Comparison of Properties of Single Jersey Knit Fabrics Knitted With Single and Double Ply Yarn of Same Resultant Count

The constructional properties of a weft knitted fabric depends on stitch length and yarn count. In this paper it is searched that whether yarn ply affects the properties of weft knitted fabric though knitted from yarns of same resultant count. For this fabric samples were knitted with pairs of single ply and double ply yarns with the same resultant count. Then the constructional properties like course / cm, wales / cm, stitch density, G.S.M. and spirality were measured. 10 data for each property from each sample were taken and averaged. From the averaged data graphs were constructed to make the comparison. From the graphs it is found that the properties (i.e. is course / cm, wales / cm, stitch density, G.S.M) is less in all of the sample knitted from double ply yarns than the fabric samples knitted from single ply yarns. Moreover though the fabric samples were made by the same settings of knitting machine but the stitch length is more in fabric samples knitted by double ply yarns. As the component yarns lose twist during doubling and twisting they become bulkier. For this stitches occupied more spaces in fabric made from double ply yarn. This lead to make the difference in constructional properties between fabric samples made from single ply yarns and double ply yarns of same resultant count

A STUDY ON CAUSES OF KNITTING MACHINE STOPPAGES AND THEIR IMPACT ON FABRIC PRODUCTION

Knitting machine stoppages cause loss of fabric production. The smooth running of knitting machine depends on yarn quality, knitting machine conditions and knitting production conditions. Knitting machine stops due to different causes. In this work it was found that the causes of stoppages are yarn breakages, set-off, machine cleaning and fabric roll cutting, yarn joining, needle breakages and oil problem. The major cause of knitting machine stoppage was machine cleaning and fabric roll cutting. It occupies almost 40.38% of total stoppage time. This cause lead to the production loss of 43.48 kg of fabric. Similarly, yarn breakages, set-offs, and other causes like yarn joining and needle breakages occupied 20.19%; 7.69% and 31.7% of total stoppage time respectively. The knitting machine was stopped for total 312 minutes among 24 hours or 1440 minutes of running due to all of the causes. The causes, combindly led to production loss of 107.66 kg of fabric in 24 hours. Due to the all of the causes total 21.66% of fabric production loss was realized

A STUDY ON CHANGES OF DIMENSIONAL PROPERTIES OF GREY KNIT FABRIC DUE TO WET PROCESS

Intension of this work was to find out the changes those occur in knit fabric due to wet-process. To study this four single jersey grey knit fabric samples were taken and the properties courses per cm, wales per cm, stitch density, stitch length, tightness factor and G.S.M. were measured. Then they were subjected to go through a full wet-process cycle which is practiced in knit dyeing factories, i.e.; scouring-bleaching, enzyme process, dyeing, wash-off and finishing with softener were done. The samples were then dried and properties courses per cm, wales per cm, stitch density, stitch length, tightness factor and G.S.M. were measured. Finally they were compared with the properties of their respected grey samples. It is very difficult to predict the properties of a knit fabric before they are produced or received a wetprocess treatment. Which leads to difficulties between two sections namely, the knitting section and the finishing section. The authors hope that this work will increase the understandings between the two section

An Investigation on The Effect of Machine Gauge on the Properties of Weft Knitted Fabric

To investigate the effect of machine gauge on properties of weft knitted fabric, three V – bed knitting machines of different gauges were selected for fabric sample production. They were of gauge 7, 12, and 14. With these three machines, three 1 × 1 rib fabric samples were produced by using 20 / 2 (Ne) yarn. Keeping the same machine settings, 1 × 1 rib fabric samples were produced by using 32 / 2 (Ne) and 40 / 2 (Ne) yarns. The dimensional properties like course / cm, wales / cm, stitch density per square cm, and G.S.M. were measured from the samples. They were tabulated and presented by graphs to observe the effects. To analyze the effects, the stitch length of each fabric’s samples was measured. It was found that the stitch length increases as the machine gauge decreases and vice-versa. As a result, all other properties like; course / cm, wales / cm, stitch density and G.S.M. also changes. It was concluded that the machine gauge affects the knit fabric properties and it has a specific trend

