IMPORTANT PARTS OF LOOM (HEALDS):-

TYPES OF HEALD :-

Wire Healds:-

 Wire healds are made of round , flat or twisted wires, small loops being left in the center for the ends to pass. The wires are loosely placed on laths or bars or slider-rods D and self adjusting. Now a days wire healds are largely used in the cotton industry. When used for silk , the eyes of these healds are sideway to reed . Wire healds are said to last longer and equally suitable for close and open textures. The wooden framework A is held at the ends by the metal bar C by means of a couple of screws top and bottom. The flat wires healds are extensively used in the manufacture of high grade silk cloth. Wire healds are illustrated in figs.7A, 7B and 8.

Image of healds , heald shaft, wire Heald.

Fig. 7A, 7B and 8.

The increasing popularity of wire healds may be attributed to their ,

(,i) Lower cost, 

(ii) Lesser depreciation.

 (iii) Higher efficiency, 

(iv) Heavier weight and

 (v) Greater strength than cotton healds.  Knitted wires healds are heavier in weight than other wire healds and are used for heavy work. These healds last 15 to 20 years which are much longer than other wire healds . Cotton healds last much shorter than wire healds.

The apparent drawbacks of wire healds are;

 (i) Extra time taken to draw in warp.

(ii) Less flexible.

 (iii) Broken ends cutting contiguous warp threads.

(iv) Difficulty in repairing broken ends and (v) Easily damaged by pulling or rough handling.

Guaze and Doup Healds:-

The most efficient and latest healds for weaving guaze or Leno fabrics are illustrated in fig. 9.

Fig.9 Gauze or Doup Heald:-

There are two Doup and a slip. Each doup is made in two parts and may be termed as 'double heald '. The two parts are at A and C. The part A is cranked and has a small step at B . C is cranked at D and is made with a hole for the bottom part of the heald to pass through . At the upper part E the slot is longer , and has a step upon which the upper end of A may rest when threaded through. At the top half, the two healds are as one by inter locking , but at the bottom they are separate. The healds are slotted at both ends for the use of slider rods . The healds H and I are reversed in position. The total length of the healds is a 13.25" or 33.65 cms. and the slip F is 6.125 or 15.55 cms. long. 

 Both the legs and the upper end G of the slider rod are slotted. Through the half moon shaped end G of the slip , the crossing thread passes.

At M , the crossing thread is drawn through the slip G, and the stationary thread N is passed through the heald on the stationary shaft behind both doups, and the passed between the two doups. 

When the left doup 0 is raised, it takes with it the slip R . This causes the crossing thread T to be lifted on the left side the stationary thread S, and a pick is then inserted with the heald P down.

On the next pick the heald and slip are reversed in position, the heald U down and the heald V and slip W up. This completes weaving of simplest kind of guaze . It may be noted that the slip can not be pulled down any further than where the double healds J and K inter lock at their centers.

Limitations of Heald Shedding:-

Cotton or wire healds may give the most perfect form of shedding when a large number of warp threads move up and down in the same sequence. The space , that separates the front and back healds in a loom , determines the number of healds which may be conveniently, used is 20, whereas in the worsted industry it is 32. But in the handloom industry the maximum number of healds that may be controlled by weaver does not ordinarily exceed twelve.

 Another limitations to heald shedding is that a limited number of warp threads can be moved independently.

Healds are suitable for standard patterns, where curved lines are absent or present only to a limit extent. For elaborate geometrical or floral effects and for flowing lines a Jacquard machine is employed, but for small figures a dobby is found suitable.

Ref:-Weaving Mechanism Book Vol.I by Prof. N. N. Banerjee.