{"id":2659,"date":"2026-09-25T18:13:56","date_gmt":"2026-09-25T18:13:56","guid":{"rendered":"https:\/\/endlfh.com\/2659\/"},"modified":"2026-09-25T18:13:56","modified_gmt":"2026-09-25T18:13:56","slug":"steel-for-construction-machinery-introduction-to-q345qe-bridge-steel-plate","status":"publish","type":"post","link":"https:\/\/endlfh.com\/fi\/2659\/","title":{"rendered":"Steel For Construction Machinery: Introduction To Q345qE Bridge Steel Plate"},"content":{"rendered":"

Steel for construction machinery: Introduction to Q345qE bridge steel plate<\/p>\n

When carrying out the riveting and welding processing business of engineering machinery structural parts, due to the extremely large number of applications of Q345 steel plates and the very strict quality standards, many manufacturers will have technical accidents in selecting materials and performing welding operations once they enter the mass production stage . Engineering machinery structural parts Q345 steel plate riveting welding<\/strong> Engineering machinery structural parts Q345 steel plate riveting welding<\/strong> . This kind of weld cracking occurs and the component deformation value exceeds the standard limit. It has long been an inherent flaw that has been frequently criticized within this industry.<\/p>\n

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Don\u2019t confuse ingredients and brands<\/h2>\n<\/p>\n

\"\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a_Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027_Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df\"<\/p>\n

The difference between Q345B and Q345C lies in the temperature of the impact energy test. Level B is conducted at minus 20 degrees Celsius, while level C is conducted at zero degrees Celsius. Therefore, if you are making structural parts for engineering machinery in the north, it is recommended to directly go to level C or even level D. Do not save dozens of dollars.<\/p>\n

The carbon content is in the range of 0.12% to 0.2%, the manganese content is in the range of 1.2% to 1.6%, and the total value of phosphorus and sulfur is not more than 0.04%. It directly determines whether the weld can penetrate it and whether it has toughness. Therefore, when purchasing this material, you must check each item of data one by one.<\/p>\n

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Sheet thickness and delivery status<\/h2>\n<\/p>\n

The commonly used thickness of engineering machinery structural parts ranges from 10 mm to 80 mm. For thick plates exceeding 60 mm, attention must be paid to its Z-direction performance, and it is required to meet the standards of Z35 and above. The delivery state is generally hot-rolled, but in key stress-bearing parts, it is recommended to use normalized steel plates.<\/p>\n

\"Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027_Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df_\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a\"<\/p>\n

When purchasing, you should focus on the warranty. You need to confirm that the yield strength cannot be less than 345MPa, and the elongation cannot be less than 21%. If these two contents cannot meet the requirements, just return it directly. Don't be vague here.<\/p>\n

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Welding process parameters<\/h2>\n<\/p>\n

\"\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a_Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df_Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027\"<\/p>\n

Methods of using manual arc welding Engineering machinery steel: Q345qE bridge steel plate introduction, it is recommended to use two types of welding rods, J506 or J507; when performing submerged arc welding operations, the welding wire made of H08MnA and SJ101 flux should be matched.<\/p>\n

When the thickness of the steel plate is 10 mm, the current value used for welding should be controlled within the range of 180 amps to 220 amps. If it is a 30 mm thick steel plate, the current intensity needs to be adjusted to between 320 amps and 380 amps. Never try to use the same set of parameters to weld all workpieces with different thicknesses. This approach is not advisable.<\/p>\n

Before welding, the temperature needs to be preheated to above 80 degrees Celsius and not exceed 120 degrees Celsius. In the process of multi-layer welding, the temperature between layers must not exceed 250 degrees Celsius. In the case of multi-pass welding, the welding slag must be cleaned after each pass to ensure that there is no residue, because if there are residual pores, this is equivalent to a time bomb that will cause fatigue fracture.<\/p>\n

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Riveting and riveting combined<\/h2>\n<\/p>\n

