tag:blogger.com,1999:blog-5030145265861917845.post2244537756701048018..comments2024-03-20T11:41:56.776-04:00Comments on Tank Archives: Heavy Tank Production, Spring-Summer 1945Peterhttp://www.blogger.com/profile/09622237223229485503noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-5030145265861917845.post-31479098135905336702016-10-07T15:27:25.449-04:002016-10-07T15:27:25.449-04:00Welding armor seams does not work without flaws wi...Welding armor seams does not work without flaws with the technology of the time. Thick armor plates require the presence of chromium and nickel to be tough. Yet those alloying agents increase the sensitivity to temper britellness. Any welding, secondary heat treatment will have a portion of the two joined plates being in the ideal temperature zone for temper britellness. <br />Due to the characteristics of the austenitic weld seams it became necessary to design the structures in such a way that forces, particularly those resulting from combat action or operation, would not be absorbed exclusively through the weld seams. Rather, the structures were designed so that the sheet metals or components to be connected were mutually supported in such a manner that the forces did not flow only through the weld seams (e.g. by keyed plates). It was further necessary to design the structure of the weld seams in such a manner that direct firing on the weld seams was impossible. This was accomplished in that the weld seams were protected, if possible, by a cover of armor steel. Butt joints or similar connections of sheet metals made of armor steel must be avoided by any means since the region of the weld seam has a lower resistance to enemy fire than the unwelded sheet metal so that these points would constitute a particularly weak point of the structure.<br /><br />The IS3 pike nose is suffering because the welds are unprotected by armor plate and thus constitute a weak zone and the nose is the principal structural strength member and subject to many forces going through.critical masshttps://www.blogger.com/profile/02366274198749901618noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-47231299565827009232016-05-19T14:09:58.987-04:002016-05-19T14:09:58.987-04:00Pretty sure the only thing the IS-4 was rushed int...Pretty sure the only thing the IS-4 was rushed into was de facto exile in the Far Eastern military districts where its excessive weight caused fewer bridge-related problems...<br />And given the comparatively minuscule production numbers and cancellation already around '49 it certainly wasn't much of a replacement for anything. :/Kellomieshttps://www.blogger.com/profile/04915110653443066212noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-79731610330873721572016-05-19T10:30:17.213-04:002016-05-19T10:30:17.213-04:00Regarding IS-3 reliability, when prototype Kirovet...Regarding IS-3 reliability, when prototype Kirovets-1 was tested, the reliability was judged to be comparable to IS-2. Svirin states that IS-2 and other WW2 vehicles were also subjected to UKN programs to make them adequate during peace use. Priority was given to T-44, T-54 and IS-3 because they were going to form the backbone of the Soviet Army Tank Armies.<br /><br />Regarding the misterious ballistic test, Svirin quotes an Army officer named Gorlitskiy (*). He is quoted several times in his book (Steel fist of Stalin. History of Soviet tank 1943-1955), but he is not in the references.<br /><br />In any case, IS-3 was removed from production and IS-4 rushed to it.<br /><br />(*) He is also quoted when explaining UKN program.<br /><br />P.S I read your blog daily, I hope you carry on with this excellent work.Alejandrohttps://www.blogger.com/profile/05537203226584815118noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-47184035482085748962016-05-19T10:29:31.714-04:002016-05-19T10:29:31.714-04:00This comment has been removed by the author.Alejandrohttps://www.blogger.com/profile/05537203226584815118noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-92009547842928006622016-05-19T09:19:39.731-04:002016-05-19T09:19:39.731-04:00Yes, cast armour was easier to make complex shapes...Yes, cast armour was easier to make complex shapes with than welded, both the Soviets and Americans realized this early on. Unfortunately you can't get away from problems with thickness here either: the thicker the cast armour the higher the chance that there will be defects.Peterhttps://www.blogger.com/profile/09622237223229485503noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-29704147527990235702016-05-18T12:04:10.779-04:002016-05-18T12:04:10.779-04:00Speaking of welding though, I remember once runnin...Speaking of welding though, I remember once running across a discussion on the topic of joining armour plate of tanks by that method. IIRC someone who claimed to have professional experience with welding pointed out that very thick plates get increasingly difficult to properly weld together by hand, what with humans lacking the precise thermal sensors and split-second timing industrial robots boast. (We may recall here the persistent problems the Germans had with the seams of their heavier tanks.) I also recall seeing it mentioned in various separate instances that the complex "pike nose" was tricky to construct and as a result exact angles and dimensions could vary a fair bit between individual tanks.<br /><br />Probably one of the many reasons castings were popular.Kellomieshttps://www.blogger.com/profile/04915110653443066212noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-8839926011460864182016-05-18T09:28:34.115-04:002016-05-18T09:28:34.115-04:00Yeah, the IS-3 was built for wartime service, when...Yeah, the IS-3 was built for wartime service, when the requirement is to last for thousands of kilometers. Peacetime service needed tens of thousands. Looks like the IS-2 could meet that requirement and the IS-3 could not.<br /><br />As for a 100 mm test, I too have never seen any evidence of such an event. The ballistics requirements for heavy tanks were to resist the D-25 and KwK 43, not the D-10. Perhaps later, a scrapped IS-3 used as a range target suffered such a hit? Peterhttps://www.blogger.com/profile/09622237223229485503noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-50063714730941498142016-05-18T06:11:35.631-04:002016-05-18T06:11:35.631-04:00The introduction of the successor IS-8/T-10 might ...The introduction of the successor IS-8/T-10 might of been related... though I remember reading that the IS-3 hull proved to be a bit too extreme in its design and, due to lacking sufficient structural rigidity and suchlike, prone to problematic levels of deformation in the long run.Kellomieshttps://www.blogger.com/profile/04915110653443066212noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-57404656068745291302016-05-18T05:27:03.269-04:002016-05-18T05:27:03.269-04:00Very interesting, note how IS-3 is referred as a &...Very interesting, note how IS-3 is referred as a "modernised IS-2".<br /><br />Is there a final answer on why production of IS-3 was terminated? Svirin states that there was a ballistic test where a 100mm round hit the weld at the front chassis, destroying it completely. After this confidence in the vehicle was broken and never restored. <br /><br />I have never seen any evidence of this test. Other people have added that the weld was faulty in this vehicle, or that the welding was improved to fix the problem.<br /><br />Other sources point out at issues that prevented proper "exploitation" of the type. The chassis was prone to cracks due to it's new features.<br /><br />Thanks.Alejandrohttps://www.blogger.com/profile/05537203226584815118noreply@blogger.comtag:blogger.com,1999:blog-5030145265861917845.post-68208642676014613292016-05-17T12:15:28.167-04:002016-05-17T12:15:28.167-04:00There is an error about the total amount of heavy ...There is an error about the total amount of heavy tanks and SPG in the third point on May. It should be 600 instead of 500.<br />Regards.Motzkorhttps://www.blogger.com/profile/18316989921665401048noreply@blogger.com