\u0642\u0648\u0629 \u0627\u0644\u0634\u062f:<\/strong> \u0647\u0630\u0627 \u0647\u0648 \u0623\u0642\u0635\u0649 \u0625\u062c\u0647\u0627\u062f \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062a\u062d\u0645\u0644\u0647 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u0639\u0646\u062f \u0633\u062d\u0628\u0647 \u0623\u0648 \u062a\u0645\u062f\u064a\u062f\u0647. \u0628\u0627\u0644\u0646\u0633\u0628\u0629 \u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0627\u0644\u0641\u0648\u0644\u0627\u0630\u064a\u0629 \u0627\u0644\u0646\u0645\u0648\u0630\u062c\u064a\u0629\u060c \u062a\u062a\u0631\u0627\u0648\u062d \u0642\u0648\u0629 \u0627\u0644\u0634\u062f \u0645\u0646 400 \u0625\u0644\u0649 550 \u0645\u064a\u062c\u0627 \u0628\u0627\u0633\u0643\u0627\u0644 (MPa).<\/p>\n<\/li>\n \u0642\u0648\u0629 \u0627\u0644\u0627\u0646\u0636\u063a\u0627\u0637:<\/strong> \u0639\u0644\u0649 \u0627\u0644\u0631\u063a\u0645 \u0645\u0646 \u0623\u0646 \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0644\u0627 \u064a\u062a\u0645 \u062a\u062d\u0645\u064a\u0644\u0647\u0627 \u0639\u0627\u062f\u0629\u064b \u0641\u064a \u062d\u0627\u0644\u0629 \u0627\u0644\u0627\u0646\u0636\u063a\u0627\u0637 \u0645\u062b\u0644 \u0627\u0644\u0623\u0639\u0645\u062f\u0629\u060c \u0625\u0644\u0627 \u0623\u0646\u0647 \u0645\u0646 \u0627\u0644\u0645\u0647\u0645 \u0641\u0647\u0645 \u0627\u0644\u0645\u062a\u0627\u0646\u0629 \u0627\u0644\u0643\u0644\u064a\u0629. \u062a\u062a\u0639\u0627\u0645\u0644 \u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0645\u0639 \u0627\u0644\u0623\u062d\u0645\u0627\u0644 \u0627\u0644\u0627\u0646\u0636\u063a\u0627\u0637\u064a\u0629 \u0628\u0634\u0643\u0644 \u062c\u064a\u062f \u0644\u0644\u063a\u0627\u064a\u0629\u060c \u0645\u0645\u0627 \u064a\u062a\u0637\u0627\u0628\u0642 \u0628\u0634\u0643\u0644 \u0639\u0627\u0645 \u0645\u0639 \u0642\u0648\u0629 \u0627\u0644\u0634\u062f \u0644\u0623\u0646 \u0627\u0644\u0641\u0648\u0644\u0627\u0630 \u0645\u062a\u0633\u0627\u0648\u064a \u0627\u0644\u062e\u0648\u0627\u0635.<\/p>\n<\/li>\n \u0642\u0648\u0629 \u0627\u0644\u0645\u0631\u062f\u0648\u062f:<\/strong> \u062a\u062d\u062f\u062f \u0646\u0642\u0637\u0629 \u0627\u0644\u062e\u0636\u0648\u0639 \u062d\u064a\u062b \u064a\u0628\u062f\u0623 \u0627\u0644\u062a\u0634\u0648\u0647 \u0627\u0644\u062f\u0627\u0626\u0645. \u0628\u0627\u0644\u0646\u0633\u0628\u0629 \u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f\u060c \u062a\u0646\u062e\u0641\u0636 \u0645\u0642\u0627\u0648\u0645\u0629 \u0627\u0644\u062e\u0636\u0648\u0639 \u0628\u0634\u0643\u0644 \u0639\u0627\u0645 \u062d\u0648\u0644 250 \u0625\u0644\u0649 350 \u0645\u064a\u062c\u0627 \u0628\u0627\u0633\u0643\u0627\u0644.