FIELD OF INVENTION
The present invention relates to an universal shroud locator block for root and
shroud milling on horizontal machining center machine. More particularly, the invention
relates to an universal shroud locating pad which can be used to locate every type of
blades that are being manufactured. Steam turbine blades have root, profile and shroud
portion. After considering the fixture and blades, an universal shroud locating pad is
invented.
BACKGROUND OF THE INVENTION
In New Blade Shop, final finished blades are machined from rectangular cross
sectional blanks in 5-axis CNC machines. The blanks are clamped in special clamping
adapters while carrying out the milling operation. So, technological allowances
(clamping allowances) are kept in the blanks while blanking operation is carried out.
Now, after completion of machining of the complete blade in 5-Axis machines, these
blades are loaded on HMC machines, where the clamping allowances are milled off and
radius is imparted on root or shroud as per requirement in drawing. The blade is
clamped in a special fixture in HMC machine, where four types of special pads are
designed to clamp blades of every variety. The four pads are namely, root locator,

shroud locator, root base pad and shroud base pad. Basically this pads align the axis of
the blades in both horizontal and vertical direction while clamping. Presently, length of
the root locator being fixed in the machine, we need to change the shroud locator block
as per design requirement. The height of the shroud locator was variable for every type
of design of blades and a variety of locators were needed to be designed each time for
new type of design of blades.
OBJECTS OF THE INVENTION
Therefore, it is an object of the invention to propose an universal shroud locator
block for root and shroud milling on horizontal machining center machine, which is able
to standardize the shroud locator so that the same can be used to locate every type of
blades that are being manufactured.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 showing the Arrangement of clamping in existing fixture.
Figure 2 showing the orientation of blade along with different clamping pads.
Figure 3 showing the general steam turbine blade and general calculation for
calculating the height of the shroud locator.
Figure 4
And showing the assembly of the universal shroud locator block.
Fig. 4 A

Figure 5 showing the sectional view of the universal shroud locator block.
Figure 6 showing the detailed view of the cover block.
Figure 7 showing the detailed view of the locator block.
Figure 8 showing the detailed view of the wedge.
Figure 9 showing the detailed view of the cassette.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
As shown in Fig.4 the new block (A) consists of a shroud locator block (3) having
four no of counter holes (7) which is clamped to the machine fixture base with help of
M10 bolts. The unit (3) is having a slotted portion (8) at the bottom where a wedge (5)
fits. The unit (3) is having a slot (17) (Fig.5) at the face where a cassette (10) is
positioned.
The cassette (10) is having a taper (16) at one side which guides with the taper
(15) present in the wedge (5). The cassette (10) gets fitted in the slot (17) of unit (3)
and rests on the taper (15) of the wedge (5). The movement of the cassette (10) is
fixed by tightening the grub screw M6 (9) which fits into the threaded hole (18) (Fig.7)
of unit 3. This is shown in Fig. 5 in Section A-A. The cassette (10) thus acts as an
adjustable unit, whose height is adjusted and fixed as per requirement.

The unit (2) is a specially designed cover block which is fitted with unit (3) with
the help of two nos of M10 bolts (1) which fits into two counter bores (12) (Fig.6). It
has counter bore (13) which suits a bolt of M6 (6) which tightens the spring (4) along
with the threaded hole (14) present in the wedge (5). This cover plate saves the
mechanism from chips generated during machining. The spring (4) acts as shock
absorber.
All the 4 units namely wedge (5), cassette (10), shroud locator block (3) and
cover block (2) (except the standard bolts, grub screws and the screw) are made of EN-
24 material. All are hardened and ground.

WE CLAIM
1. An universal shroud locator block (A) for root and shroud milling on horizontal
machining center machine, comprising;
a shroud locator block (3) having four number of counter holes for fixing with
machine fixture base with bolts;
a wedge (5) fitted into a slotted portion (8) of the said locator block (3);
a cassette (10) disposed in a slot (17) at the face of the said block (3);
a cover block (2) fitted with the locator block (3) with bolts through counter
bores (12);
a spring (4) disposed in a threaded hole (14) configured in the wedge (5)
tightened by a bolt passing through a counter bore (13);
Characterised in that,
the cassette (10) having a taper (16) at one side is guided with the taper (15)
present in the wedge (5) wherein the cassette (10) fitted in the slot (17) rests on the
taper (15) of the wedge when the movement of the cassette (10) is fixed by tightening
a grub screw (9) fitting into a threaded hole (18) of the locator block (3), wherein the
cassette (10) acts as an adjustable unit for adjusting the height and fixed as per
requirement, when the cover plate (2) saves the mechanism from chips generated
during machining, wherein the spring (4) is configured as shock absorber.

2. The universal shroud locator block (A) as claimed in claim 1, wherein the wedge
(5), the cassette (10), the shroud locator block (3) and cover block (2) are made of EN-
24 material, hardened and ground.