Mitsubishi maf serie milling and boring machine

HISTORY OF THE MAF MACHINE
In 1957, Híroshima Machíne Tool Works of Mitsubishí Heavy lndustries, Ltd. made the technícal tíe-up on the Mílling Boring & Combíned Machíne desígned by Mr. C.W.
Berthíez, a world renown designer of machíne tools, and advanced into the field of large-sized machine tools with ínítíatíon of manufacture of the so-called MIB machíne.
The MIB machine has been highly appreciated among users ín a varíety of industríes not only in Japan but ín European countríes and also in the u.5.A., as a machíne developed
challengíng to a new field of combíned machining.
Various MIB machínes numberíng to about 150 units have been manufactured and delivered over the períod of 8 years until the contract expired in 1967. In the meantíme, to
meet every conceivab1e requirement of users in the times of technícal ínnovatíon, we have acquíred a number of techniques on manufacture and utilization of large-sízed
machine tools while adding ímprovement to the machíne.
Thus, the MAF Machine was developed and more than 100 machines of various models including numerícally controlled models has been delívered up to date.
The photo shown below ís a birds-eye-view of the whole Hiroshima Machine Too1 Works embedded within an envíronment most suitable for building precision machíne tools such
as the MAF Machíne. The white roofed long buílding is the No.1 large-sized machíne tool shop whích has a capability of building five MAF 200/135 machínes per month. The
larger but shorter buildíng adjacent to the No.1 shop ís the No.2 large-sízed machine tool shop where the larger MAF 340/225 machínes weighíng up to a total of 300 tons are
assembled.
These two shops have been buílt without provídíng wíndows to ensure proper aírcondítioning because severe precisíon ís demanded regardless íts síze. Moreover, the foundatíon of the shop floor has been constructed through the most up-to-date techníque of civíl engineeríng work.

STANDARD EQUIPMENT AND SCOPE OF SUPPLY

Tool lockíng device íncludíng 5 pull studs
Dígítal readout device M-NUX115 (for X, Y and Zaxes íncludíng ínductosyn scales and slíder)
Electrícal equípment and electríc wíríng materíals
Electrícal wear parts (brush, lamp, etc.)
Bed cover (telescopíc type)
Levellíng block
Thread cuttíng device (for MAF 340/225 only)
Maíntenance tool kít
Remarks:
1. Conforms to the Japanese 1 ndustríal Standard J1S B 6101 (Taper 7/24).
2. Applicable on1y to the column feed.
3. The wíríng materíal between power source and control panel ís not included.
Power source ís AC 220V except for MAF 340/225 whích ís AC 440V.
Pressurízed shop air (pressure: 2 to 7 kg/cm2 flow rate: 100 1/min.) for oi1 míst lubrícatíon of the main spíndle bearíng must be prepared by the customer.

The most promínent feature of the MAF inachíne seríes is that high rigíd headstock can be moved in its axial directíon.
The headstock is of box type closed construction wíth larger sectíonal area and hígher rígidity than other types, for example, ram type, quill type, etc. On the front plate of the headstock, the most suitable attachment can be mounted accordíng to workpieces, and the headstock can be moved ín the axіal directíon with large attachment kept mounted, thus
enables great accessibílity to the workpíece and further, permittíng the machíne to dísplay íts full performance.
Generally speaking, the center of gravity of the machíne will shíft as the headstock
moves out, causing inaccuracies in precisíon. However, in the MAF inachine series, a unique balancing system ís adopted according to the size of machine, whereby
the displacement is restraíned and assures a straight horizontal movement.
Additional feature of the balancing system is that the weight acting upon the saddle
guideway is decreased. Along with this feature, hydrostatic bearing is employed
to the guideways whích reduces the dynamic friction duríng motion which
results to a smooth headstock dísplacement.

