Wire Twisting Bows

Due to the varying needs in the market, bows are supplied on a made to specification basis. We presently manufacture bows of various sizes and shapes, with or without eyelets/guides and retaining hardware. Over the years, probably 80 different sizes have been produced in the following sizes:

From 192" in. x 6" in. x .3/4" in. (4876mm x 16mm x 19mm) down to 29 1/2" in. x 1" in. x 5/32" in. (750mm x 25mm x 3.9mm).

In addition, we manufacture bows for approximately 30 different machines in possibly three different materials. Some bows come with narrow mid-sections, some with chamfers on one or both sides and some with moulded or machined grooves Bows are supplied with two different wear strips or none at all. In addition, there are two main types of eyelets/guides, but there are have been about thirty different sizes we have been asked to supply to date.

Many times we are requested by customers to suggest which bow will last the longest or what is the price of our standard bow. To these questions, perhaps some of the following information would be helpful:

A. When bows fail the cause of such failure is almost always the fault of some external sources. Probably 98+% of the time bows are broken for reasons indicated in the attached list. Other times the failure may be attributed to poor design, poor manufacturing or poor grade materials. We use aircraft quality materials and have been satisfying the wire industry with our bows for over seventeen years.

B. As indicated above, due to the market requirements, there is probably no standard bow, therefore, no prices of such are given.

C. Wear strips for certain applications have to be made from stainless steel. Durability varies from user to user, but wear would be affected by the wire path of the various gauges of material being processed. Adjustments to tension would also have an effect on the durability of the wear strip.
We seem to continually end up in the position of being the "bow expert" when we neither use the bow in the normal operating environment of wire production, nor do our customers regularly provide us feedback concerning their operations for fear of losing a competitive advantage. We are the manufacturers of plastics which are reinforced with fibreglass, kevlar and carbon fibre and have through our customers gained a certain expertise at the speeds attained by and environments in which our bows are used. We do not however have all the answers, but strive to work together with producers to satisfy their individual needs.

Carbon fibre and GKC bows have a higher tensile strength than steel by weight (up to five times stronger). Therefore, the following savings may result:

A. There is less weight on the bearings, so replacement is less frequent resulting in cost savings in bearing purchases.

B. If the machine is overcome by the weight of moving parts then light weight plastic bows could result in higher RPM and therefore cost savings. The steel bows are much heavier in comparison.

C. When steel bows break during the operation, damage will often result to more than just the bow. The broken bow may damage the spool and the wire on it, other parts of the machine and possibly even the operator or others passing by at the time of the bow breakage.

D. Labour costs for broken bow removal are higher because the steel bows are harder to remove when wrapped around other machine parts.

E. Labour costs for machine maintenance are reduced with the reduction in bearing replacement.

F. Power consumption will reduce with the light weight plastic bows since there isn't as much weight to turn inside the machine resulting in savings in electricity costs.

G. Plastic bows will return to the original shape if bent where steel will not resulting in less changes having to be made.

H. Broken plastic bows clean up easier resulting in cost savings as well.

"Downtime" of one hour, two hours or perhaps a day results in no production of materials. This too is a cost added to the product.

Carbon fibre and GKC bows may appear more expensive at first, but many other savings should be considered before the decision to use steel bows is made.