---

Westfield Fasteners Product Specification:

DIN 80704 - Bow Nuts

This product guide contains the specification for metric threaded bow nuts, a range of standard parts available from Westfield Fasteners. The basis of this specification is the DIN standard DIN 80704.

Product Description

There are a number of different types of bow nuts available on the market today, and they are generally used to lift and secure loads. They are often employed in conjunction with a lifting eye bolt or hook. The standard for this particular type does not mention working load or breaking load limits, so are not recommended for hoisting or lifting operations. For this type of work we would recommend bow nuts with CE markings. These are usually produced in either self colour or zinc plated steel. This stainless steel design is traditionally used for hinge-type fastenings for windows on ships, but as an attractive fitting they can be used in any other application requiring a nice finish.

Scope of the DIN Standard.

The DIN standard 80704 defines the shape and dimensions for this type of bow nut. See figure 1 and table 1 below. The standard covers sizes M12, M16, M20 and M24, but other sizes are available. These extra sizes are therefore considered 'similar to' this standard and not in absolute accordance. DIN 80704 mentions material construction including aluminium alloy, cast iron and brass.

Figure 1: Bow Nut

Table 1: Dimensions & Tolerances according to DIN 80704 (mm)

Screw Thread, d1	a	b	c	d2	d3	d4	h	m
6	15	14	25	14	11.5	5	28	8
8	20	18	32	18	15	6.5	36	10
10	25	23	42	23	19	8	50	12
12	27	27	48	24	20	10	52	15
16	29	32	56	30	24	12	59	18
20	32	36	64	36	28	13	66	21
24	36	45	75	45	36	14	75	25

For verification of details and for further information please refer to the DIN standard document for this item. E&OE