<\/p>\n<\/li>\n<\/ul>\n \u064a\u0645\u0643\u0646 \u0623\u0646 \u062a\u062e\u062a\u0644\u0641 \u0642\u064a\u0645 \u0627\u0644\u0645\u062a\u0627\u0646\u0629 \u0647\u0630\u0647 \u0628\u0646\u0627\u0621\u064b \u0639\u0644\u0649 \u0633\u064f\u0645\u0643 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 (\u0627\u0644\u062c\u062f\u0648\u0644 \u0627\u0644\u0632\u0645\u0646\u064a) \u0648\u0627\u0644\u0642\u0637\u0631 \u0648\u062f\u0631\u062c\u0627\u062a \u0627\u0644\u0641\u0648\u0644\u0627\u0630 \u0627\u0644\u0645\u062d\u062f\u062f\u0629 \u0627\u0644\u0645\u0633\u062a\u062e\u062f\u0645\u0629. \u062a\u063a\u0637\u064a \u0645\u0639\u0627\u064a\u064a\u0631 \u0627\u0644\u0635\u0646\u0627\u0639\u0629 \u0645\u062b\u0644 ASTM A53 \u062a\u0641\u0627\u0635\u064a\u0644 \u0627\u0644\u0645\u0648\u0627\u0635\u0641\u0627\u062a \u0648\u062a\u0636\u0645\u0646 \u0627\u0644\u062d\u062f \u0627\u0644\u0623\u062f\u0646\u0649 \u0645\u0646 \u0645\u0633\u062a\u0648\u064a\u0627\u062a \u0627\u0644\u0642\u0648\u0629.<\/p>\n \u0648\u0627\u0644\u0622\u0646\u060c \u062f\u0639\u0648\u0646\u0627 \u0646\u062a\u0646\u0627\u0648\u0644 \u062c\u0648\u0647\u0631 \u0627\u0644\u0633\u0624\u0627\u0644. \u0645\u0627 \u0645\u0642\u062f\u0627\u0631 \u0627\u0644\u0648\u0632\u0646 \u0627\u0644\u0630\u064a \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062d\u0645\u0644\u0647 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u0627\u0644\u062d\u062f\u064a\u062f\u064a \u0627\u0644\u0623\u0633\u0648\u062f\u061f<\/p>\n \u0644\u0627 \u064a\u0648\u062c\u062f \u0631\u0642\u0645 \u0648\u0627\u062d\u062f\u060c \u0628\u0644 \u064a\u0639\u062a\u0645\u062f \u0639\u0644\u0649 \u0639\u062f\u0629 \u0639\u0648\u0627\u0645\u0644 \u062d\u0627\u0633\u0645\u0629:<\/p>\n \u062a\u0623\u062a\u064a \u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0641\u064a \u062c\u062f\u0627\u0648\u0644 \u0645\u062e\u062a\u0644\u0641\u0629 (\u0639\u0644\u0649 \u0633\u0628\u064a\u0644 \u0627\u0644\u0645\u062b\u0627\u0644\u060c \u0627\u0644\u062c\u062f\u0648\u0644 40\u060c 80)\u060c \u0648\u0627\u0644\u062a\u064a \u062a\u062d\u062f\u062f \u0633\u0645\u0643 \u0627\u0644\u062c\u062f\u0627\u0631. \u0627\u0644\u062c\u062f\u0631\u0627\u0646 \u0627\u0644\u0633\u0645\u064a\u0643\u0629 \u062a\u0639\u0646\u064a \u0642\u062f\u0631\u0629 \u062a\u062d\u0645\u0644 \u0623\u0643\u0628\u0631.<\/p>\n \u064a\u0648\u0632\u0639 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u0630\u0648 \u0627\u0644\u0642\u0637\u0631 \u0627\u0644\u0623\u0643\u0628\u0631 \u0627\u0644\u0623\u062d\u0645\u0627\u0644 \u0628\u0634\u0643\u0644 \u0645\u062e\u062a\u0644\u0641. \u0639\u0644\u0649 \u0633\u0628\u064a\u0644 \u0627\u0644\u0645\u062b\u0627\u0644\u060c \u064a\u0645\u0643\u0646 \u0644\u0623\u0646\u0628\u0648\u0628 \u0645\u0646 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0628\u0642\u0637\u0631 2 \u0628\u0648\u0635\u0629 \u0623\u0646 \u064a\u062d\u0645\u0644 \u062d\u0645\u0648\u0644\u0629 \u0645\u062e\u062a\u0644\u0641\u0629 \u0639\u0646 \u0623\u0646\u0628\u0648\u0628 \u0628\u0642\u0637\u0631 6 \u0628\u0648\u0635\u0627\u062a \u0628\u0633\u0628\u0628 \u0645\u0633\u0627\u062d\u0629 \u0627\u0644\u0645\u0642\u0637\u0639 \u0627\u0644\u0639\u0631\u0636\u064a.