The practice of running a loom and replacing the pirn in a shuttle
Dr.K.N. Chatterjee
Prof.,& Head of FAE department
Head, Research and Consulting
TIT Bhiwani
Haryana, India.
While starting a weaving machine, a weaver should know about the sequence of operations to be carried out as under:
1. Checking the condition of the parts before starting the loom and clean them.
a. Weaver’s beam
b. Let off mechanism
c. Take up mechanism
d. Crank & crankshaft
e. Sley, race board and reed
f. Shuttle boxes & shuttles
g. Starting handle and brake
h. Emery & cloth roller
i. Top rollers (for heald shaft movement from top)
j. Tie rods (for heald shaft movements from the underside)
k. Loom crown
2. Running the looms, replacing the pirns in the shuttle, attending breaks and unweave and correct the damages in the fabric
a) Loom to be at the correct position before the start.
b) Two shuttles on each loom should be in good condition.
c) Shuttle in the box should have groove and eye in the front.
d) Shuttle box spring should grip the shuttle properly, neither too tight nor too loose.
e) Yarn of the pirn should be properly passed through the shuttle guide/eye so as to be released smoothly, without obstruction.
f) If there are nylon loop tensioners provided in the shuttle, the same should be in good condition.
g) The loose end of yarn from a fresh shuttle should be attached to the temple before inserting shuttle in the shuttle box.
h) Fresh pirn in the empty (extra) shuttle should be fixed immediately after starting loom with a new pirn.
i) There should be a sufficient number of weft pirns available on each loom.
j) Empty pirns should be kept in a separate box and not mixed with full pirns.
k) At the start, 1-2 picks should be inserted holding starting handle with hand, out of its notch. If there is no problem, starting handle should be pressed into its notch.
l) Warp shed should be clearly open such that shuttle does not fly out.
m) Brakes should stop loom in the right position.
n) Loom should always be rotated in the right direction for any operation.
o) The fresh pick should be inserted in a new warp shed and two picks should not be inserted in one shed.
p) If there is a double pick at fell of the cloth, it should be removed, the fabric should be loosened slightly by take-up release and reed at the front centre.
q) There should not be any starting mark when the loom is started after a stop.
r) There should not be any thick & thin weft bars (Jhiri& Patti) in the fabric during weaving.
s) In the event of a warp break, loom should be immediately stopped and broken warp should be tied with extra ends with a weaver’s knot and then drawn in the right heald wire and right dent of the reed.
t) If a slub, thick yarn, big knot or long tail end is observed in warp sheet, loom should be stopped and a fresh yarn should be tied in place of defective yarn.
u) If there is a patch of floating warp & weft (Jala), it should be removed by stopping the loom and unweaving the defective part of the fabric and then loom should be restarted properly.
v) If warp has a colour pattern, it must be ensured that the pattern is maintained as it is while attending warp breaks.
w) The operator should keep on patrolling around the running looms and see whether there is any problem which may lead to stoppage of the loom or may create a defect in the fabric. In such an event, precautionary action must be taken immediately.
3. To maintain optimum possible production with good quality in respect of patterns, proper picks, thick & thin places, broken threads, clear selvedge, cloth cover, starting marks etc.
a. Weaver’s beam
b. Let off mechanism
c. Take up mechanism
d. Crank & crankshaft
e. Sley, race board and reed
f. Shuttle boxes & shuttles
g. Starting handle and brake
h. Emery & cloth roller
i. Top rollers (for heald shaft movement from top)
j. Tie rods (for heald shaft movements from the underside)
k. Loom crown
2. Running the looms, replacing the pirns in the shuttle, attending breaks and unweave and correct the damages in the fabric
a) Loom to be at the correct position before the start.
b) Two shuttles on each loom should be in good condition.
c) Shuttle in the box should have groove and eye in the front.
d) Shuttle box spring should grip the shuttle properly, neither too tight nor too loose.
e) Yarn of the pirn should be properly passed through the shuttle guide/eye so as to be released smoothly, without obstruction.
