Productivity in simple terms is output expressed as ratio of the input. Productivity means doing things right at the least possible cost in the least possible time with the highest possible quality and to the maximum level of satisfaction of the customers and the employees. In other words productivity is synonymous with the production of the product quality required by the end-users at competitive price. Productivity is, therefore, key to the survival of a manufacturing enterprise in business. The confidence and satisfaction of the customers can only be gained on the basis of productivity which leads to repeat orders and business success.

Arif Iqbal Rana [1] emphasises the importance of measurement of productivity because what gets measured, gets managed; what gets managed, improves. Qureshi and Rana [2] confirmed on the basis of a study of knitwear sector of the textile industry of Pakistan that productivity measurement led to productivity improvement. After a study of over 400 plants in the U.S.A. Fein [3] reported that work measurement programmes alone increased productivity by an average of 14.60%.

1. Ounces/spindle shift (OPS)

Criterion most commonly used by the spinning mills in Pakistan for the measurement of productivity is ounces per spindle shift (OPS) for each count under manufacture. OPS is average actual output of a spindle operated for eight hours. First step is to calculate 100% OPS which is multiplied by the operating efficiency to get actual OPS count-wise. Thus, OPS reflects efficiency of machine performance, maintenance services, doffing operations, piecing operations etc. However, it does not indicate the total number of workers employed by the concerned spinning mills in relation to the total daily or monthly production.

2. Number of workers per thousand spindles/shift

It is a regular practice in the best practice mills to calculate the number of production workers per thousand spindles per shift, relate it with production, average OPS for overall average count, compare it with corresponding number of production workers employed in sister mills etc. and thus evaluate worker efficiencies.

3. 20's conversion

20's conversion is very useful criterion for the assessment of productivity of a spinning mill. This involves conversion of actual OPS of any count to OPS if 20's was being produced at the speed of the given count. On the basis of 20's conversion values of various counts being produced by a spinning mill, its performance can be compared with other mills. Thus, 20's conversion provides a valid basis for comparison of productivity from mill to mill.

In addition to the above, the South India Textile Research Association, Comboitore, uses a number of criteria for productivity measurement out of which the following are briefly explained as under:

4. HOK
HOK is an extremely useful criteria for the measurement of productivity of spinning mills and is widely used in the spinning mills of the world. HOK is calculated at each stage of production in a spinning mill.

It is equal to the number of operative hours required to produce 100 KGMs. of yarn. Calculations of HOK in the case of a spinning mill of 17280 spindles producing [14157] KGMs. of yarn, average count 20.54 are as follows:

5. Adjusted HOK
For calculating adjusted HOK, first step is to calculate the total of the standarised ring spinning production in individual counts for which conversion factors are calculated as follows:

Conversion factors for HOK = HOK for a given count

HOK for 20's or any other standard count

This method avoids break-up of operatives according to each count. Calculations of conversion factors and standarised production in KGMs in the case of above referred spinning mill are as under:

Adjusted HOK for Ring Spinning =

Adjusted HOK for back process stages can be calculated in a similar manner.

6. Spindle utilisation SH
Measure of spindle utilisation SH is ratio of average spindle hours worked per day divided by the No. of spindles installed. The number of spindles installed in the above refered spinning mill are 17280. Average spindle hours worked per day is calculated as follows:

One machine overhauled daily, stoppage for 12 hours and two machines cleaned daily in the ring shed, stoppage 4 hours each.

Number of spindle hours worked on:

33 ring frames = 480 x 33 x 24 = 380,160
2 Ring Frames = 480 x 2 x 20 = 19,200
1 Ring Frame = 480 x 12 = 5760
Total = 405,120
Spindle utilisation SH 405120 = 23.44
17280

In conclusion, it may be stated that by applying the above mentioned criteria, spinning mills can not only measure their respective productivities make inter-mill comparisons but also achieve improvements by better utilisation of inputs of raw-materials, man-power and machines etc.

Acknowledgement
Useful information received from Mr. Murtaza Ali Hasan, Adeelur Rahman Khan, Syed Shujaat Ahmed (Final year Students) during the preparation of this paper is gratefully acknowledged.

References

1. Arif Iqbal Rana, "The Wrong Measure", Productivity Journals, first national productivity conference, Islamabad, 2002, Vol I, issue III.

2. Qureshi, Z. and Rana A, "Factors influencing productivity in the knitwear sector in Pakistan, Malaysian Journal of the Small and Medium Enterprises, July 1998.

3. Fein Mitchell, "Work measurement and wage incentives, Industrial Engineering, September 1973.