A STUDY ON CHANGES OF DIMENSIONAL PROPERTIES OF GREY KNIT FABRIC DUE TO WET PROCESS

Intension of this work was to find out the changes those occur in knit fabric due to wet-process. To study this four single jersey grey knit fabric samples were taken and the properties courses per cm, wales per cm, stitch density, stitch length, tightness factor and G.S.M. were measured. Then they were subjected to go through a full wet-process cycle which is practiced in knit dyeing factories, i.e.; scouring-bleaching, enzyme process, dyeing, wash-off and finishing with softener were done. The samples were then dried and properties courses per cm, wales per cm, stitch density, stitch length, tightness factor and G.S.M. were measured. Finally they were compared with the properties of their respected grey samples. It is very difficult to predict the properties of a knit fabric before they are produced or received a wetprocess treatment. Which leads to difficulties between two sections namely, the knitting section and the finishing section. The authors hope that this work will increase the understandings between the two section

11-Year Trend of Mortality from Fatal Road Traffic Injuries in The Center of Iran; a Cross-sectional Study

Introduction: Road traffic injuries (RTIs) are one of the major health problems in developed and developing countries. In Iran, RTIs are the first leading cause of years of life lost (YLL). So, the present study investigated the 11-year trend of RTI- related mortalities in Iran. Methods: This study was a population-based cross-sectional study. All-cause deaths as well as RTI-related mortalities’ data were collected from the Civil Registration Organization (CRO) and Legal medical organization (LMO) of Isfahan during 2011-2021. The mid-year population, number of deaths due to RTIs, the crude and age-standardized mortality (per 100,000) of RTIs, and the percentage of proportional mortality by sex and year of accident during the study period were calculated and reported. Also, trend analysis was done using join point regression program. Results: During the study period, 11,248 deaths occurred due to RTIs in Isfahan province. 8,894 cases were male (79.03%), the highest number of deaths in both male and female cases was reported in those aged 15-39 years. Among the males, trend of standardized mortality in 2011-2015 was decreasing (annual percentage changes = -6.76(CI 95%: -2.53, -15.03)), while in 2015-2021 it was increasing (annual percentage changes = 3.00 (CI 95%: 0.63, 9.87)). However, no significant trend was observed among females. Conclusion: The findings of the present study showed that the number and standardized mortality rate of RTIs decreased during the 11-year period. It seems that applying stricter policies, improving the quality of the roads of the province, improving the quality of cars, and increasing the number of hospital and pre-hospital medical facilities can play an effective role in reducing RTIs

Determination of Optimum Speed of a Knitting Machine by Analyzing the Different Parameters

The objective of this research was to determine the optimum speed of a knitting machine. This study compared the different parameters of a knitting machine running at various speeds. For this, a knitting machine of 22-inch diameter and 24 gauge with 66 feeders knitting 24 Ne yarn was selected and was run at 40 rotations per minute (r.p.m.).; 42 rotations per minute (r.p.m.).; and 44 rotations per minute (r.p.m.) for total 24 hours for each speed. Data was collected for two days for 12 hours each. The different causes of stoppages were recorded with their frequencies and time for total of a 24 hours. Again, actual fabric production and the defective amount were recorded in kg. Moreover, different machine problems (like needle breakage, oil problem etc.) that occurred during the machine running was also recorded. Finally, the efficiency at different speeds was calculated with the help of calculated production and actual production of the knitting machine. Considering the stoppage data, machine efficiency, defective fabric production, and different machine problems, it was found that the optimum speed for the knitting machine is 40 rotations per minute among the three different speeds

Synthesis of micro-mesopores flowerlike γ-Al2O3 nano-architectures

The micro-mesopores flowerlike γ-Al2O3 nano-architectures have been synthesized by thermal decomposition method using the synthesized AlOOH (boehmite) as precursor. After calcination at 500°C for 5 h, the obtained flowerlike γ-Al2O3 has similar structure like the AlOOH precursor. X-ray diffraction (XRD), FTIR, TG, FESEM and TEM techniques were used to characterize morphology and structure of the synthesized samples. The specific surface area (BET), pore volume and pore-size distribution of the products were determined by N2 adsorption-desorption measurements. The flowerlike γ-Al2O3 showed BET high specific surface area 148 m2 g-1 with total pore volume 0.59 cm3 g-1