Nominal internal diameter	Internal diameter	External diameter	L	a	Number of holes per piece			water inlet area	Safe crushing strength
					Z1	Z2	Total holes Z
			+/-2%
DN	d1	d3
mm	mm	mm	mm	mm	nos.	nos.	nos.	mm2/m	kN/m
100	100+/-3	131+/-3	1000	10	8	16	128	10053	28
150	151+/-5	186+/-4	1500	10	8	16	128	6702	28
					12	16	192	10053
200	202+/-5	242+/-5	1500	10	8	16	128	6702	28
					12	16	192	10053
200	202+/-5	242+/-5	1750	10	8	19	152	7958	28
					12	19	228	10232
250	252+/-6	296+/-6	2000	10	8	22	176	6912	30
					12	22	264	10367
300	302+/-7	351+/-7	2000	10	8	22	176	6912	34
					12	22	264	10367
400	402+/-8	460+/-8	2000	10	8	22	176	6912	44
					12	22	264	10367
500	496+/-9	581+/-9	2000	10	8	22	176	6912	60
					12	22	264	10367
600	603+/-12	721+/-12	2000	10	8	22	176	6912	70
					12	22	264	10367
700	704+/-15	831+/-15	2000	10	8	22	176	6912	81
					12	22	264	10367
Note:    a = diamaeter of hole      Z1 = no. of holes per piece (radial)       Z2 = no. of holes per piece (longitudinal)
8mm, 12mm & 13mm diameter holes available on request