{"id":14692,"date":"2026-08-25T15:10:15","date_gmt":"2026-08-25T15:10:15","guid":{"rendered":"https:\/\/www.jstconsultancy.cz\/?p=14692"},"modified":"2026-08-25T21:17:51","modified_gmt":"2026-08-25T21:17:51","slug":"round-or-square-hot-zone","status":"publish","type":"post","link":"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/en\/round-or-square-hot-zone\/","title":{"rendered":"Round or square hot zone?"},"content":{"rendered":"<p>Discussions about which is more advantageous, a<strong> round<\/strong> chamber or a <strong>square<\/strong> chamber, have been going on for ages. What is interesting is that even though I was responsible for purchasing furnaces for 20 years, no furnace supplier has ever presented me with a meaningful analysis that would show the differences, advantages or disadvantages of the individual variants. So I set about it myself. The model case is on a die casting mold insert measuring 442*521*1905 mm, weighing ~3,400 kg. We will assume that both furnaces, <strong>round<\/strong> and <strong>square,<\/strong> have comparable:<\/p>\n<ul>\n<li>installed heating capacity,<\/li>\n<li>10\u201315 bar N\u2082 quenching capacity<\/li>\n<li>equally efficient nitrogen\/water heat exchanger<\/li>\n<li>similar maximum quenching turbine output<\/li>\n<li>transverse usable dimensions of 1200xx1200 mm.<\/li>\n<\/ul>\n<p>If the same size were to fit into a <strong>round<\/strong> chamber, the hot zone diameter would have to be at least 1697 mm dia. The heat exchange surface of a<strong> round<\/strong> furnace would be 22% larger than a <strong>square<\/strong> one. For the furnace design, this means that a <strong>square<\/strong> hot zone would have<\/p>\n<ul>\n<li>less insulation,<\/li>\n<li>lower losses<\/li>\n<li>lower heat capacity,<\/li>\n<li>less N\u2082,<\/li>\n<li>less hot gas that must be circulated during quenching<\/li>\n<\/ul>\n<p>The volume of a <strong>square<\/strong> heating zone with a length of 2,000 mm will be 2.88 m3, a circular one 4.52 m3. However, what will be a problem will be the distance from the heating elements. Heat transfer is calculated according to this equation:<\/p>\n<p><strong>Q<sub>rad<\/sub> <\/strong><strong>\u200b<\/strong><strong>= <\/strong><strong>\u03c3*\u03b5 <sub>eff \u00a0<\/sub>*A * F<sub>12<\/sub>*<\/strong><strong>\u200b<\/strong><strong>(<\/strong><strong>T<sub>h<\/sub><sup>4<\/sup><\/strong><strong>\u200b<\/strong><strong>\u2212<\/strong><strong>T<sub>p<\/sub><sup>4<\/sup><\/strong><strong>\u200b<\/strong><strong>)<\/strong><\/p>\n<p>wher:<\/p>\n<ul>\n<li><strong>\u03c3<\/strong> is <strong>Stefanova\u2013Boltzmannova konstanta<\/strong> = 5,67 * 10<sup>\u22128 <\/sup>Wm<sup>\u22122<\/sup>K<sup>\u22124<\/sup><\/li>\n<li><strong>\u03b5<sub>eff<\/sub><\/strong> is the effective emissivity<\/li>\n<li><strong>A <\/strong>surface in\u00a0m<sup>2<\/sup><\/li>\n<li><strong>F<sub>12<\/sub><\/strong> &#8211; view factor<\/li>\n<li><strong>T<sub>h<\/sub><\/strong> \u2013 temperature of heating elements<\/li>\n<li><strong>T<sub>p<\/sub><\/strong> \u2013 body surface temperature<\/li>\n<\/ul>\n<p><strong>View Factor<\/strong> <strong>F<sub>12<\/sub><\/strong>will therefore have a significant effect on the uniformity of heating \u2013 see figure no.\u00a01.<\/p>\n<p><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14677\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-300x225.png\" alt=\"\" width=\"300\" height=\"225\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-300x225.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-1024x768.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-768x576.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-195x146.png 195w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-50x38.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-100x75.png 100w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-960x720.png 960w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-250x188.png 250w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09-500x375.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_19_09.png 1448w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong><em><u>Fig. 1<\/u><\/em><\/strong><em> \u2013 Dependence of <strong>F<sub>12<\/sub><\/strong> on the distance from the heating elements, where <strong>H<\/strong> is the perpendicular distance between the heating elements and the surface of the part and <strong>L<\/strong> is the characteristic dimension of the surface, in our example 2000 mm<\/em><\/p>\n<p>The smaller the <strong>H\/L<\/strong>, the greater the portion of the radiated energy from one surface directly \u201csees\u201d the other surface, i.e. the higher the <strong>View factor<\/strong>. For a very small gap between two equally large parallel surfaces, the <strong>H\/L<\/strong> ratio will approach zero and the <strong>View Factor F<sub>12<\/sub><\/strong> will approach 1.