Case Study VI Design and Development of Angle Valve With expanded outlet for flashing fluid

RK Control Instruments Pvt Ltd > Products > Case Study VI Design and Development of Angle Valve With expanded outlet for flashing fluid
case study image VI

Problem / challenges Faced  

  • The process parameter causes high flashing and pipe configuration requires angle valve. The inlet pressure is 80 bar and outlet pressure are about 2 bar at 235 Deg C temperature, the vapour pressure is 60 bar for the fluid at this temperature and causes high flashing during pressure reduction.

Operating Parameters / Specifications

  • Inlet Pressure: 80 bar
  • Outlet Pressure: 2 bar
  • Flow rate 9500 kg/hr
  • Working Temperature: 235Deg C
  • Fluid: MEOH + SODIUM METHOXIDE + FATTY ACID 
  • Vapour pressure of fluid at working Temperature: 60 bar
  • CV-18
  • Valve Size- Inlet: 4” & outlet: 8” 
  • Rating: 900#
  • End connection: Butt Weld
  • Actuator: Diaphragm actuator

Design Solution: 

While sizing and selection, it shows that the control valve will work under high flashing service. 

Due to the transformation of fluid from liquid to gaseous form, there is a high volumetric expansion. For accommodating this high volumetric expansion and to reduce the fluid velocity at outlet, RKCIPL recommended to change the outlet pipe size to 8”. The control valve  selected was flow over the plug (Flow to close) configuration, to ensure that the fluid after pressure reduction is moving away from trim.

Also, RKCIPL recommended to use ASTM A 217 WC6 body material, due to high flashing against customer’s initial requirement of ASTM A 216 WCC.

The angle valve offered has HFD trim design (two cages) with Seat diffuser and a baffle plate at outlet to ensure that last stage pressure reduction will have minimum impact on trim erosion.

Due to high flashing, the cage, plug and seat are provided with full stellite to increase trim life.

A detailed CFD analysis on our software confirmed that the acceptable Cv value is achievable, based on the fluid properties.

Benefit –  

Longer trim life and easy maintenance due to clamped seat design.


Economics: Was about 30 % Lower than Customised solution offered by Indian competitor.