Tank loading couplings

Railcar couplings

The railcar coupling is an integral crossover mounted onto rail tanks or road tankers in order to allow quick and safe connection to loading arms or other terminal facilities.


Process and Design

The connection is a wing union fig. 602.railcar coupling


1 - The spherical tapered male plug provides metal-to-metal secondary sealing.

2 - ACME or ISO union thread.

3 - Forged wing union nut.

4- The primary seal element can be supplied in different materials to suit fluid service (FKM or EPDM).

5 - A chain retains the nut whilst the coupling is connected with loading arm.

6 - Raised face flange with position indicator.

railcar couplings

railcar couplings


Safety Alert

Always use a brass hammer in order to avoid sparkling whilst striking the wing union nut, in particular when operating in hazardous areas. Always use an original FCE wing union. The use of a copy may seriously affect the safety of the operation.



Loading and unloading of various liquid and gaseous fluids (hydrocarbons, refined products, chemicals, LPG, NH3, etc.).


Size & Rating:

Wing union size : 2'' and 3" figure 602 (ACME & ISO thread).railcar coupling

Flange size: 2" (DN50) and 3" (DN80).

Flange rating: ISO PN40 raised face.

Pressure rating: 30 bars.

Pressure test: 45 bars.

Working temperature: -46°C to 80°C.


Carbon steel A350 LF2.



  • 1/4" sampling point with special ball valve.
  • Perforated nut for closure with standard pin-wrench instead of hammer.



  • ASME B31.3
  • PED 2014/68/EU Article 4.3
  • NF EN12561-3 & AC T81-110
  • Hydrostatic Pressure Test
  • Quality book and Operating & Maintenance manual



The use of a 3 part body on the ball valve is innovative with a number of advantages from a safety & operational viewpoint. One flange of the valve is welded to the line thus alleviating effects of vibration or corrosion on a threaded connection.


Valve body repair & internal seal replacement can easily be carried out “in situ”.

There is, due to the construction, a much lower risk of the valve being removed or lost. Also, the valve is always correctly orientated.


The installation of the valve encourages regular maintenance to guarantee safe operation by having repair kits on hand rather than replacing by a threaded valve.

Sans titre

railcar couplings