Description
Step 1: Analysis
After the turbo has been received, the turbo is disassembled and analyzed. Then the parts
are thoroughly cleaned. The parts are then blasted.
Step 2: Surface treatment
The cast iron parts are blasted with a strong blasting grain. For the aluminum parts: a
A different blasting machine is used, which works with a ceramic glass bead. The lower
After blasting, housings are washed with the coarse blasting grain and also with ceramics
glass bead. The bearing housings are then ultrasonically cleaned to ensure that no explosions occur
sand or dirt remains. Finally, all parts are greased to prevent rust formation.
Step 3: Check
First of all, the turbine shaft is checked for straightness. A is used for this
Straightness meter bench with a dial indicator up to 1,0 micrometer. The
bearing locations of the turbine shaft and the bearing housing of the turbo are checked
using micrometers to check whether they are indeed within the permitted tolerances. The
compressor wheel is blasted with glass beads and checked for hairline cracks with metal
account. If all parts are technically in order, the balancing process can be started.
Step 4: Balancing
Balancing is one of the most important process steps when overhauling a turbo. The reason
because this is easy, as the speeds that a modern turbo can reach now exceed 220.000 rpm.
Any form of imbalance at these speeds will eventually or immediately lead to major damage
inside the turbo. For balancing turbos it is very important to balance the wheels dynamically.
This means balancing with two correction planes. Each component is balanced separately. After
all components are individually balanced, the rotor is mounted. This rotor too
dynamically balanced again. We use a Schenck balancing machine for this, see photo. The
parts must then be mounted in such a way that the turbo has become a rotating unit.
Since not all parts can be balanced individually, such as the thrust ring etc., the
the rotating part as a whole must be rebalanced using a VSR balancing machine.
For this we once again use a Schenck balancing machine, the Schenck 110MBRS VSR balancing
machine, the number 1 and is required and approved by all turbo manufacturers. This
The balancing step is carried out at the speeds that are also achieved on the engine. This is
an ideal final test before the overhauled turbo is mounted on the engine. When a turbo passes by
Step 5: Final adjustment
After balancing, the space on the bearings of the interior is then checked and this space is present
verified with the turbo manufacturer's data, after which the turbo is further phased
out. Finally, the actuator is adjusted to the factory value.
the last check, it's fine. In particular the high-precision balancing processes
make sure no detail is overlooked.
