konstrukcji, uzyskano roz-wiązania o dużej efektywności masowej w stosunku do stali RHA. Przebijalność tej sta-li dla granatu PG-7M wynosi 300÷330 mm tj. 2340÷2570 kg/m2. Dla kaset typu NERA, licząc gęstość powierzchniową osłony razem z pancerzem kompozytowym i spall-linerem, można uzyskać ochronę o efektywności masowej ok. 4÷4,5. Zastosowane wy-kładziny wewnętrzne (spall-linery) skutecznie redukują kąt rozlotu odłamków, zmniej-szając tym samym poziom zagrożenia zranieniem dla większej liczby osób znajdują-cych się wewnątrz pojazdu. translate: As part financed by the Ministry of Science and Higher Education pro-development project No. 0019 / T00 / 2008/06 was carried out in WITPiS research program experimental with grenade PG-7M whit steel penetration - 300-330mm RHA. Conducted studies of model solutions screens pannels (Fig. 1) and the armour type NERA. The results obtained, for which there is no armor penetration (...) NERA cassette type can now be used for heavier vehicles or just for lighter fragments (eg. Only to protect the crew). Due to the construction of the density of the solution during the tests was between 220 and 390 kg / m2. The effectiveness of cassettes NERA is much higher than the effective-ness of the protective screens rod. Comparing the density of developed surface structures obtained spread-linked with high efficiency mass relative to the RHA steel. Penetration of fixed-li for the grenade PG-7M is 300 ÷ 330 mm, ie. 2340 ÷ 2570 kg / m2. For cartridge type NERA, counting the density of the surface cover with composite armor and Spallliner, you can get the protection of the effectiveness of mass approx. 4 ÷ 4.5. O-used interior of the veil (Spall-liners) effectively reduce the angle rozlotu debris, reduce-stirring the same level of risk of injury to more people-smokers are inside the vehicle. And second: NERA layout effectivnes for diffrent energetic material in "bulging plates": if You want I can post more resercht like this above. More or less - typicle SINGLE NERA layer vs typical (copper cone, RDX melt) SC warhed will give circa 22% penetration reduction. In case other then rubber material - wy have circa 27% reduction for rather NxRA material then pure NERA. Not very impressive? Vell, in modern tank we have a lot NERA layers: (my model of known M1A1HA side armour...) Sturgeon, LoooSeR, ApplesauceBandit and 2 others 5 Quote Link to comment Share on other sites More sharing options...
Toxn Posted April 19, 2016 Report Share Posted April 19, 2016 This is great! Please post more hard data, on any topic, if you have it. Quote Link to comment Share on other sites More sharing options...
Militarysta Posted April 19, 2016 Report Share Posted April 19, 2016 OK, as exmaples german NXRA and NERA tests and...NxRA armour on Leo-2A5/A6(famous "wedges" on Leo-2A5) btw: You can find those PFD by using title in google :-) Enjoy! Soviet ERA and German double NERA: ps. and check this: https://zapodaj.net/images/47b609390faa3.bmp and find pfd via google - agin - Enjoy, it very good pdf Collimatrix 1 Quote Link to comment Share on other sites More sharing options...
Bronezhilet Posted April 19, 2016 Report Share Posted April 19, 2016 This has probably been asked and answered before, but what is the approximate density of a NERA array? I'm trying to use the tank design excel that Sturgeon provided, and it improbably gives a density of 8.74g/cm His values for ERA are fucked as well. He has 6.12 g/cm³ for Kontakt-5. It's actually ~3.05 g/cm³. ...it looks like he just multiplied the weight of a single Kontakt-5 sandwich by two, because you know, 2 sandwiches per block. ...THAT'S NOT HOW THAT WORKS, THAT'S NOT HOW ANY OF THIS WORKS. Quote Link to comment Share on other sites More sharing options...
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