Revamp for Two Ammonia Train Turbines - Delaval

Project Description

One of our North American customers has two identical Delaval steam turbines to drive an ammonia compressor train for their 1100 tons/day ammonia production plants. The customer was eagerly looking for ways to improve their rated power, efficiency & reliability.


Siemens Energy recommended the customer to do a steam path revamp. Our proven solution increased the Delaval turbine's rated power from 13,095 HP to 17,000 HP, along with a 6-7% efficiency improvement. The improved steam path utilizes optimized airfoil designs, improved seals, and a fine-tuned aerodynamic match of stationary to rotating airfoils. Additionally, improvements to the mechanical components such as bearings, seals, and valve operating gear parts lead to improved reliability as, the customer wanted. Our solution has been sucessfully implemented at the customer site. 

Customer Value

The increased rated power of ~4,000 HP helps the customer to expand their production. The 6-7% efficiency gains help the customer reduce fuel costs and lower steam consumption. Additionally, recovery of aging losses will have further steam consumption savings. Improved mechanical reliability helps keep the train online by reducing the number of forced shutdowns.. 

Delaval Ammonia Turbine Design Rating - After Revamp

Exhaust Pressure
545 PSIG / 610°F
4” HgA 
17,000 HP
7,035 Rated RPM

Performance Comparison - Before & After Revamp

Original Steam Flow @ 13,095 HP
Adjusted Steam Flow for aging loss (est’d) 13,095 HP 
Revamp Steam Path @ orig 13,095 HP
Revamp Steam Path @ 17,000 HP
116,000 Lb/hr
124,000 Lb/hr
109,000 Lb/hr
140,600 Lb/hr
8.86 Lb/HP-Hr
9.47 Lb/HP-Hr
8.32 Lb/HP-Hr
8.27 Lb/HP- Hr