Nowadays, in most cases, the hybrid connection method of bolting and welding has been changed, but in parts with relatively large vibration, using riveting is still more reliable. The selected rivet material is 20MnTiB or 40Cr. When applying the pretightening force, it should be operated according to 90% of the design value. Do not over-tighten the rivet.<\/p>\n

The distance from the rivet hole to the edge must not be less than twice the hole diameter. At the same time, the distance between the centers of two rivet holes must not be less than three times the hole diameter. The distance between the welding seam and the center of the rivet hole circle should be at least 50mm. Because if the heat-affected zones overlap, the strength will decrease.<\/p>\n

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Deformation control and quality inspection<\/h2>\n<\/p>\n

\"Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df_\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a_Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027\"<\/p>\n

\"Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027_\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a_Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df\"<\/p>\n

In the welding process of plates thicker than 60 mm, the phenomenon of welding deformation is the most troublesome problem. Therefore, we strongly recommend that you adopt a process strategy of preliminary cutting and welding first, and then final cutting.<\/p>\n

Regarding the calculation of welding shrinkage, the corresponding numerical space needs to be reserved in advance according to the ratio of 0.3% of the plate thickness. At the actual operation level, riveting welding of Q345 steel plates for engineering machinery structural parts<\/strong> requires a combination of symmetrical welding, jump welding and anti-deformation methods.<\/p>\n

The flaw detection operation should comply with the JB\/T5001 standard. The first-level weld must be fully penetrated and undergo UT testing. The second-level weld must be randomly inspected to detect 20% of pores and slag inclusions. These are the types of defects that occur frequently. If there is no fusion, it is also a high-frequency defect. If the number of repairs exceeds two times, it is recommended that the user directly scraps the replacement board.<\/p>\n

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Cost and lead time<\/h2>\n<\/p>\n

The price of spot 16mm Q345 is about 3800 to 4200 yuan per ton. This price will fluctuate with the market situation of manganese silicon. If you need to customize special thickness or Z-direction plate, the delivery cycle will need to increase by 7 to 15 days, so the purchase plan must be reported in advance.<\/p>\n

\"Q345qE\u6865\u6881\u94a2\u677f\u7279\u6027_Q345qE\u6865\u6881\u94a2\u677f\u5e94\u7528\u9886\u57df_\u5de5\u7a0b\u673a\u68b0\u7ed3\u6784\u4ef6Q345\u94a2\u677f\u94c6\u710a\"<\/p>\n

If it is a sporadic purchase of less than five tons, it is more convenient to go to a trader. But if you need to order large quantities, it would be more appropriate to directly contact major manufacturers such as Baowu, Shagang and Nanjing Iron and Steel. In this way, the price can save 50 to 80 yuan per unit. In terms of procedures, you must get the original version of the warranty letter stamped by the steel factory. Never accept copies of such documents.<\/p>\n

Our factory mainly does riveting and welding of structural parts of construction machinery. What channels do you usually use to pick up Q345 plates? If you encounter problems such as weld cracking, what methods are generally used to deal with it? You can exchange and discuss in the comment area. If you think this content is useful, please give it a like.<\/p>","protected":false},"excerpt":{"rendered":"

The main features of Q345qE bridge steel plate are high strength and good toughness. The welded joint has high strength and good toughness and can meet the performance requirements of the bridge structure for the weld seam. in general<\/p>","protected":false},"author":1,"featured_media":2660,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[27],"tags":[2323,771,1610,2322,943],"class_list":["post-2659","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-rivet-welding","tag-bridge-engineering","tag-corrosion-resistance","tag-high-strength-steel","tag-q345qe-bridge-steel-plate","tag-welding-performance"],"_links":{"self":[{"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/posts\/2659","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/comments?post=2659"}],"version-history":[{"count":0,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/posts\/2659\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/media\/2660"}],"wp:attachment":[{"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/media?parent=2659"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/categories?post=2659"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/endlfh.com\/fi\/wp-json\/wp\/v2\/tags?post=2659"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}