Railway coupler is used for connecting locomotives and vehicles or vehicles and vehicles,transferring traction and impact,and maintaining a certain distance between the vehicles.According to the opening ways it can classify top operating and bottom operating.Opening the coupler by the lifting mechanism above the coupler head is called top operating (General wagons adopt ), Opening the coupler by the ejector lever action down the coupler head is called bottom operating(Passenger trains adopt).

Coupler consists of three parts head , shank and tail. The thick section is called coupler head in front of the coupler.The coupler head is equipped with knuckles,knuckle pivot pins,knucklelocks,knuckle throwers and lock-lift pins.Coupler rear is called coupler tail. The couplers tail have keyhole,in order to connect with the yokes

》Coupler
The coupler is used to the connection between the locomotive and the vehicle or between the vehicle and the vehicle, to transmit the traction and impact forces, and to maintain a certain distance between the vehicles. The coupler is divided into an upper top unlock type and a bottom unlock type according to the opening manner. The top unlock type is adopted by the lifting mechanism of the upper part of the hook of coupler (the general wagon adopts this type); the bottom unlock type (the passenger car adopts) is realized by the action of pushing the top lever of the lower part of the coupler hook head.

Standard：AAR M-201 Grade E/E+ TB/T 3212 Grade C/E
Standard：AAR M-211/205 TB/T 456


》Knuckle
The knuckle is a key component of the coupler. When the couplers are interconnected, it is usually necessary to rotate or move the knuckle to achieve the locking and unlocking. The knuckle is generally made of casting. In recent years, due to the improvement of the manufacturing level, the knuckle made of forging has appeared, and the quality is much higher than the traditional casting knuckle.
Material：AAR M-201 Grade E/E+ TB/T 3212 Grade C/E
Standard：AAR M-211/205 TB/T 456

》Yoke
The yoke is usually installed inside the center sill of the car body. The yoke is used to place the draft gear(buffer), and then the yoke and the draft key are connected to the shank of the coupler, which is an important connecting component in the draft gear system. The yoke is usually matched according to the different draft gear(buffer) outer dimensions, and it is also necessary to maintain compatibility with the coupler. The yoke is generally made by casting and forging.
Material：AAR M-201 Grade E/E+ TB/T 3212 Grade C/E
Standard：AAR M-211/205 TB/T 456


》Draft Gear
It is used to alleviate the longitudinal impact and vibration caused by the change of the traction force of the train during the running of the train or the collision of the vehicles during the starting, braking and shunting operations. The draft gear has the function of dissipating shock and vibration between the vehicles, thereby mitigating the damage to the structure of the vehicle carbody and the loading of the cargo. The working principle of the draft gear is to relax the impact force by means of the compression elastic element, and absorb the impact energy by friction and damping during the deformation of the elastic element.

Types
According to the structural characteristics and working principle of the draft gear, could be divided into: friction draft gear, rubber draft gear and hydraulic draft gear.
Standard：AAR M-901 TB/T 1961

Performance Parameter of Cement-Spring Draft Gear	Value
Rating Capacity(KJ)	80
Rating Impact Speed（km/h）	10
Rating Resistance Force（kN）	2450
Rating Travel Distance（mm）	83
Absorption Rate（%）	≥90
Free Length（mm）	577
Length when assembled on a vehicle（mm）	568
Operating Environment	-50℃-50℃

   

》Striker/Coupler Guide
It is usually installed at the end of the carbody (center sill) for placing and fixing the coupler. It is also an important part for connecting the coupler and the carbody. Generally different types of couplers need to match different coupler strikers. Coupler striker is generally made by casting.
Material：AAR M-201 Grade C/E/E+ TB/T 456 Grade C/E/E+
Standard：AAR M-211/205

Name：lifter E6A
Material：AAR M-201 Grade B-casting steel
                ASTM grade 65-45-12 ductile iron
Specification：S-105
Suitable：AAR type E/EF
Weight：6.2 KG

Name：lifter E6A
Material：AAR M-201 Grade B-casting steel
                 ASTM grade 65-45-12 ductile iron
Specification：S-105
Suitable：AAR type E/EF
Weight：4.5 KG

Name：thrower E30A
Material：AAR M-201 Grade B-casting steel
                 AISI 1030  -forging steel
Specification：S-105
Suitable：AAR type E/EF
Weight：2.4 KG

Name：lock E40AE/42AE/42BE
Material：AAR M-201 Grade B-casting steel
Specification：S-105
Suitable：AAR type E/EF
Weight：5.5/5.8 /5.8 KG

Name：lifter F7
Material：AAR M-201 Grade B/C-casting steel
                 ASTM grade 65-45-12 ductile iron
Specification：S-116
Suitable：AAR type F/FR
Weight：1.8 KG


Name：rotor F8A
Material：AAR M-201 Grade B/C-casting steel
                 ASTM grade 65-45-12 ductile iron
Specification：S-116
Suitable：AAR type F/FR
Weight：1.5 KG

Name： rotor F10A
Material：AAR M-201 Grade B/C-casting steel
                 ASTM grade 65-45-12 ductile iron
Specification：S-116
Suitable：AAR type F/FR
Weight：1 KG

Name：rotor F9A
Material：AAR M-201 Grade B/C-casting steel
                 ASTM grade 65-45-12 ductile iron
Specification：S-116
Suitable：AAR type F/FR
Weight：1.8 KG

Name：thrower F31A
Material：AAR M-201 Grade B -casting steel
                 ASTM 1030-forging steel
Specification：S-116
Suitable：AAR type F/FR
Weight：1.8 KG

Name：lock F41A
Material：AAR M-201 Grade E -casting steel
Specification：S-116
Suitable：AAR type F/FR
Weight：1.8 KG

Name：lock F400
Material：AAR M-201 Grade E -casting steel
Specification：S-116
Suitable：AAR type F/FR
Weight：1.8 KG

》Follower Plate

Name：follower plate（fraont follower）
Material：AAR M-201 Grade E-casting steel
                AISI 1030- forging steel
Specification：AAR M 211
Suitable：AAR type FR
Weight：10 KG

》Draft key/Knuckle pin/Draft pin retainer（Keeper）

Name：draft key
Specification ：Meet AAR S-121
Material： AISI 1045

Name：draft key
Specification ：Meet AAR S-121
Material： AISI 1045

Name：draft key retainer keeper
Specification ：Meet AAR S-120
Material： AISI 1060