<\/p>\n<p>On the contrary, at a large distance from the heater, the<strong> H\/L<\/strong> ratio increases and the <strong>View Factor F<sub>12<\/sub><\/strong> decreases. If we have a three-dimensional space, then we also have 3 different <strong>View Factors<\/strong>,<strong> Hx\/Lx<\/strong>, <strong>Hy\/Ly<\/strong> and <strong>Hz\/Lz,<\/strong> and these will affect the heating efficiency. The table (Fig.1) shows that, for example, at a distance from the heater of 300 mm, <strong>we will lose 25% of the radiant heat flux<\/strong>. If this distance is approximately the same on all sides of the part, the heating will be uniform, if these distances are different, the heating will be uneven.<\/p>\n<p>With a <strong>square<\/strong> chamber, we can get close to this ideal, but <strong>never with a round chamber.<\/strong> For a round hot zone, the negative effect is that we have different distances from the heating, with different <strong>View Factor F<sub>12<\/sub>,<\/strong> and therefore the overall radiation efficiency will automatically be lower. This will of course also be reflected in the energy consumption for heating. The result of the calculation is in this infographic. For the same cycle, the round chamber will have a consumption <strong>of 0.315 MWh higher<\/strong>, and the process time will be <strong>9.8% longer.<\/strong><\/p>\n<p><strong><em><u><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14695\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-300x225.png\" alt=\"\" width=\"300\" height=\"225\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-300x225.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-1024x768.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-768x576.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-195x146.png 195w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-50x38.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-100x75.png 100w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-960x720.png 960w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-250x188.png 250w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1-500x375.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_04_43-v1.png 1448w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/u><\/em><\/strong><\/p>\n<p><strong><em><u>Fig. 2<\/u><\/em><\/strong><em> \u2013 Comparison of differences in part heating in a <strong>square<\/strong> and <strong>round<\/strong> chamber<\/em><\/p>\n<p>A 9.8% shorter cycle in a <strong>square<\/strong> chamber means I can do 35 more cycles per year, saving 12.6% energy per cycle.<\/p>\n<p><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14681\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-300x225.png\" alt=\"\" width=\"300\" height=\"225\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-300x225.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-1024x768.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-768x576.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-195x146.png 195w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-50x38.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-100x75.png 100w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-960x720.png 960w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-250x188.png 250w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46-500x375.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-23.-8.-2026-15_52_46.png 1448w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14683\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-300x64.png\" alt=\"\" width=\"300\" height=\"64\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-300x64.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-1024x218.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-768x164.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-260x55.png 260w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-50x11.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-150x32.png 150w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743-500x106.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/Snimek-obrazovky-2026-08-25-101743.png 1536w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong><em><u>Fig. 3<\/u><\/em><\/strong><em> \u2013 Graphical representation of the differences in the quenching cycle between a <strong>square<\/strong> and a <strong>round<\/strong> chamber<br \/>\n<\/em><strong><em><u>Table 1<\/u><\/em><\/strong><em> \u2013 KPI indicators for both types of hot zones<\/em><\/p>\n<p>With an initial electricity price of 4 CZK\/kWh (0,166 \u20ac\/kWh) and a 2% annual inflationary increase in energy prices, the cumulative 20-year electricity savings are approximately <strong>11.1 million CZK<\/strong>, i.e. about 0.44 million EUR. So it makes sense to think about it.<\/p>\n<p>And what about cooling and deformations? Here we are no longer interested in radiation, but primarily in heat dissipation, according to the equation <strong>Q = h * A *(Tpart\u200b\u2212Tgas\u200b).<\/strong> The convective heat transfer coefficient <strong>h<\/strong> between the gas and the part will depend on a number of parameters, but primarily on the <strong>gas velocity, N2 pressure, flow direction relative to the surface, turbulence, geometry of the part and its position relative to the gas flow.