f) If there are nylon loop tensioners provided in the shuttle, the same should be in good condition.
g) The loose end of yarn from a fresh shuttle should be attached to the temple before inserting shuttle in the shuttle box.
h) Fresh pirn in the empty (extra) shuttle should be fixed immediately after starting loom with a new pirn.
i) There should be a sufficient number of weft pirns available on each loom.
j) Empty pirns should be kept in a separate box and not mixed with full pirns.
k) At the start, 1-2 picks should be inserted holding starting handle with hand, out of its notch. If there is no problem, starting handle should be pressed into its notch.
l) Warp shed should be clearly open such that shuttle does not fly out.
m) Brakes should stop loom in the right position.
n) Loom should always be rotated in the right direction for any operation.
o) The fresh pick should be inserted in a new warp shed and two picks should not be inserted in one shed.
p) If there is a double pick at fell of the cloth, it should be removed, the fabric should be loosened slightly by take-up release and reed at the front centre.
q) There should not be any starting mark when the loom is started after a stop.
r) There should not be any thick & thin weft bars (Jhiri& Patti) in the fabric during weaving.
s) In the event of a warp break, loom should be immediately stopped and broken warp should be tied with extra ends with a weaver’s knot and then drawn in the right heald wire and right dent of the reed.
t) If a slub, thick yarn, big knot or long tail end is observed in warp sheet, loom should be stopped and a fresh yarn should be tied in place of defective yarn.
u) If there is a patch of floating warp & weft (Jala), it should be removed by stopping the loom and unweaving the defective part of the fabric and then loom should be restarted properly.
v) If warp has a colour pattern, it must be ensured that the pattern is maintained as it is while attending warp breaks.
w) The operator should keep on patrolling around the running looms and see whether there is any problem which may lead to stoppage of the loom or may create a defect in the fabric. In such an event, precautionary action must be taken immediately.
3. To maintain optimum possible production with good quality in respect of patterns, proper picks, thick & thin places, broken threads, clear selvedge, cloth cover, starting marks etc.
1. 4. basic functions performed by a Shuttle, pirn, and its major parts:
Shuttle: It is a wooden tool which is used to carry the weft thread through the shed.
Pirn Winding
In conventional weaving, weft insertion is done through a shuttle projected through the warp shed (opening two sets of ends by heald frame). Picks carrying bobbin is called “Pirns”.
5. The shuttle and pirn (quill) types, the passage of weft yarn through the shuttles
The shuttle is usually made of hardwood and is typically between thirty and forty cm long. it's a pointed steel tip at either end. The weft yarn is in the form of a pirn (quill), a long slim package wound in such a way that the yarn can be withdrawn substantially axially from one end without the package itself being rotated. The pirn is always as large as can be accommodated within the hollow shuttle and typically contains from 30 to 60 grammes of yarn.
Parts of Shuttles:
Shuttle with spindle:
a) Spindle: Shuttles of this type are having spindle which carries the pirns in tight condition.
b) Eye: Shuttles of this type are having eye through which weft yarn passes.
b) Eye: Shuttles of this type are having eye through which weft yarn passes.
Different parts of a shuttle are given in table1 as shown in figures 4 and 5.
Alphabet
name
|
Name of the part
|
Description
|
A
|
Shuttle
|
Used for carrying the pirn for weft insertion
|
B
|
Spindle
|
For holding the pirn firmly
|
C
|
Shuttle eye
|
For the easy passage of weft yarn
|
D
|
Pirn/Quill
|
For carrying weft yarn
|
E
|
Weft Yarn
|
For weaving purpose
|
Joining of broken warp and weft yarns:
A weaver should be able to join the broken ends with the help of Weaver’s knot, which is a special knot used only for joining a broken warp or weft yarn/thread. It does not slip
Drawing-in of warp ends through the heald eyes:
A weaver should be able to draw the warp ends through the heald eyes according to drafting plan or drawing-in order of a particular weave with the help of drawing hook.
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