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believes 3-D printing can transform turbine

manufacturing and recently opened its

Finspang factory to showcase its progress.

Incremental improvements in gas

turbine performance are becoming harder

and harder to achieve, but technological

advances have opened up the potential for

large gains in turbine production.

Siemens is investing millions of dollars

in 3-D printing, or additive manufacturing

(AM), as it is often called in an industrial


In August Siemens added to its AM

portfolio with the acquisition of an 85%

stake in Materials Solutions Ltd., a U.K.

company that pioneered the use of

Selective Laser Melting (SLM), which is

used to melt or “weld” powdered metal

compounds used in additive manufacturing.

Siemens began using AM for plastics in

1989 and began using it in power

generation in 2009. The company now has

three facilities for additive manufacturing,

the newly acquired facility in Britain, a site

in Berlin for large gas turbines, and its

largest AM site, in Finspang.

Finspang is a town of about 12,400

inhabitants roughly 92 miles (147

kilometers) southwest of Stockholm. It

would seem to be in the middle of nowhere,

but it has a history of turbine

manufacturing dating back to 1913. So

when Siemens acquired it in 2003, it

already had the tool shops and other

infrastructure needed for heavy


Finspang is where Siemens

manufactures five of the 18 turbines in its

portfolio, including its best selling SGT-800

turbine, which ranges in capacity from 48

MW to 54 MW, and packages another three

turbines. In all, nearly half of the company’s

gas turbine fleet passes through Finspang.

Finspang is also on the leading edge of

Siemens’ AM efforts with capabilities that

run from design and development to

manufacturing and testing. The company

has been using AM in Finspang since 2009

and shipping turbines with AM components

from Finspang since 2013.


The Finspang facility produces three

AM products for Siemens. The company

uses AM to make a fuel swirler for its SGT-

750, its newest gas turbine.

The swirler is a small cylinder about

one-and-a-half inches in diameter that is

hollow and fluted. It mixes fuel and air and

was designed specifically for the SGT-750.

All seven SGT-750s that have been shipped

have swirlers made using AM.

Other turbines have swirlers, but not of

the complexity of the one in the SGT-750.

That could only be done using AM, says

Vladimir Navrotsky, chief technology

officer in Siemens’ distributed generation

service division.

Siemens also uses AM to manufacture

a small clip that is used to control the

amount of cooling air going into the turbine

blade. The goal is to have AM produced

clips in all of the SGT-800 turbines. AM

chips have been in serial production since

2015, and Siemens uses AM to repair and

replace burner tips on burners that go into

turbines. In the past, the tip was cut off

along with some of the body of the burner

and a new tip was welded in place. Using

AM, the company is able to cut off the

burner tip closer to where it meets the

body of the burner. The body of the burner

is then put in the 3-D printer and the new

burner tip is built in place. Siemens is using

AM to repair burner tips for both its SGT-

700 and SGT-800 turbines and says AM can

do the job about 60% faster than is possible

using conventional methods.

But Siemens is looking to get the most

value out of AM by expanding it to larger

components, such as the entire burner. The

burner is a critical component of a gas

turbine. It sits between the compressor

blades and the turbine combustor blades

where it mixes air and gas and burns the

fuel at temperatures up to 1,500 degrees


A burner for a SGT-700 or a SGT-800 is

about 700 millimeters long and weighs as

much as 20 kilograms. It includes flanges

or vanes for mixing air into the fuel mix, as

well as nozzles for fuel and, at the end of

the unit, the burner tip.

AM also eliminates the welding needed

to put together the parts of a conventional

burner. Siemens says AM will enable it to

use up to 63% less material and to design

some elements into the burner tip rather

than add them on at a later stage. For

instance, conventional burners require

external tubing for fuel. With AM, the

tubing is incorporated into the design and

runs inside the walls of the combustors like


AM also allows flexibility in the design

of the burner tips. Different types of lattices

can be manufactured into the fuel nozzles

of the burner tips. Different lattice patterns

allow the burners to burn different fuel

mixes, such as biomass or natural gas

mixed with other reactive fuels or with

hydrogen. Siemens says the wider array of

fuel mixes opens the potential for turbines

to operate with lower emission levels.

In early September, during a tour of the

Finspang facility, Thorbjoern Fors, CEO of

distributed generation service in Siemens’

power generation services division, said the

new fully printed burners would be “ready

in weeks.”

Next on the horizon for Siemens is the

3-D printing of turbine blades. Like

burners, turbine blades live in a harsh

environment with high temperatures, but

are also subjected to high centrifugal forces

and velocities that can reach the speed of


At present the AM materials are not

sufficiently developed to handle 3-D

printing of turbine blades, Novrotsky says,

but Siemens is using AM for rapid

prototyping of blades and eventually hopes

to use AM for the commercial production

of blades.

Using AM for turbine blades could reap

even more benefits. Engineering better

built-in cooling features into the design and

manufacture of the blades and making the




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