<\/strong><\/p>\n<p>The problem with both <strong>square<\/strong> and<strong> circular<\/strong> heating zones is that the gas flows along the path of least resistance, instead of flowing where we need to dissipate heat. The result can be different cooling rates of individual walls, different martensitic transformation, higher deformation, higher temperature gradients, uneven hardness in large cross-sections. For GIGA molds, this will be much more important than the difference in energy efficiency. As can be seen from the graph, this phase will also be <strong>more effective in a square chamber<\/strong> and the cooling time will be reduced by more than an hour, equivalent to 17%.<\/p>\n<p>TAV Vacuum Furnaces has designed a<strong> square<\/strong> chamber for these purposes with an <strong>adaptive flap<\/strong> system that allows the hardening to be adapted to the geometry of the part in the furnace. This is especially important for such large parts. With a heating zone height of 1200 mm, it is obvious that the part cannot always be placed in the center of the furnace. If the hardened part is placed on a grid placed directly on supports in the lower part of the chamber, under normal circumstances the gas would flow outside the insert, again along the path of least resistance. However, with the TAV solution, there is the possibility of using <strong>adaptive flaps<\/strong>, where I can determine where the gas will enter the chamber with respect to the shape and position of the part. It is even possible to control their opening and position based on the temperature sensing of the part by batch thermocouples. If the temperature difference <strong>\u0394T<sub>TB<\/sub> = T<sub>top<\/sub> \u2212T<sub>bottom<\/sub>, or \u0394T<sub>LR<\/sub> = T<sub>left<\/sub> \u2212T<\/strong><sub><strong>righ<\/strong>t<\/sub> were monitored by batch thermocouples, it would be possible to open or close the flaps, control the fan speed, or change the N2 pressure according to this difference, and thus adapt the cooling of the parts directly according to their geometry. Of course, this can only be done with a <strong>square<\/strong> chamber, not with a <strong>circular<\/strong> one.<\/p>\n<p><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14685\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-300x105.png\" alt=\"\" width=\"300\" height=\"105\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-300x105.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-1024x357.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-768x268.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-260x91.png 260w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-50x17.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-150x52.png 150w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1-500x174.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/529_Obrazek1.png 1058w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p><strong><em><u>Fig. 4<\/u><\/em><\/strong><em> \u2013 Comparison of standard <strong>square<\/strong> and <strong>circular<\/strong> chamber solutions without adaptive flaps<\/em><\/p>\n<p>What I have said is of course not to say that a <strong>round<\/strong> chamber is not a good solution. On the contrary. If I am buying a furnace for a commercial heat treatment shop, where there is a very diverse range of products, then this is a very good solution. However, if I know in advance what type of parts, with what geometry I will process, and I make a similar analysis, the clear decision will be for a<strong> square<\/strong> chamber.<\/p>\n<p>In a <strong>square<\/strong> hot zone, the hot zone provides a geometrically more uniform relationship between the heating elements and the hardened part. For large rectangular parts of molds supported by a base grid, the<strong> square<\/strong> hot zone provides a closer match between the geometry of the heating zone and the geometry of the load, which improves the potential for uniform radiant heating and cooling, which cannot be found in a <strong>round<\/strong> chamber.<\/p>\n<p>And what is the difference between the theoretical temperature uniformity of the furnace according to <strong>AMS 2750<\/strong> and its geometry? The standard <strong>TUS<\/strong> is measured in a qualified working zone on an empty furnace without load. But it says nothing about the behavior of the furnace when processing a specific 3.4t GIGA block. A <strong>circular<\/strong> furnace will also have a <strong>TUS of +\/- 5 C<\/strong>, as will a <strong>square<\/strong> zone, yet the heating of the actual tool in it may be significantly less uniform. Why? Because after inserting a large block, the block will shade the heating elements, changing the irradiation ratio, the grid will shade the bottom surface, some walls of the part see the heating elements directly, others through reflections and re-radiation.