<\/p>\n \u0647\u0644 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u064a\u062a\u062d\u0645\u0644 \u062d\u0645\u0648\u0644\u0629 \u0633\u0627\u0643\u0646\u0629 (\u0645\u062b\u0644 \u0648\u0632\u0646 \u064a\u0633\u062a\u0646\u062f \u0639\u0644\u064a\u0647)\u060c \u0623\u0645 \u0623\u0646\u0647 \u062a\u062d\u062a \u062d\u0645\u0648\u0644\u0629 \u062f\u064a\u0646\u0627\u0645\u064a\u0643\u064a\u0629 (\u0645\u062b\u0644 \u0627\u0644\u0627\u0647\u062a\u0632\u0627\u0632 \u0623\u0648 \u062a\u063a\u064a\u0631\u0627\u062a \u0627\u0644\u0636\u063a\u0637)\u061f \u062a\u0633\u0645\u062d \u0627\u0644\u0623\u062d\u0645\u0627\u0644 \u0627\u0644\u0633\u0627\u0643\u0646\u0629 \u0628\u0634\u0643\u0644 \u0639\u0627\u0645 \u0628\u0642\u064a\u0645 \u062d\u0645\u0648\u0644\u0629 \u0622\u0645\u0646\u0629 \u0623\u0639\u0644\u0649.<\/p>\n \u062a\u0624\u062b\u0631 \u0643\u064a\u0641\u064a\u0629 \u062f\u0639\u0645 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u0639\u0644\u0649 \u0645\u0642\u062f\u0627\u0631 \u0627\u0644\u062d\u0645\u0648\u0644\u0629 \u0627\u0644\u062a\u064a \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062a\u062d\u0645\u0644\u0647\u0627 \u062f\u0648\u0646 \u0627\u0646\u062d\u0646\u0627\u0621 \u0623\u0648 \u0627\u0644\u062a\u0648\u0627\u0621. \u0639\u0644\u0649 \u0633\u0628\u064a\u0644 \u0627\u0644\u0645\u062b\u0627\u0644\u060c \u062a\u062e\u062a\u0644\u0641 \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u0645\u062f\u0639\u0648\u0645\u0629 \u0645\u0646 \u0643\u0644\u0627 \u0627\u0644\u0637\u0631\u0641\u064a\u0646 \u0639\u0646 \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u0643\u0627\u0628\u0648\u0644\u064a\u0629.<\/p>\n \u064a\u0639\u0632\u0632 \u0627\u0644\u0641\u0648\u0644\u0627\u0630 \u0639\u0627\u0644\u064a \u0627\u0644\u062c\u0648\u062f\u0629 \u0623\u0648 \u0639\u0645\u0644\u064a\u0627\u062a \u0627\u0644\u062a\u0635\u0646\u064a\u0639 \u0627\u0644\u0645\u062a\u0641\u0648\u0642\u0629 \u0645\u0646 \u0627\u0644\u0642\u0648\u0629.<\/p>\n \u0636\u0639 \u0641\u064a \u0627\u0639\u062a\u0628\u0627\u0631\u0643 \u0623\u0646\u0627\u0628\u064a\u0628 \u062d\u062f\u064a\u062f \u0623\u0633\u0648\u062f \u062c\u062f\u0648\u0644 40 \u0628\u0648\u0635\u0629 2 \u0628\u0648\u0635\u0629<\/strong>:<\/p>\n \u0627\u0644\u0642\u0637\u0631 \u0627\u0644\u062e\u0627\u0631\u062c\u064a (OD): 2.375 \u0628\u0648\u0635\u0629<\/p>\n<\/li>\n \u0633\u064f\u0645\u0643 \u0627\u0644\u062c\u062f\u0627\u0631: 0.154 \u0628\u0648\u0635\u0629<\/p>\n<\/li>\n \u0642\u0648\u0629 \u0627\u0644\u062e\u0636\u0648\u0639: 300 \u0645\u064a\u062c\u0627 \u0628\u0627\u0633\u0643\u0627\u0644 (\u0646\u0645\u0648\u0630\u062c\u064a)<\/p>\n<\/li>\n<\/ul>\n \u0627\u0633\u062a\u062e\u062f\u0627\u0645 \u0627\u0644\u0635\u064a\u063a \u0627\u0644\u0647\u0646\u062f\u0633\u064a\u0629 (\u0644\u0633\u0639\u0629 \u0627\u0644\u062d\u0645\u0644 \u0627\u0644\u0645\u062d\u0648\u0631\u064a):<\/p>\n \u0633\u0639\u0629 \u0627\u0644\u062d\u0645\u0648\u0644\u0629 \u0627\u0644\u0645\u062d\u0648\u0631\u064a\u0629\u060c P = A \u00d7 \u03c3_yield<\/strong><\/p>\n \u0623\u064a\u0646:<\/p>\n A = \u0645\u0633\u0627\u062d\u0629 \u0627\u0644\u0645\u0642\u0637\u0639 \u0627\u0644\u0639\u0631\u0636\u064a \u0644\u062c\u062f\u0627\u0631 \u0627\u0644\u0623\u0646\u0628\u0648\u0628<\/p>\n<\/li>\n \u03c3_\u0627\u0644\u0645\u0631\u062f\u0648\u062f = \u0642\u0648\u0629 \u0627\u0644\u0645\u0631\u062f\u0648\u062f<\/p>\n<\/li>\n<\/ul>\n \u062d\u0633\u0627\u0628 \u0645\u0633\u0627\u062d\u0629 \u0627\u0644\u0645\u0642\u0637\u0639 \u0627\u0644\u0639\u0631\u0636\u064a (\u0645\u0633\u0627\u062d\u0629 \u0627\u0644\u062c\u062f\u0627\u0631):<\/p>\n A<\/span>=<\/span><\/span>\u03c0<\/span>\u00d7<\/span><\/span>(<\/span><\/span>O<\/span>D\u00b2<\/span>-<\/span>I<\/span>D\u00b2<\/span><\/span>)\/4<\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/p><\/blockquote>\n \u0627\u0644\u0645\u064f\u0639\u0631\u0650\u0651\u0641 (\u0627\u0644\u0642\u0637\u0631 \u0627\u0644\u062f\u0627\u062e\u0644\u064a) = OD - 2 \u00d7 \u0633\u064f\u0645\u0643 \u0627\u0644\u062c\u062f\u0627\u0631 \u0627\u0644\u0645\u0633\u0627\u062d\u0629 \u0628\u0627\u0644\u0628\u0648\u0635\u0629 \u0627\u0644\u0645\u0631\u0628\u0639\u0629:<\/p>\n A<\/span>=<\/span><\/span>\u03c0<\/span>\u00d7<\/span><\/span>(<\/span>2.375\u00b2<\/span><\/span><\/span><\/span><\/span>-<\/span>2.067\u00b2)\/4<\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span>\u2248<\/span><\/span>1.15<\/span>\u0641\u064a\u00b2<\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/p><\/blockquote>\n \u062a\u062d\u0648\u064a\u0644 \u0645\u0642\u0627\u0648\u0645\u0629 \u0627\u0644\u062e\u0636\u0648\u0639 \u0625\u0644\u0649 \u0631\u0637\u0644 \u0644\u0643\u0644 \u0628\u0648\u0635\u0629 \u0645\u0631\u0628\u0639\u0629 (1 \u0645\u064a\u062c\u0627 \u0628\u0627\u0633\u0643\u0627\u0644 = 145 \u0631\u0637\u0644 \u0644\u0643\u0644 \u0628\u0648\u0635\u0629 \u0645\u0631\u0628\u0639\u0629):<\/p>\n 300<\/span>\u0645\u064a\u062c\u0627 \u0628\u0627\u0633\u0643\u0627\u0644<\/span><\/span>\u00d7<\/span><\/span>145<\/span>=<\/span><\/span>43<\/span>,<\/span>500<\/span>\u0631\u0637\u0644<\/span><\/span><\/span><\/p><\/blockquote>\n \u0625\u0630\u0646,<\/p>\n P<\/span>=<\/span><\/span>1.15<\/span>\u00d7<\/span><\/span>43<\/span>,<\/span>500<\/span>=<\/span><\/span>50<\/span>,<\/span>025<\/span>\u0627\u0644\u0631\u0637\u0644<\/span><\/span>\u2248<\/span><\/span>50<\/span>,<\/span>000<\/span>\u0627\u0644\u0631\u0637\u0644<\/span><\/span><\/span><\/p><\/blockquote>\n \u0648\u0647\u0630\u0627 \u064a\u0639\u0646\u064a\u060c \u0646\u0638\u0631\u064a\u064b\u0627\u060c \u0623\u0646 \u0647\u0630\u0627 \u0627\u0644\u0623\u0646\u0628\u0648\u0628 \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062a\u062d\u0645\u0644 \u062d\u0648\u0627\u0644\u064a 50,000 \u062c\u0646\u064a\u0647<\/strong> \u0645\u0646 \u0627\u0644\u062d\u0645\u0644 \u0627\u0644\u0645\u062d\u0648\u0631\u064a \u0642\u0628\u0644 \u0627\u0644\u062e\u0636\u0648\u0639.