Bulgarian (BDS) Standards for Steel Materials

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Introduction to Bulgarian Steel Standards

The Bulgarian (BDS) standards for steel materials represent a comprehensive framework governing the classification and specification of various steel types used in industrial applications. These Bulgarian BDS standards steel materials provide essential guidelines for manufacturers, engineers, and quality control professionals working with different steel grades and compositions.

Covers:

• Group of standards for structural and constructional steels
• Group of standards for tool steels
• Group of standards for steels with special physical properties
• Group of standards for stainless and heat resisting steels

Comprehensive Coverage of Steel Categories

Structural and Constructional Steel Standards

The structural steel specifications within the BDS framework address the requirements for carbon, alloy, and structural steels used in construction and engineering applications. These standards ensure that materials meet specific performance criteria for load-bearing and structural applications.

Table 1. Group of standards for structural and constructional steels

Standard Number	Description
BDS 2592	Structural steels
BDS 3492	Unalloyed steel castings
BDS 4758	Concrete steel
BDS 4880	Low alloy steels
BDS 5785	Unalloyed high-grade steels
BDS 5930	Unalloyed boiler steels
BDS 6354	Alloyed constructional steels
BDS 6550	Alloyed steel castings
BDS 6609	High-temperature steels for boiler tubes
BDS 6742	Spring steels
BDS 6886	Free-cutting steels
BDS 7478	High-temperature steel castings
BDS 7933	Narrow gauge rails
BDS 9609	Cold rolled strip
BDS 9793	Rails
BDS 9801	Weldable steels for shipbuilding
BDS 10786	Rails of vacuum-treated steels
BDS 10787	Heat-treated rails
BDS 11488	Cold-rolled sheet for cold-drawing
BDS 12731	Seamless tubes for ball and roller bearings
BDS 14351	Hot rolled sheet for cold-drawing
BDS 15888	Structural steels resistant to weathering
BDS 5084	Welding filler rod
BDS 14679	Wire for built-up welding

Tool Steel Classifications and Requirements

Tool steel classifications under the BDS system provide detailed specifications for steels designed for manufacturing tools, dies, and precision instruments. These standards address the unique hardness, wear resistance, and durability requirements essential for tool applications.

Table 2. Group of standards for tool steels

Standard Number	Description
BDS 6751	Carbon tool steels
BDS 7008	High-speed steels
BDS 7938	Alloyed tool steels

Special Physical Properties Steel Standards

Steels with special physical properties require specific standards to address their unique characteristics. This category includes electrical quality steels and materials designed for specialized industrial applications where standard steel properties may not suffice.

Table 3. Group of standards for steels with special physical properties

Standard Number	Description
BDS 10112	Electrical quality steel

Stainless and Heat-Resistant Steel Specifications

Stainless steel standards within the BDS framework cover corrosion-resistant and high-temperature applications. These specifications ensure that materials can withstand harsh environmental conditions while maintaining their structural integrity and performance characteristics.

Table 4. Group of standards for stainless and heat resisting steels

Standard Number	Description
BDS 6738	Stainless steels
BDS 9631	Stainless steel castings
BDS 9634	Valve steels
BDS 5084	Filler rod
BDS 14679	Rod for built-up welding

Standard Documentation Structure

Each BDS standard provides comprehensive technical information including standard numbers and publication years, specific grade designations, detailed chemical composition requirements, and critical steel mechanical properties such as yield point, tensile strength, and notch toughness values. When applicable, additional specifications include steel type classifications, manufacturing methods, plate thickness requirements, heat treatment procedures, and other relevant technical data.

Manufacturing and Quality Specifications

The standards address various manufacturing aspects including hot-rolled plates, sheets, and strips specifications. Free-cutting steel requirements are detailed to ensure optimal machinability characteristics. High-temperature steel castings standards provide guidelines for applications requiring elevated temperature performance.

Welding and Fabrication Standards

Welding filler rod specifications ensure compatibility and performance in joining operations. These standards address chemical composition, mechanical properties, and application-specific requirements for various welding processes and base material combinations.

Technical Data and Properties

The Bulgarian BDS standards steel materials documentation provides extensive technical data for each steel category. Yield point specifications ensure materials meet minimum strength requirements under load. Tensile strength values define the maximum stress materials can withstand before failure. Notch toughness measurements indicate material resistance to crack propagation under impact conditions.

Application-Specific Requirements

Pressure vessel plate standards address the stringent requirements for materials used in high-pressure applications. These specifications ensure safety and reliability in critical industrial processes. Electrical quality steel standards provide guidelines for materials used in electrical equipment and magnetic applications.

Standard Organization and Accessibility

The four-volume organization of BDS steel standards ensures comprehensive coverage while maintaining accessibility for users seeking specific information. Each volume contains formally approved classifications, practical guides, detailed specifications, standardized test methods, and technical terminology relevant to specific steel categories.

Quality Control and Testing Methods

Standardized test methods within the BDS framework ensure consistent evaluation of steel mechanical properties and chemical composition. These testing procedures provide reliable means for verifying compliance with specified requirements and maintaining quality control throughout the manufacturing process.

Heat Treatment and Processing Guidelines

Heat treatment specifications within the standards ensure optimal material properties for specific applications. These guidelines address temperature ranges, cooling rates, and processing parameters necessary to achieve desired mechanical properties and microstructural characteristics.

Conclusion

The Bulgarian (BDS) standards for steel materials provide a comprehensive framework for specifying, manufacturing, and testing various steel types. These structural steel specifications, tool steel classifications, and stainless steel standards ensure consistent quality and performance across diverse industrial applications. The detailed documentation of steel mechanical properties and chemical compositions enables engineers and manufacturers to select appropriate materials for specific applications while maintaining compliance with established quality standards.

The systematic organization of these standards into four distinct categories facilitates easy reference and application in industrial settings. By providing detailed technical specifications, testing methods, and quality requirements, the BDS standards contribute significantly to the reliability and safety of steel applications in Bulgarian industry and beyond.