- If the average value of one lot dse not comply with the above requirement 1), compliance with above table shall be confirmed by testing double the number of bolts from the same manufacturing lot.
- If the sets does not comply with the above requirements 1) and, and, the manufacturing lot of the tested set shall not be used. In this case, each set of the failed lot shall be tested according to the requirement 1) and 2) before using.
e) Fastening
- Fastening work shall be carried out only when the temperature is between 0oC and 50oC.
- A single washer of the set shall be used in the nut side.
- Preliminary fastening of the bolt shall be carried out up to about 60% of its required axial force. However, in the preliminary fastening, the bolt tip shall be kept free from stress and not be used to prevent movement of the bolt when tightening the nut. After preliminary fastening, mark and then fasten until the bolt tip is fractured with a special fastening tool.
- Bolt shall be fastened from the inside to the outside of joint.
- One ninth drift pins and two ninths temporary bolts of all bolts shall be used when preliminary fastening.
f) Inspection at site
After finishing fastening, it is enough to confirm the following about all bolts on same day
- Bolts are completely fastened.
- Bolt, nut, washer isn’t spun both and reversed by marking.
- Bolt top is completely fractured.
g) Handling and storage of bolts
Attention shall be paid to the following points during handling and storage of bolts.
- In order to keep bolts in the same condition as when they left the factory, bolts shall remain in their original packaging until needed.
- Care shall be taken to keep the bolts free of rain, humidity, and dirt during storage.
- Only the necessary number of bolts for that day should be taken from the storage area. The bolt should be kept dry, free of dirt, and care should be taken not to damage the threads.
- Always confirm that the bolts being used are the proper type, length, and size for the splice.
- Make sure that washers and nuts are set properly and reverted or used upside down.
2.1.1.4. High strength hexagon bolts
a) Process of bolt fastening
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