IMU (Interurban Multiple Unit)

The IMUs were introduced to provide new rollingstock for the Gold Coast line in 1996. The IMUs are a long-distance optimised version of the SMUs, with extra features such as larger seats, luggage racks, toilets[2]. On the exterior, they are similar enough that Queensland Rail uses identical photos for them on their "Carriage Layouts" section. Another difference is the IMU100 and 120's higher top speeds than their SMU counterparts. I think it is due to a better cooling system for one of the parts (traction motors?), but I can't seem to find the place where I read it again. They also have a higher gear ratio of 1:4.367 vs 1:5.169 on the SMUs (not sure which variant tho, possibly the 100/200?)[4, 10].

Depots: Mayne, Robina, Nambour[11]
Common Lines Served: Gold Coast line, Airport line, Nambour and Gympie North line[11]

EDI/Bombardier Interurban Multiple Unit 100 series (IMU100)

The IMU100 as seen on QR's Carriage Layouts page

Timeline

  • 1993: A contract for four IMU100 units was awarded to Walkers Limited, Maryborough[2].
  • July 1995: As only four IMU100s were never adequate to service the line, a further six were ordered, numbered IMU105-110[2].
  • 1996: The first four IMU100s, IMU101-104, entered service before the opening of the new line[2].
  • 1997: IMU105-110 delivered[2].
  • March - November 2001: IMU100s upgraded to meet the new Disability Standards for Accessible Public Transport requirements based on the IMU120 design. This upgrade included, but was not limited to, the addition of six allocated spaces in the saloon of the DT Car because this car housed the wheelchair accessible toilet and it was not feasible for passengers to be expected to move from one end of the unit to the other. This was due to the aisle width between the transverse seats being of insufficient width to provide an effective accessible pathway[9].
  • 2017: IMU100s and SMU200s underwent an overhaul, including an upgrade of the traction package and Train Control Managment System on 10 IMU100s and 12 SMU200s, and one of the pneumatic cab doors of an IMU100 got upgraded. This work was done by Downer EDI Rail for $105,430,828[13].
  • December 2018: Downer secured a $80 million contract to refurbish the IMU100s along with the SMU200s at their Maryborough Service Delivery Centre. The upgrades included[8]:
    • An interior refresh – new floor coverings, refreshed handrails and grab handles and new seat foams and covers for enhanced customer experience.
    • An overhaul of key train subsystems to ensure the safety and reliability of the fleet.
    • New electrical systems (in partnership with ABB), including upgrade of onboard traction equipment and installation of a new Train Control Management System (TCMS).
  • January 17, 2020: QR paid out $2.6 million to CoachAir for "2019 IMU100 SMU200 HVAC Overhaul", possibly as part of Downer's refurbishment that started Dec 2018[12].
  • 2023: QR replaced the routers in EMUs, IMU100s, SMU200s, IMU120s, and SMU220s. The work was contracted out to Nomad Digital and cost $1.75 million[12].
  • 2023: Refurbishment of IMU100s and SMU200s was completed including the interiors, with the sole exception of IMU105, which still retains it's green ocean themed seat covers[8].
  • 2038: IMU100s anticipated to commence retirement (as of August 2021)[21].

Carriage Layout

Source

Carriage 1

Carriage 2

Carriage 3

EDI/Bombardier Interurban Multiple Unit 120 series (IMU120)

The IMU120 as seen on QR's Carriage Layouts page

In 1999, four IMU120 series units (121-124) were ordered for the Airtrain line to Brisbane Airport. They entered service in 2001 and feature high-backed seats with a head cushion as an extension to the SMU220-based seat design[2], as well as a top speed of 140km/h[14]. There is one toilet per unit and the luggage racks are in different configurations than the IMU100s due to interior design differences[2].

While the IMU100s and IMU120s can be used together to form 6-car sets, they no longer do so in revenue service due to electrical and mechanical differences[2]. The IMU120s are fitted with electric plug doors as opposed to air operated plug doors on the IMU100s, they are fitted with one A/C pod per car as opposed to two, and the cooling system has been changed to water cooling which eliminates the noise associated with the traction blower fans[14].

In order to keep the auxiliary converters and systems online through neutral sections of track, IMU120s and SMU220s automatically apply a small amount of regenerative braking while traversing sections at speeds above 20km/h. This reduces the need to rely on the battery system and is also the reason why they maintain full lighting and air conditioning compared to other units in the fleet. However, this can produce a nasty shudder through the train at speeds around 40-60km/h which is mostly unpreventable and varys depending on the unit[15].

Seating Capacity:
76 (IM5121–4: driving motor car); 80 (IM7121–4: trailer car); 59 (IM8121–4: driving motor car)[16]

Timeline

  • 1999: IMU121-124 ordered[2].
  • 2001 - 2002: IMU121-124 entered service[2].
  • 2021: Brake and pneumatic overhauls of SMU220s and IMU120s completed by Faiveley Transport Australia Ltd at a price of $5,735,919.34[13].
  • 2022: Coupler overhaul of SMU220s and IMU120s completed by Voith Turbo Pty Ltd at a price of $3,200,000, and compressor and air dryer overhauls completed by Knorr-Bremse Australia Pty Ltd at a price of $975,475.54[13].
  • 2023: Routers replaced in EMUs, IMU100s, SMU200s, IMU120s and SMU220s by Nomad Digital Pty Ltd for $1,756,757.72[12].
  • November 30, 2023: QR issued a tender for contractors to perform a Traction Package and TCMS Replacement on IMU120/160s and SMU220/260s (98x 3-car vehicles in total), stating that the existing Bombardier MITRAC traction package and Train Control Management System (TCMS) [known as TPT] equipment is becoming obsolete[17].
  • 2038: IMU120s anticipated to commence retirement (as of August 2021)[21].

Carriage Layout

Source

Carriage 1

Carriage 2

Carriage 3

Detailed Carriage Layout

Source archived here - see figure A2

Carriage 1

View full image

Carriage 2

View full image

Carriage 3

View full image

EDI/Bombardier Interurban Multiple Unit 160 series (IMU160)

The IMU160 as seen on QR's Carriage Layouts page

The IMU160 Series trains were ordered in 2005 when the Gold Coast line was being upgraded and duplicated, and were introduced in service from 2007 to 2011. The units are virtually identical to the TransPerth B series trains[19], which incorporate a European style Streamlined design, albeit with exposed Air-conditioning Pods[18]. They are also similar to the V/Line VLocity DMU, and Adelaide Metro 4000 class EMU trains with alterations to the headlights to complement with the rest of the Citytrain fleet[2].

They operate as three-car sets, with a driving motor car at each end and a trailer car in the middle. The trailer cars have pantographs but do not have motors[19] These trains are interoperable with the 260 series Suburban Multiple Units as they have almost identical specifications[2].

In 2007, it was discovered during a "1200-point check" that the air conditioning units on top of the carriages had been built 10mm too wide for the loading gauge, sparking concerns over tunnel clearance in a 4m section between Central and Fortitude Valley stations[20].

IMU160s are anticipated to commence retirement in 2049 (as of August 2021)[21].

Seating Capacity:
66 (IM5161–88: driving motor car); 84 (IM7161–88: trailer car); 65 (IM8161–88: driving motor car)[19].

Carriage Layout

Source

Carriage 1

Carriage 2

Carriage 3

IMU160 Virtual Tour

See: https://www.queenslandrail.com.au/Customers/Accessibility/Site%20Assets/Virtual%20Tours/IMU.html

Sources