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with stock shorter than 176 inches, and it fails entirely below one inch.
The first effect of a bad piecing on short cotton is the frequent breakage of the slivers on the comber. table, causing frequent stoppages, reduction of the already small production of the Heilmann and an excessive amount of waste sliver. The bad piecing cannot be obliterated at the comber draw box, and the result is a weak sliver all through the draw frames with frequent stoppages and large quantities of waste to be returned to the scutching room, after labor has been expended upon it. The weak slivers and consequent frequent piecings at the comber and draw frames, make themselves felt in the form of irregularities in the yarns. From this it will be seen that one of the chief difficulties in connection with the combing of short cotton lies outside the comber itself, and is caused by the weakness of the slivers due to bad piecing.
To obviate these difficulties, the Pinel Lecoeur comber was nvented and made by HETHERINGTON, and it reduced the waste made in combing short cotton and made a fair piecing even with 5/8 inch Surat cotton. The writer erected nearly all the machines of this type that were made for European mills, and most beautiful hosiery yarns of coarse counts were made from 5/8 inch Surat cotton, with about 23 per cent. of waste, which was collected right at the comber into a sliver and passed through draw frame slubber and intermediate, and spun at once into 4's yarn, whilst cloths of excellent qualities were produced from one inch American cotton.
But this machine failed to make the combing of short cotton a commercial success, for the following reasons:
(1) Its production was not greater than that of a Heilmann, and although it made a better piecing in appearance, the sliver was not amalgamated at the piecing and drawn together, but simply overlaid.
(2) The waste was still too high, rendering the process expensive.
(3) The machine was complicated and difficult to set.
The Nasmith comber is now happily well known, nearly 2,000 being at work, and one of the attributes of this machine is its capability of dealing much more satisfactorily than its predecessors with staples between 56 inch and 118 inches, for not only does it produce double the weight per machine, but it renders it possible to comb these short staples without excessive waste, the two essentials to make such combing commercially practicable. In addition to this, it makes a piecing, which, even on these short cottons, is practically perfect.
In all combers except the Nasmith, the piecing consists simply of laying the tips of one lot of fibres over the tails of the previously detached series, the overlap being about 12 inch on long cottons, and with short cottons, no sliver can be made that will hold together along the table. But the nature of the piecing in the Nasmith machine is quite different, there being not only a long overlap much exceeding the length of the staple on the short cottons, but the ends are thoroughly amalgamated by being drawn in whilst the overlap is being made. This does away with the serious difficulty of manipulating the combed slivers at the subsequent operations, and makes such operations quite normal in character, causing neither excessive waste, nor stoppage. A sliver of 74 inch cotton taken just before entering the draw box on a Nasmith, can be raised from the table and will sustain its own weight for the full length of the table, which provides ocular demonstration of the soundness of the piccing.
In the hosiery trade, the machine has long ago established itself as the best for the purpose, and there is at the present, a growing demand for combed American yarns of medium counts.
A little consideration will show the difficulties in the way of combing short cotton, without taking out too much waste. In Sea Island cotton for instance, neglecting a small percentage of mere fluff, we have all lengths of fibres between 4 inch and two inches, and it is comparatively easy to select, in combing, all those below one inch and comb them out. But in one inch stock, the difference in length between the long and the short fibres is much less, and it becomes increasingly difficult to select only the short, as the difference decreases.
The technical point which renders it possible to comb short cotton on a Nasmith comber without excessive waste, is that the nipper can be brought very close to the nip of the detaching rolls with just space between for the top comb, so that there is only half the diameter of the detaching roll between the top comb and the nipping point of the rolls, instead of the full diameter of leather covered detaching roll, as explained above.
As regards the actual work of the machine, it may be said that 850 pounds of combed sliver of good quality can be produced weekly per machine, on one inch stock, and with waste from 15 per cent. to 20 per cent., according to quality required.
Another point of utility of the Nasmith comber has been recently developed in European mills, namely, the recovery of the good cotton in the strips from the flats of carding engines, and in this connection, the following data may be of interest, and it must be noticed that the yarn made from the combed flat strips, is always much stronger than the carded. yarn made from the original cotton.
Test of 100 pounds of Card Flat Strips.
American (Orleans) Cotton passed through Combined Creighton Opener and Scutcher, Revolving Flat Carding Engine, one head of drawing and made into laps on the Sliver Lap machine preparatory to combing on the Nasmith Comber.
Loss at Combined Opener and Scutcher,
7 pounds, 6 ounces. 16 pounds, 2 ounces. 19 pounds, 2 ounces. 42 pounds, 10 ounces.
Total weight of finished Sliver ready to be put up at the third head of drawing,
57 pounds, 6 ounces.
COMPARISON OF COST AND PROFIT.
Value of 570.375 pounds of Combed Sliver at
778d per pound, £18 14 4 Value of 190.1 25 pounds of Comber Waste at 340 pound,
Value of 1,000 pounds of strips at 234d per pound,
[11 9 WAGES : Blowing room,
13 5 £12 17 7
Less value of 1,000 pounds Strips and working expenses,
£12 17 7
Total Net Profit from 1,000 pound strips which one Nasmith
comber will treat in one week of 50 hours under normal conditions,
Test of Cops spun from Combed Flat Strip, as against the ordinary yarn: — Waste made on comber, 24 per cent.
Test of Cops spun from one end of combed strip sliver mixed with seven ordinary ends at the draw frame.
Ordinary Yarn Twist Cops.
Yarn from one end of strip.
Average of six wrappings,
Seven of ordinary sliver,
Mr. STEPHEN C. LOWE. You have before you these figures on a reclamation plant. I will say that these figures are from actual tests in England and can be fully corroborated here.
Has anyone anything to say on this
The PRESIDENT. subject?
Mr. ARNOLD B. SANFORD. I would like to ask what is the width of lap, and how many heads to the machine ?
Mr. STEPHEN C. LOWE. The machine is made in two sizes. This machine is made in 101 and 12 inch laps, six heads to a machine only. This test was made on a 10 inch lap. These tests are from that size machine; 18 per cent. more is gained by the wider lap, the 12} over the 10.
Mr. JOHN A. FERNLEY. Mr. President, I would like to ask the difference between the production of the Nasmith against the Heilmann on the same staple of cotton.