<\/p>\n \u0645\u0644\u0627\u062d\u0638\u0629: \u0647\u0630\u0647 \u0639\u0645\u0644\u064a\u0629 \u062d\u0633\u0627\u0628\u064a\u0629 \u0645\u0628\u0633\u0637\u0629. \u0645\u0646 \u0627\u0644\u0646\u0627\u062d\u064a\u0629 \u0627\u0644\u0639\u0645\u0644\u064a\u0629\u060c \u062a\u0642\u0644\u0644 \u0639\u0648\u0627\u0645\u0644 \u0627\u0644\u0633\u0644\u0627\u0645\u0629 \u0648\u062a\u0639\u0642\u064a\u062f\u0627\u062a \u0627\u0644\u062d\u0645\u0648\u0644\u0629 \u0641\u064a \u0627\u0644\u0639\u0627\u0644\u0645 \u0627\u0644\u062d\u0642\u064a\u0642\u064a \u0645\u0646 \u0633\u0639\u0629 \u0627\u0644\u062d\u0645\u0648\u0644\u0629 \u0627\u0644\u0642\u0627\u0628\u0644\u0629 \u0644\u0644\u0627\u0633\u062a\u062e\u062f\u0627\u0645 \u0628\u0634\u0643\u0644 \u0643\u0628\u064a\u0631.<\/p>\n \u0648\u0644\u0625\u0639\u0637\u0627\u0626\u0643 \u0635\u0648\u0631\u0629 \u0623\u0648\u0636\u062d\u060c \u0642\u0645\u062a \u0628\u062a\u062c\u0645\u064a\u0639 \u062c\u062f\u0648\u0644 \u0645\u0642\u0627\u0631\u0646\u0629 \u064a\u0633\u0644\u0637 \u0627\u0644\u0636\u0648\u0621 \u0639\u0644\u0649 \u0645\u0639\u0644\u0645\u0627\u062a \u0627\u0644\u0642\u0648\u0629 \u0648\u0627\u0644\u0648\u0632\u0646 \u0627\u0644\u0631\u0626\u064a\u0633\u064a\u0629 \u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0645\u0642\u0627\u0628\u0644 \u0645\u0648\u0627\u062f \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u0634\u0627\u0626\u0639\u0629 \u0627\u0644\u0623\u062e\u0631\u0649.<\/p>\n3. \u0645\u0627 \u0645\u0642\u062f\u0627\u0631 \u0627\u0644\u0648\u0632\u0646 \u0627\u0644\u0630\u064a \u064a\u0645\u0643\u0646 \u0623\u0646 \u062a\u062d\u0645\u0644\u0647 \u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f\u061f \u0627\u0644\u0639\u0648\u0627\u0645\u0644 \u0627\u0644\u0645\u0624\u062b\u0631\u0629 \u0639\u0644\u0649 \u0633\u0639\u0629 \u0627\u0644\u062d\u0645\u0648\u0644\u0629<\/h2>\n
\u062c\u062f\u0648\u0644 \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0648\u0633\u064f\u0645\u0643\u0647\u0627<\/h3>\n
\u0627\u0644\u0642\u0637\u0631<\/h3>\n
\u0646\u0648\u0639 \u0627\u0644\u062d\u0645\u0648\u0644\u0629<\/h3>\n
\u0634\u0631\u0648\u0637 \u0627\u0644\u062f\u0639\u0645<\/h3>\n
\u062f\u0631\u062c\u0629 \u0627\u0644\u0645\u0648\u0627\u062f \u0648\u062c\u0648\u062f\u0629 \u0627\u0644\u062a\u0635\u0646\u064a\u0639<\/h3>\n
\u062d\u0633\u0627\u0628 \u0633\u0639\u0629 \u0627\u0644\u062d\u0645\u0648\u0644\u0629: \u0645\u062b\u0627\u0644 \u0645\u0628\u0633\u0637<\/h3>\n
\n
\n
= 2.375 - 2 \u00d7 0.154 = 2.067 \u0628\u0648\u0635\u0629<\/p>\n![\"\u0645\u0627](\"https:\/\/www.ductileironsuppliers.com\/wp-content\/uploads\/2025\/06\/tgrvf-rb9t6.webp\")
<\/a>4. \u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u062d\u062f\u064a\u062f \u0627\u0644\u0623\u0633\u0648\u062f \u0645\u0642\u0627\u0628\u0644 \u0645\u0648\u0627\u062f \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0627\u0644\u0634\u0627\u0626\u0639\u0629 \u0627\u0644\u0623\u062e\u0631\u0649: \u062a\u062d\u0644\u064a\u0644 \u0645\u0642\u0627\u0631\u0646<\/h2>\n