KB TIE PLATE PER GOST | Railway Fasteners

The KB tie plate (rail baseplate) per GOST standards is a specialized steel component used for the separate fastening of rails (typically R-65 or R-50) to reinforced concrete sleepers. Its technical requirements are defined by GOST 16277-2016 (replacing GOST 16277-93), which specifies the design, material properties, and manufacturing standards for "KB" and "KD" type plates. 

Standard Models and Applications

The KB series is primarily designed for heavy-duty and mainline tracks where separate fastening is required to maintain precise gauge and stability. 

• KB-65: Designed for R-65 rails. It is the most common model, featuring a double-shoulder design and four holes (two for rail clamping bolts and two for sleeper anchor bolts).

• KB-50: Designed for R-50 rails. It follows the same structural principles as the KB-65 but is sized for the smaller rail base of the P50 profile.

• KB-75: Used for ultra-heavy R-75 rails in specialized industrial or high-load environments. 

Material & Manufacturing Requirements

• According to GOST 16277, KB tie plates must be produced using specific steel grades and processes: 

• Steel Grades: Typically structural carbon steels like St3, St4, or St5. In China, it can be Q235,Q355,45# etc.

• Production Method: Manufactured through hot forged or casting (using cast steel or cast iron depending on the required load).

• Surface Quality: The rail seat must be tapered to provide the standard 1:20 cant (inward rotation) required for optimal wheel-rail contact. 

Assembly Components

In a GOST-compliant KB fastening system, the tie plate works in conjunction with specific hardware: 

• PC Rail Clamps (Клемма ПК): These are used with M22x75 T-bolts to secure the rail to the tie plate shoulders.

• Fasteners: A standard assembly includes the clamp, a bolt, an M22 nut, and a double-circle washer.