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Papers deals with the problems of repairs at new and also already loaded components of steam and gas turbines. Generally, it is about welding repairs at valve and turbine chambers, transmitters, vane carriers, tripping valve body and so on. There are both technological defects caused by casting (e.g. shrinkage cavities, misruns, porosity and cracks) and defects caused by operation (thermal-stress fatigue, incorrect method of operation, etc.). Many of the mentioned defects take effect not until the final technological method - mostly at machining. However, in this production phase it is not possible to get form the supplier new production elements due to economical and also delivery time reasons. All of that results in delay of production and penalty. As the major aim of this paper, there was to find such repairs techniques which can ensure serviceability of mentioned devices under the standard regime. In these cases is needed to use much lower tempering temperature than under the standard production, mainly because of necessity to eliminate deformation caused by heating of part that is not possible to be subsequently removed by machining.

This paper discusses the factors that can lead to the degradation of masonry structures and provides an overview of the existing techniques for their rehabilitation and consolidation. The degradation of masonry is often related to negative actions of the environment, such as water penetration, freeze-thaw cycles, chemical attacks, and exposure to pollutants. These factors can lead to the appearance of cracks, scaling, erosion, and other types of deterioration of masonry. To preserve masonry structures, frequent monitoring and repairs (locally), preferably immediately after any degradation, are the most important measures. When degradation occurs, prompt action is necessary to prevent further deterioration and to apply appropriate rehabilitation and consolidation methods. Rehabilitating a construction involves replacing or restoring degraded elements to restore functionality to the pre-degradation level and to improve the overall performance of the structure. In contrast, consolidation focuses on strengthening an existing structure by adding new structural elements or by applying specific consolidation techniques with the aim of achieving increased structural capacity. These processes are often interconnected and part of a larger process of restoring or maintaining buildings or structures. Regarding traditional solutions for consolidating masonry elements and structures, these consist of repairing or rebuilding affected areas with classic materials, such as simple or reinforced mortars, welded meshes, dowels, steel bars and profiles. Traditional masonry repair works include filling cracks by injection, partial disassembly of walls followed by reconstruction, dismantling of mortar joints followed by deep filling, stitching of cracks with steel dowels, and reinforcing and facing with mesh or mortar. These techniques are applied according to the degree and type of degradation of the existing structure, as well as local and environmental conditions, with the aim of ensuring efficient and durable consolidation of the structure. The informed decision on the rehabilitation or consolidation solution used and how it is to be applied is usually made after extensive studies and consultations to achieve the best possible result. Generally, masonry structures are considered very resistant and durable, due to their history of over 6000 years. However, proper care and attention to detail are crucial to prevent degradation and to maintain masonry structures in good condition.

The main idea of this paper is to analyse the means for the rehabilitation of our cultural heritage timber structures. Several methods together with their application techniques are described, and also, the reasons for what these strengthening operations become imminent at a point. First of all, the necessity of the timber structural elements strengthening is explained through a short presentation of the factors which are degrading the material. Then, certain precautions and strengthening procedures are presented, all involving the usage of traditional materials like wood, metal, or concrete, and of modern materials like fiber reinforced polymeric composite.