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MEF express
MEF express (figure 2 and figure 3) is a bundle puller
entirely designed and manufactured by Maus Italia. The
hydraulic hooking of the tube plate makes it possible to
quickly insert and pull out the tube bundles when
refineries experience a shutdown with a consequent
work time reduction. The great solidity and sturdiness
of the structure as well as its innovative improvements
make this machine extremely reliable and safe. MEF
express is produced in different standard dimensions
according to the tube bundles weight, length and
diameter. A portable console enables to remotely
control all the operations with a consequent reduction
in the needed personnel and increase in final safety
margins. It is supplied with diesel or pneumatic
motorization and as well as motors for hazardous telescopic rotating column, allows the quick pulling/ Fig. 4 – MEF mobil
classified working area (Atex). inserting of the bundle. Once the truck is positioned, it
Maus Italia studied a special version of MEF express to is easy and quick to lift the extractor and to proceed
meet the need for the extraction of tube bundles on with the extraction.
petroleum platforms and installations at sea on large This system is particularly advised for the maintenance
vessels known as FPSO (Floating Production Storage companies which operate continuously in the
and Offloading). The machine is a MEF express Navy petrochemical plant field.
produced for this purpose following the highest
standards concerning shipbuilding. There are many
similarities with the on-shore MEF express as a rapid The problem of moving tube

extraction system. However, it is equipped with a bundles
special device that blocks any bundle oscillations due
to sea swell. It is very compact and light, suitable for Generally, during the lifting phase slings are used and if
handling in small spaces and powered by a mobile the distance from the OTL (Outside Tube Limit) to the
power unit. This machine is designed to work in force baffle diameter is small, the tubes easily bend and
10 sea conditions. consequently these break. If instead this distance is
high the baffle deformation is obtained.
MEF mobil For this reason in 2017 Maus Italia designed and
The MEF mobil tube bundle puller (figure 4) is designed patented the Bundle Tutor (figure 5). This machine
for areas difficult to access and is completely self- brilliantly solves the problem of grabbing and tube
sufficient, as it is presented as a global solution in bundles lifting during handling (production /
petrochemical plants for the extraction of tube bundles. maintenance), while operating in total safety and
This kind of puller operates autonomously without the eliminating the risk of damaging the baffles or
assistance of a crane for positioning and hoisting or crushing the tube bundle tubes. The independents
trucks for transport to the tube bundle maintenance adjustable cables of the Bundle Tutor ensures
area after extraction. It is solid, robust and stable and it compensation for any asymmetrical positioning
autonomously raises to a height of 4,2 m (166”), hence errors of the saddle bands located underneath the
enabling to approach the heat exchanger in a rapid and tube bundle. The bands and the central jaws ensure
precise way. perfect balancing of the bundle along its longitudinal
Furthermore, inserting the tube bundle after axis, preventing flections and deformations of the
maintenance becomes extremely rapid and precise tube ends caused by the weight of the projecting
thus guaranteeing reduction in plant stopping times. portions of the bundle.
Just like MEF express, MEF mobil also comes in the The Bundle Tutor features some independent telescopic
Navy version. In view of the unusual nature of its off- hydraulic beams to ensure balancing and adaptation of
shore application, the dimensional details of MEF Navy the Bundle Tutor to the geometry of the tube bundle
are based on the designed installation specifications longitudinal extension Y: +1000 mm (39.4”) on each
provided by the final client or engineer in change of the side.
project in a spirit of close collaboration. It also has a symmetrical jaws opening and closing
system relating to the axis of the tube bundle to ensure
MEF Truck perfect centering (transverse opening X: +600 mm
MEF Truck, thanks to the original project of the (23.6”) on each side.

IndustrIal Plants - May 2018
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