Construction of the penstocks at the Krasnoyarsk hydroelectric station

Conclusions

• 1. Penstocks intended for operation at temperatures below −40°C must be designed and manufactured from low-alloy construction, heat-treated steel of the 09G2S grade.

• 2. The advisability of using manual or automatic welding under a layer of flux or electric slag welding is decided by engineering economic analysis of the efficiency of using one or the other form of welding, depending on the parameters of the pipeline members, the length of continuous joints, type of joints, and the design of the installation.

• 3. On large volume erection projects carried out on large-scale pipeline construction, it is advisable to set up special plants fitted with 50-ton gantry cranes, in addition to fixed roller trains. In conditions where the automatic welding plants do not have gantry cranes, general-purpose roller trains must be used for automatic welding.

• 4. Application of the “suspended assembly” method for the pipeline members has enabled erection work to be carried out at accelerated rates, irrespective of the condition of the construction, erecting the concrete blocks, dispensing with offsetting the blocks under the pipeline members, thus simplifying the shuttering work and lowering the cost of building and erection.