MAF 200/135A MAF 210/150A
The headstock and saddle are balanced by a new balancíng system consistíng of two
chaíns. One end of the two chaíns are fíxed to the counter-balancíng weight with
the opposíte end supportíng the headstock dírectly through rollers. The rollers
support the hardened tapered cam plate located behínd the headstock. The headstock in turn supports the saddle through belleville springs and rollers. When the
headstock ís fed forward in íts axial dírection, the front tapered cam plate
produces tension to the front chaín. Thís tensíon, therefore, compensates for the
ínclinatíon of the headstock to maintaín a straight horízontal movement.

MAF 260/180 MAF 340/225
The headstock of inedium-and large-sízed machines become larger and heavíer where
large attachments are more oftenly used.
The balancíng system of the headstock, therefore, differs in principle to that of
the smaller machines. The headstock and saddle are Ьalanced separately with índependent counter-balance weíghts. The headstock ís counter-balanced by two chaíns wíth each end of the chaíns connected respectively to the center of gravity of the headstock and of the
counter-balance weight. (One chain ín case of the MAF 260/180). The arm(s)
supporting the headstock moves in or out synchronízed with the movement of the
headstock through a gearíng, spline shaft and synchronizing chain mechanism. Thus
assuring a straíght, horizontal movement.
Another advantage of this mechanism ís that the supporting end of the chaín(s) at
the headstock end can be adjusted to compensate for the shíft of center of
gravity when heavy attachment is mounted to the headstock.

MAIN BEARING AND TOOL LOCKING DEVICE
Two angular contact ball bearíngs which are mounted backto-back and a double row cylíndrícal roller bearíng are employed to support the míllíng spindle and the concentríc
boring spindle whích ís a vítal part of the headstock. These bearíngs generate less heat compared to taper roller bearíngs and whats more, the application of the oil mist lubrícatíon
to these bearíngs mínímízes temperature rise whích leads to
less thermal dísplacement.
Wíthín the boríng spíndle, a tool lockíng device for locking/ removíng the tools to or from the boríng spíndle ís íncorporated.
The tool lock/release pushbutton is located at a conveníent posítíon of the headstock, close to the boring spíndle, to ensure quíck and steady operatíon for changíng tools.
The set of balls of the tool lockíng device gríps the pull stud whích ís screwed into the rear end of the tool arbor and the array of compressed belleville spríngs keeps the tool locked
in place. To release the tool, a hydraulíc cylinder located behínd the tool lockíng device ís actuated.

RIGIDITY
The constructíon of large major components íncludíng the column is of a complete box type. The components are desígned paying partícular attentíon to the arrangement of
the ríbs to gíve the híghest rígídíty.
Double wall constructíon ís adopted to the guídeway wall síde of smaller machines and as shown ín the photo below, a hexagonal double wall of fabrícated steel design ís applied
to the column of inedíum-and large-sízed machínes. Needless to say, along with the above mentíoned constructíon, triangular ríbs are formed to províde ample dynamic rígídíty
to cope wíth cuttíng forces whích acts upon the machíne from every dírectíon.

HYDROSTATIC BEARING
For the guideways on which heavy load is applied, a uníque hydrostatic bearíng ís adopted which permíts effective oil floating, thus allowing smooth fíne feed as well as preventíng
metal-to-metal contact between the guideway and moving member.
Although a total moving toad of the column including the headstock and saddle of the MAF 350/225 reaches about 150 tons, a creep feed of 0.67 mm/min. to a high rapíd traverse of 6 m/mín. ís possible, thanks to the hydrostatic bearing. This hydrostatic bearing is also employed for the feed worm and worm racks.

The photo ín the right hand page íllustrates testing of the hydrostatic bearing of the D1T-B 30 X 30 Rotary Tab1e loaded wíth 100 ton deadweight.

