BS EN ISO 17639 2013 Destructive tests on welds in metallic materials. Macroscopic and microscopic examination of welds.pdf PDF 894.48KB 18页 BS EN 12390-8 2019 Testing hardened concrete. Depth of penetration of water under pressure.pdf PDF 579.14KB 12页 BS EN 1514-1-1997 法兰盘及其连接件有PN标识的法兰盘用密封件的尺寸第1部分.pdf PDF 314.4KB 22页