欧美午夜福利影院在线免费观看|中文字幕一区二区三区三州|国内精品一区二区三区久久|一区二区三区字幕在线观看

raw materials and finished steel structure approach

Guangzhou Steel tells you: raw materials and finished steel structure approach

(1) Guangzhou Steel Engineering steel materials used should be consistent with the design documents and the relevant existing standards, and have quality certification document, the admission after passing inspection before using.
(2) site acceptance steel, in addition to compliance with "Steel construction norms" gb50755-2012, there should be consistent with existing national standards "Steel Construction Quality Acceptance" gb50205-2001 of. Belonging to one of the following steel, should be carried out in full retest sampling:
① foreign steel imports;
② mixed batch of steel;
③ thickness equal to or greater than 40mm, and the design of the performance requirements z slab;
④ safety rating for a building structure, large span steel structure, the main force of the steel components used;
⑤ steel retest design requirements;
⑥ doubt on the quality of steel.
(3) the requirements of the steel sheet in the thickness direction, z15 grade steel for each inspection lot by the same brand, the same heat, the same thickness, the same delivery shaped steel plates, each batch weighing not more than 25t; z25, z35 grade steel sheet by sheet reinspection.
Standards (4) steel imports reinspection sampling, sample preparation and test methods shall design documents and contract execution. Customs inspection results should be approved by the supervising engineer, later recognized as an effective material retest results.
Welding materials (5) for important welds, or welding material quality certificate document is doubt, should be sampled retest, retest when the wire should press five batches (quite furnace batch) to take a series of tests, the electrode It should be in three batches (quite furnace batch) to take a series of tests.
(6) ordinary bolts as a permanent attachment bolts, when the design document or its quality is doubtful, should be a minimum tensile load bolt physical reinspection, when reinspection each size bolt checks 8.
(7) High strength large hexagon head bolts connecting deputy and torsional shear bolts connecting deputy should each have a torque coefficient and tight coaxial force (Pretension) factory qualified inspection reports, and comes with the box. When the bolts connecting deputy storage time more than six months after use, the relevant requirements should be re-torque coefficient or fastening shaft force test, qualified before use.
(8) high-intensity large hexagonal bolts connecting deputy and torsional shear bolts connecting deputy should individually tightening torque and axial force coefficient (Pretension) reinspection, the test bolt construction bolt batch should be installed on-site at random, 8 sets of connections made each batch extraction retest.