PERFORMANCE IMPROVEMENT THROUGH STANDARD SETTINGS

Prof. H. R. Shah and A. D. Posugade

We are aware that at present about 95 percent of fabric is being produced in decentralized sectors of India. Remaining only 5 percent of total volume of fabric is produced by the organized sector. Previously, the small-scale units were working with power looms. Now, there are many units with automatic looms like Cimco, Ruti B, and Ruti C looms. There are units with shuttle-less looms also.

The scenario of fabric manufacturing is changing, though at slow pace. The small-scale units are gradually shifting from power looms to the automatic and shuttle-less looms. This is imperative in the era of GATT and WTO; to have competitive edge over other countries in the international market. Today, the customers ask to supply the fabric produced on the automatic or shuttle-less looms. This has forced the small units to adopt these technologies. It is because these types of looms guarantee quality and production. As such, it is expected in near future that many entrepreneurs will shift to automatic and shuttle-less looms.

One of the drawbacks of the fabric manufacturing in decentralized sector is that, many unit owners are reluctant to employ the qualified and experienced technical staff. Rather, the machine over looker is paid much higher wages and they are handed over the total responsibility of the shed. It is observed that the over looker can practically work on the looms and put the looms in production. But, he cannot pay more attention to correct settings of the different mechanisms, periodical checking of the critical motions, preventive maintenance of the looms and many such important aspects that affect the performance of the looms. This results in deteriorating the quality and the productivity of the looms. This in turn results in the non-realisation of the price offered by the customers as they refuse to pay on the pretexts of bad quality. This indicates the scope for improvement in the performance of small units through standardized machine settings and preventive maintenance.

Sulzer is a well-known successful name in the shuttle-less weaving. It is known of this machine that, its design is complex and the parts are made with high precision. Therefore, the accuracy of the settings is most important for good performance of the machine with respect to quality, productivity and brakeage of the critical parts like gripper, picking shoe etc. These parts are very costly.

In reputed organised mills the performance is much higher due to proper maintenance of all the aspects needed for it. One of the students from this institute collected detailed information regarding the settings to be kept on different models of Sulzer looms. These were followed in that esteemed mill in Mumbai.

On his return, the information collected by him was examined carefully for its usefulness in the local units. In Ichalkaranji, there are two weaving sheds with Sulzer looms. A visit was made to this unit to observe the performance. It was found that the efficiency of the shed was much less and the breakage of the grippers was more compared to the mill in Mumbai. Therefore, it was thought to make use of the information collected to improve the performance of the shed.

At the out set discussions were held with the unit owner regarding this. After his consent, first, study was undertaken to assess the performance with the settings kept by the over looker in this unit. These settings were noted. The performance of the shed was assed on the basis of following:

1. Average production of fabric per day

2. Efficiency percent

3. Fabric faults per 100 meters

4. Breakdown of parts

The observations were carried out for about one and half month. The observations are tabulated in table 1.

Table 1

Average production of fabric per day

Efficiency

Average faults per 100 meters

Break down of grippers

End break rate

Weft break rate

The table 2 gives the list of the settings kept by the over looker of the shed and the settings suggested. The suggested settings were done on the looms at the time of new beam gaiting. Few looms were personally monitored for the correct implementation of the new settings. Over the period of two months all looms were made to work with new settings.

Table 2

Sr. No.	Description	Old setting	New setting
1	Marks and keyways on shafts in receiving unit, middle tucking unit & on let cam plate	Slightly wrong	Straight up
2	Shed crossing	5^0	10^0
3	Distance between feeder gripper & scissors	0.55 mm	0.2 mm
4	Opener entry in gripper	0^0	10^0
5	Selvedge gripper (mm)	H-73, V-120	H-71, V-120.5
6	Scissor rack adjustment	2 mm	2.5 mm
7	Scissor cam plate adjustment	134 and 4.1 mm	133 and 4.4 mm
8	Change of pick gears	Loosely fitted	Tightly fitted
9	Height of cloth support	45 mm	47 mm
10	Feeder opener adjustment	103 mm	101 mm
11	Zero adjustment of torsion bar-gap between roller and picking cam	0.1 mm	0.2 mm
12	Picking lever adjustment- gap between picking shoe and projectile	0.15 mm	0.20 mm
13	Gap between expeller lever and expelled projectile position I	1.5 mm	2 mm
14	Upper position of projectile lifter above picking block	0.3 mm	0.4 mm
15	Gap between expeller lever and expelled projectile position II	2 mm	1.5 mm
16	Warp detector stop	275^0	300^0
17	Projectile detector setting	1.5 mm	0.8 mm

Table 2 Contd …

Sr. No.	Description	Old setting	New setting
18	Expeller position IV	1.6 mm	1.5 mm
19	Shed height adjustment	2 mm	3 mm
20	Warp stop cam adjustment	7.8 mm	8 mm
21	Adjustment of torsion bar twist	28^0	33^0

The correct settings of the shedding as stated in (2) and (19) were responsible for the reduced end breakage rate due to loose ends. This in turn resulted increased efficiency. The settings related to the gripper expeller and entry of the hook in the gripper jaws (4, 13, 15, and 18,) ensured the exact penetration of the hook in the dead center of the jaws. Due to this gripper breakage is reduced substantially. The tight fitting of the pick gears (8)eliminated the incidences of the starting marks. The adjustments related to the feeder, scissor rack and cam (5, 6, and 7,) resulted in the reduction of the weft related stoppages and defects. The setting of the warp detector stop (16 and 20) eliminated the warp stop motion failure due to this setting. Thus, reducing the defects related to the warp stop motion.

Study was taken to know the effect of new settings after the completion of the change of the settings on all the looms.

Table 3 indicates the results after the new settings.

Table 2

Average production of fabric per day

Efficiency

Average faults per 100 meters

Break down of grippers

End break rate

Weft break rate

The same was conformed by the unit owner through a certificate issued by him.