CONCENTRATED MACHINE CONTROL
The larger the machíne is made, the greater ímportance ís placed on its controls. As the pendant control box, suspended from a long swivel arm, can be moved vertically and
horizontally by the motor, the operator can control the machine correctly at the most easy-to-operate posítion whíle confírming the movement of machine.
All operatíonal functions required are incorporated compactly and systematically wíthín the pendant control box. Two systems of feed control permíts two-axís símultaneous feed.
Every operatíon of the pendant control box can be made by the tip of the fingers. For ínstance, upon depressíng the selector pushbutton for the column movement, a lamp
incorporated within the pushbutton illuminates to índícate the column is unclamped and ready for operatíon.

Other moving members will be kept clamped unless theír respectíve selector pushbutton ís depressed.
The main spindle revolution and feed rate can easíly be set to a requíred va1ue through the potentíometer. A thyristor controlled static Ward-Leonard system adopted for the
control device provídes a stable speed control. In the medíum-and large-sízed machines, an electromagnetic clutch is used for changing the feed rate from high to 1ow, and vice
versa, and remote operatíon from the pendant control box is accomplished.
Also, ín MAF 200/135A and 210/150A, a varíable pulse control is employed over the whole range, to control the feed rate.

For reading the machíne positíon, Mitsubíshí digital readout M-NUX115 whích is
already híghly appreciated among users ís installed as a standard equipment. As for
the position feedback element, Mítsubíshi ínductosyn scale is used, thus enablíng a
very accurate and speedy posítíoning of the machíne and further ìmprovíng the
effícíency of the machíne.
Remarks:
- As an optional feature, the digítal readout
devíce M-NUX115 can be buílt-in to the pendant control box for Models MAF 260/180 and
MAF 340/225.
-For further ínformatíon of Mítsubishi M-NUX 115 dígítal readout devíce and Mitsubíshi
lnductosyn Scales, ask your nearest dealer or contact Mítsubíshí dírect.

ROTARY TABLE
It is a known fact that as workpieces become increasingly larger, one must consider how to increase the operational efficiency by decreasing the number of setups required for
machining. The answer to this question ís the utílízation of the rotary table.

According to the síze and shape of workpieces, various types of rotary table are requíred. Mitsubíshi has a wide seríes of rotary tables rangíng from a low 3 ton loading capacity up
to a high capacity 200 ton model.

Remarks
1. Tables of varíous sízes can be manufactured upon request.
2. The 1oading capacity of models can be increased through alteration of the hydraulíc círcuít or by provídíng antí-deflection table.
3. The followíng optíons are avaílable.
(1) Dígítal readout device M-NUX115 for reading linear or angular posítíon.
(2) Control pedestal for índependent operatíon of rotary table.
For further detaíls, please refer to the "Mítsubíshí Rotary Tab1e" catalog.

It ís necessary to select the proper attachments, accordíng to workpíeces, to
perform effectíve combined machíníng.
The following pages illustrates varíous models of attachments whích can be
selected accordíng to íts purpose. The schematic díagram shown ín pages 22 and
23 íllustrates some examples on how the attachments can be combined. The front
plate to whích the attachments are to be mounted is cleverly designed with a hígh
speed spindle whích ís used to dríve surfacíng heads and boríng tool heads and
a feed drive spindle whích enables to gíve a radíal feed to the attachments.

Floor Plate
Angle Plate
Levelling Blocks
The levelling blocks for the bed are equipped as a standard for MAF 200/135A and MAF 210/150A. For other models, order the number of levellíng blocks requíred.
Thread Cuttíng Devíce
This threading device ís helpful when cutting large díameter threads which cannot be accomplished by ordinary machine taps.
The range which can be covered by this device ís shown in the tabulation below.

Jíb Crane for Attachments
Thís jib crane wíll come ín handy for mounting attachments to the headstock. There will be no waste of time waiting for the overhead travellíng crane to do the job.
MAF 200/135A
MAF 210/150A
MAF 260/180
MAF 340/225
Capacity
1 ton
1 ton
2 ton
2.5 ton

The floor plate and angle plate can be applied to all models.
The dímensíons of the tee slots and keyways can be altered to meet customer requírements.