<\/p>\n<p>This is exactly the reason why, for such a demanding application, we should distinguish between <strong>TUS<\/strong> according to <strong>AMS 275<\/strong>0, and <strong>Load thermal uniformity<\/strong>, i.e. the actual state of <strong>T<sub>Surface,top\u200b<\/sub>,Ts<sub>urface,bottom<\/sub>\u200b,Ts<sub>urface,left\u200b<\/sub>,Ts<sub>urface,right<\/sub>\u200b,T<sub>core<\/sub>\u200b<\/strong> for the reference charge during the actual process.<\/p>\n<p>The analysis results in one more finding. According to <strong>Nadca-207<\/strong>, the criterion for cooling must be to get from the austenitization temperature to 540\u00b0C<strong> in 18 min<\/strong>. In neither case will we achieve this for a block with a characteristic dimension of 442 mm. For a <strong>square<\/strong> chamber it will be <strong>25 min,<\/strong>\u00a0for a <strong>round<\/strong> one<strong> 29 min.<\/strong> Is there a problem with that? If we insist on<strong> H11\/H13<\/strong>, then yes. If we change the material of the part to steels such as <strong>Divear, DAIDO-GIGA<\/strong> or <strong>MT1<\/strong> from Kind&amp;Co, then although we will not comply with the <strong>Nadca-207<\/strong> regulation, we will get <strong>what we need metallurgically.<\/strong><\/p>\n<p>So what conclusion can we draw? This can be seen in this last picture.<\/p>\n<p><a href=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33.png\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-medium wp-image-14687\" src=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-300x225.png\" alt=\"\" width=\"300\" height=\"225\" srcset=\"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-300x225.png 300w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-1024x768.png 1024w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-768x576.png 768w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-195x146.png 195w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-50x38.png 50w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-100x75.png 100w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-960x720.png 960w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-250x188.png 250w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33-500x375.png 500w, https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/wp-content\/uploads\/2026\/08\/ChatGPT-Image-25.-8.-2026-09_58_33.png 1448w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n<p>=======================================================================================================<br \/>\n<strong>Are you solving a similar problem? I will help you with the analysis\u2026<\/strong><br \/>\n<img decoding=\"async\" class=\"emoji\" role=\"img\" draggable=\"false\" src=\"https:\/\/s.w.org\/images\/core\/emoji\/17.0.2\/svg\/2714.svg\" alt=\"&#x2714;\" \/>\u00a040+ years of experience in the field<br \/>\n<img decoding=\"async\" class=\"emoji\" role=\"img\" draggable=\"false\" src=\"https:\/\/s.w.org\/images\/core\/emoji\/17.0.2\/svg\/2714.svg\" alt=\"&#x2714;\" \/>\u00a030+ years of experience\u2026 HT-PROGRES, Bodycote, Galvamet<br \/>\n<img decoding=\"async\" class=\"emoji\" role=\"img\" draggable=\"false\" src=\"https:\/\/s.w.org\/images\/core\/emoji\/17.0.2\/svg\/2714.svg\" alt=\"&#x2714;\" \/>\u00a0cooperation\u2026 V\u0160B, Czechimplant, ECM Technologies, TAV Vacuum Furnaces, GHC Invest<br \/>\n<img decoding=\"async\" class=\"emoji\" role=\"img\" draggable=\"false\" src=\"https:\/\/s.w.org\/images\/core\/emoji\/17.0.2\/svg\/2714.svg\" alt=\"&#x2714;\" \/>\u00a012+ years of expert activity<br \/>\nWant to ask for a solution or want a non-binding consultation? Click on this link, I will usually respond within 24 hours.\u00a0<a href=\"mailto:stanislav.jirka@gmail.com\">Contact email<\/a><br \/>\n========================================================================================================<br \/>\n<strong>Ji\u0159\u00ed Stanislav, Ing. CSc.<br \/>\n<\/strong>Consultant and forensic expert<br \/>\n========================================================================================================<\/p>\n<p>25\/8\/2026<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Discussions about which is more advantageous, a round chamber or a square chamber, have been going on for ages. What is interesting is that even though<\/p>\n","protected":false},"author":12,"featured_media":14690,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[338,332],"tags":[],"class_list":["post-14692","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-equipment-en","category-tav-furnaces-en"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Round or square hot zone? - JST Consultancy<\/title>\n<meta name=\"robots\" content=\"noindex, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<meta property=\"og:locale\" content=\"cs_CZ\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Round or square hot zone? - JST Consultancy\" \/>\n<meta property=\"og:description\" content=\"Discussions about which is more advantageous, a round chamber or a square chamber, have been going on for ages. 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