Air/Vacuum Flow through an Orifice Table

Pressure Flow Through Orifices

Figures in body of chart are in air flows in SCFM (Standard cubic feet / minute)

Size Of Orifice (In.)	Pressure (psig)
	2	5	10	15	20	25	30	35	40	45	50	60	70	80	90	100	125	150	200
1/64″	.024	.040	.061	.079	.096	.113	.129	.145	.161	.177	.193	.225	.256	.287	.319	.350	.428	.506	.661
1/32″	.098	.161	.243	.319	.384	.451	.516	.581	.645	.709	.772	.898	1.02	1.15	1.27	1.40	1.71	2.02	2.64
3/64″	.22	.363	.547	.71	.86	1.01	1.16	1.31	1.45	1.59	1.74	2.02	2.30	2.59	2.87	3.15	3.85	4.55	5.95
1/16″	.391	.645	.972	1.26	1.54	1.80	2.07	2.32	2.58	2.84	3.09	3.59	4.10	4.60	5.10	5.60	6.85	8.09	10.6
3/32″	.881	1.45	2.19	2.84	3.46	4.06	4.65	5.23	5.81	6.38	6.95	8.09	9.22	10.3	11.5	12.6	15.4	18.2	23.8
1/8″	1.57	2.58	3.89	5.05	6.15	7.21	8.26	9.30	10.3	11.3	12.4	14.4	16.4	18.4	20.4	22.4	27.4	32.4	42.3
3/16″	3.52	5.80	8.75	11.4	13.8	16.2	18.6	20.9	23.2	25.5	27.8	32.3	36.9	41.4	45.9	50.4	61.6	72.8	95.2
1/4″	6.26	10.3	15.6	20.2	24.6	28.9	33.0	37.2	41.3	45.4	49.4	57.5	65.5	73.6	81.6	89.6	110	129	169
3/8″	14.1	23.2	35.0	45.4	55.3	64.9	74.4	83.7	92.9	102	111	129	147	166	184	202	246	291	381
1/2″	25.1	41.3	62.2	80.8	98.4	115	132	149	165	181	198	230	262	294	326	358	438	518	677
5/8″	39.1	64.5	97.2	126	154	180	207	232	258	284	309	359	410	460	510	560	685	809	1058
3/4″	56.4	92.9	140	182	221	260	297	335	372	408	445	518	590	662	734	806	986	1165	1523
7/8″	76.7	126	191	247	301	354	405	455	506	556	605	704	803	901	999	1097	1342	1586	2073
1″	100	165	249	323	393	462	529	595	661	726	791	920	1049	1177	1305	1433	1752	2071
1-1/8″	127	209	315	409	498	584	669	753	836	919	1001	1164	1327	1490	1652	1814	2218
1-1/4″	157	258	389	505	615	721	826	930	1032	1134	1236	1438	1639	1839	2039	2239
1-3/8″	189	312	471	611	744	893	1000	1125	1249	1372	1495	1739	1983	2226	2468
1-1/2″	225	371	560	727	885	1039	1190	1339	1486	1633	1779	2070	2360
1-3/4″	307	506	762	990	1205	1414	1619	1822	2023	2223	2422
2″	401	660	996	1293	1574	1847	2115	2380