Like our other assets such as trains and track, we have a continual programme of maintenance and renewal for our lifts and escalators.
Keeping escalators and lifts in top condition helps ensure the safety and accessibility of our network.
Our escalators are heavy-duty machines that carry millions of people each year. They must be refurbished every 20 years and replaced every 40 years.
Our lifts get a routine maintenance check every two weeks, a full MOT every six months and a partial refurbishment every five years. Lifts must be fully replaced every 10 to 20 years, depending on the type.
New escalators are modular, not bespoke, which makes them easier to refurbish and replace. We're using new traction lifts which offer reduced journey times and are more energy efficient.
Over its 40-year lifespan, an escalator will travel the equivalent distance of a trip to the moon and back. Keeping escalators in top condition helps ensure your safety and your ability to access our network.
Due to the nature of the work, replacement and refurbishment can take a number of months to complete.
"It can take up to 24 weeks to carry out an overhaul, particularly when spare parts have to be manufactured from scratch and installed deep underground in confined spaces. Physical and geological considerations mean that every escalator on the Underground network is custom-built for its location. Many components are made bespoke by the manufacturers, which mean a stockpile of spare parts can't be built up."
LU Capital Programmes Director
Why escalator and lift work takes time
Did you know that the escalators in shopping centres, supermarkets and department stores are different from the escalators you use on the Tube network?
They are generally used by customers during opening hours only.
Because of this, they are built to cope with lower passenger loadings compared to a public transport escalator.
Escalators and lifts on the Tube network are used by far more customers - 1.265 billion a year.
They tend to be in operation in both directions for a period of up to 20 hours a day, 7 days a week, 364 days a year.
The machinery required to operate these escalators and lifts is therefore classed as heavy engineering machinery. It allows for reliable regular use by customers
Escalator and lift replacement and refurbishment can be a lengthy process. This is due to the size and
difficulty of the task:
Escalators are heavy-duty machines, custom built for each station
Parts have to be manufactured from scratch and installed deep underground in confined spaces
The escalator parts can only be delivered in the short Engineering hours slot, because of their size. If they were to be delivered during operating hours, they would end up being in the way of customers and compromising off-loading restrictions on the size of these deliveries via road in London
Old escalators have often supported other structures which need to be carefully managed during replacement and refurbishment works
A typical heavy-duty escalator weighs 40 tonnes and has a vertical rise
of 15 metres. If laid flat, it would be over 37 metres long
Typically, there are six to seven (maximum 20) people working on an escalator on each shift, two shifts per day, six or seven days per week
For a typical 15-metre rise escalator, there are approximately 15,000 moving parts
In some stations, the escalators were installed before the Second World War and actually form part of the station structure. This was the case at Embankment, where considerable structural modernisation was required to create enough space to fit a new escalator. New, custom-built machines ensure a reliable escalator service for many decades to come
All Tube escalators have full communication, fire detection and suppression systems which are required to be tested and declared operational before they can be used by the public
Lift replacement work often takes place deep underground, in cramped lift shafts
Due to the nature of the work it can take a number of months to complete. We're always looking at ways to reduce disruption to customers while we undertake lift and escalator refurbishment and replacement. For example, we will sometimes replace more than one lift at a time to reduce the overall time they are unavailable.
Our lifts and escalators run 20 hours, and sometimes 24 hours, a day in support of work at stations in traffic hours
There are 440 passenger escalators and 184 passenger lifts across the Tube network
Our busiest lifts at stations such as Covent Garden will carry up to 80,000 people a day through the station
Over its 40-year lifespan, an escalator will travel the equivalent distance of a trip to the moon and back
Our lifts can hold up to 50 people and travel up to four metres per second
Our escalators travel up to 0.75 metres per second, faster than the 0.5 metres per second in escalators used in shops and department stores
Landing lengths on our escalators are longer than those in department stores to allow for the high speed at which our escalators operate
Waterloo has the most escalators of any station with 23
The longest escalator - 60 metres - is at Angel. The shortest is at Stratford - just 4.1 metres
The deepest lift shaft is at Hampstead - 55.2 metres. The shortest is at King's Cross St. Pancras - 2.3 metres.
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