To keep pace with the large demand of machining centers, large machíne tools are puttíng effort ín up-gradíng theír performance. For ínstance, dígítal readouts are now commonly employed ín place of the híther-to-used optícal readouts and numerically controlled machínes are gradually coming into the picture.
In order to meet such needs, the líne-up of our New MAF series has been designed to be fully compatible.

To convert a standard MAF inachíne to a full NC machíne requíres no major alteration. The NC MAF inachíne has two versions—the general purpose NC machine or the Full Servo
Drive NC model.
A heavy duty Machining Center was actually realized with the MAF inachine by adding an ATC magazine, AAC and a numerically controlled D1T-A rotary table as illustrated in
the photo below. ... aп example of the Fu11 Servo Drive MAF inachíne.

Abstract Of NC Specifícatíon
■ 2-, 3-, 4- or 5-axis with both positioning and contouring modes of operation
■ 2- or 3-axís símultaneous línear and circular interpolation
■ Absolute and incremental programming
■ Accepts E1A and/or1S0 codes
■ Buffer storage
■ Feedrate override by infinítely adjustable potentíometer
■ 4-digít direct feedrate coding
■ Síngle axís or uníversal readout
■ Mirror image
■ Open or closed loop
■ Programmable dwell by g04 code.
■ Canned cycle
■ Tool length offset
■ Cutter path compensatíon

MAF MACНІNES IN OPERATION
More than a hundred MAF inachínes are now operatíng at varíous customers throughout the world. Here are some examples íllustratíng the varíety of workpíeces the MAF
machíne can handle.

Machining of Diesel Engine Frame
Milling of the top joint face of a large díesel engine frame using a right angle head with MAF
200/ 135A.

Aп Example of Double Loadíng
Machiníng of a low pressure turbíne casing set up on the floor plate whíle the other workpíece beíng loaded on a large rotary table
Model D1T-D 45 X 120. The Machíne is MAF 340/225NC.

Machíníng wíth Fu11 Servo MAF
Machíne
Accurate and quick positíoning with NC tape controlled machine
assures high production and hígh quality.

Idle Tíme Reduced wíth Double
Loading
Resetting of reduction gear casing can be done while the workpiece
(MAF column) on rotary table D1T-A 21 X 30 is being machined
with MAF 200/135A.

Typіcal Applícatíon of a Uníversal
Head
Deep faces beyond the throat of workpíece can be machíned effectívely by usíng the uníversal head UH-15 wíth standard support
S-250.

lnternal Contouring of Concentrator
Contouríng the ínternal of the heartshaped cam portíon at both ends and
millíng of grooves utílízíng circular ínterpolatíon.

Solvíng Setup of Long Workpíeces
Setup of long workpíece is facílítated by arrangíng the surface of the floor plate and top face of rotary table D1T-A 21 X 30 ín the same level.

Two Columns on a Common Bed
Two MAF 200/135A columns installed on a common bed wíth rotary table DIT-A 21 X 30.

Compensatíng Load on Rotary Table
Two parts can be machíned at the same setup whích also helps ín balancíng the load on the rotary table

Machíníng of Reductíon Gear Box
High precision boring of bearíng holes varyíng from 320 mm (12.598 inches) to 920 mm (36.220 ínches) in size.

Usíng Rotary Tab1e lnfeed wíth Long
Attachment
Millíng the ínternal faces of a press frame with MAF 200/135A using a universal head UH-15 and extension support SE1300. Hígh accuracy on the bolster face can be maíntaíned by using the ínfeed of the table.

Dríllíng of Blower Casíng
Dríllíng, reamíng and spot facíng of multíple períphery holes usíng canned
cycle and numerícally controlled indexíng with Rotary Table Model D1T-A 21 X 30 NC.