Saturday, 7 March 2015

HMCS IROQUOIS engine room (Updated & Expanded)

As my first blog post ever, this will probably be slightly unpolished, as I see how this all works.

The heart of HMCS IROQUOIS: her engine room is home to four propulsion gas turbines, producing between 12,788 shaft horsepower (cruise) and 51,000 shaft horsepower (main), along with various other equipment.

The port main (boost) turbine enclosure (left) and the local controls for all propulsion gas turbines (right, see below for better photo). I never did figure out what the Tabasco sauce was for.
The starboard Allison cruise turbine within its enclosure. The compressor stages are to the left, while the turbine is to the right.
The propulsion gas turbines are mounted backwards (compared to an airplane), with the compressor intakes pointed aft (left in the photo) and the turbine and exhaust pointed toward the bow (to the right). The shaft to the gearbox comes off the compressor end of the engine.

Starboard cruise turbine enclosure with insulation on the exhaust seen at the forward end.

Looking aft at the exhaust ducting from the starboard cruise turbine.

The starboard MAAG gearbox. Each of the green inspection ports covers a transparent window displaying part of the gearbox interior.

Each gearbox accepts two shafts on the forward end - one from each of the cruise and boost turbines. 

The aft end of the starboard gearbox (to the right of the photo) connects to the starboard propeller shaft, which I will cover in a subsequent post. 

Port gearbox. Note that the inspection ports are painted red (port) and green (starboard) to help identify which gearbox is which.
Looking forward from behind the starboard gearbox. Protective wire mesh at the bottom of the photo is probably covering where the propeller shaft exits the gearbox.
Although all the various bits of machinery onboard IROQUOIS and her sisters are controlled from the MCR (Machinery Control Room), there are also local controls mounted in the engine room, seen here (and seen to the right of the image at the top of this post).

The local control panel for the four propulsion gas turbines is located between the two main (boost) gas turbines. This panel is generally manned whenever the engines are started, and can provide local control if contact with the MCR is lost.
 This panel provides direct control to all four propulsion turbines, and the diagrams and layout on this panel show the basic machinery arrangement - the cruise turbines are located outboard toward the hull on the port and starboard sides, and the boost turbines are located inboard on either side of the ship's centreline. This panel allows local control of not only the gas turbines, but also the two gearboxes (the long rectangles on the lower half) as well as the equipment that controls the pitch of IROQUOIS' controllable pitch propellers.

Cruise turbines are intended to propel the ship economically, typically at speeds of up to 20 knots or so (I'm guessing, I don't have the exact figure in front of me), while the main (boost) turbines are used to propel the ship up to its published maximum speed of 29 knots and possibly beyond. The basic arrangement of the gas turbines and gearbox is very similar to the Y100 steam turbine powerplant arrangement as designed for the ST. LAURENT class of destroyer escort in the 1950s, which I have written about elsewhere.

The ship's power generating equipment is located in the Auxiliary Machinery Room (AMR), immediately aft of the Engine Room. 

IROQUOIS will pay off this spring, just shy of 43 years after she was commissioned into the Royal Canadian Navy.

1 comment:

  1. Thank you Sandy for this interesting article and good luck with your new blog. Blogging can be a lot of fun. Cheers Roger