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Wood Railway Sleeper refers to the sleeper made of wood. Also known as sleepers. To make Wood Railway Sleepers, tough and elastic wood should be used. Wood Railway Sleepers can be divided into ordinary Wood Railway Sleepers, turnout sleepers and Bridge sleepers according to their uses. The standard length of ordinary Wood Railway Sleeper is 2.5m, and its section shape is divided into two categories, I and II, which are used for different grades of lines.
Brief introduction
Since the invention of railway, Wood Railway Sleeper is still widely used. In the early days of the invention of railway, due to the low level of economic development and technical level at that time, but rich in wood resources, Wood Railway Sleepers were used in the railway. So far, in North American national railway, Wood Railway Sleepers are still mainly used. Due to some disadvantages of Wood Railway Sleepers, such as: perishable, poor track stability, uneven elasticity, etc., Wood Railway Sleepers are basically not used in high-speed railway.

The commonly used woods are Korean pine, larch, masson pine, spruce and fir in hardwood sleepers. 
Specification size
According to experience, the length of Wood Railway Sleepers is generally 1.7-1.8 times of the standard gauge, and the length of Wood Railway Sleepers used for the standard gauge in China is 2.5m.
Ordinary Wood Railway Sleeper: the standard length is 2.5m, and its section shape is divided into I and II categories. Class I: width 22cm, thickness 16cm; class II: width 20cm, thickness 14.5cm; used for different grades of lines.
Turnout Wood Railway Sleeper: used for Wood Railway Sleeper on turnout. There are two standards for section size:
The 75 type standard is: width 22cm, thickness 16cm; length from 260cm to 485cm, each length difference 15cm, a total of 16 length specifications.
Type 92 standard is: width 24cm, thickness 16cm; length from 260cm to 480cm, each length difference 20cm, a total of 12 length specifications.
It is selected in groups according to the actual width of the turnout.
Bridge Wood Railway Sleepers: Wood Railway Sleepers used on bridges. The cross-section size varies with the center distance of the main beam (or longitudinal beam).