Minimum Pipe Spacing Chart

In petrochemical & refinery plants there are many pipes which are running from source to destination. In most of the cases there is pipe rack between the plant units which carry these pipes and distribute it across the plant. When the pipes are running next to each other there should be some minimum spacing between the pipes so that there shall be no clash between the pipes during construction.

The basic principle for spacing the pipes adjacent to each other is:

Centre to centre between the pipes = half O/D (outside diameter) of the bigger size pipe flange + Insulation thickness of bigger size pipe (if applicable) + 25mm + half O/D (outside diameter) of the smaller size pipe + Insulation thickness of smaller size pipe(if applicable).

PIPE  SIZE	NOMINAL PIPE SIZE ( Millimeters ) AND FLANGE RATING
	400			450			500			550			600
	150#	300#	600#	150#	300#	600#	150#	300#	600#	150#	300#	600#	150#	300#	600#
25	345	370	395	370	405	420	395	430	460	420	470	485	460	510	520
40	355	380	395	370	405	430	405	445	460	430	470	495	460	510	520
50	355	380	405	380	420	430	405	445	470	430	485	495	470	520	535
80	370	395	420	395	430	445	420	460	485	445	495	510	485	535	545
100	380	405	430	405	445	460	430	470	495	460	510	520	495	545	560
150	420	445	460	430	470	485	470	510	520	495	535	545	520	570	585
200	445	470	485	460	495	510	495	535	545	520	560	570	545	595	610
250	470	495	510	485	520	535	520	560	570	545	585	595	570	625	635
300	495	520	535	510	545	560	545	585	595	570	610	625	595	650	660
350	510	535	545	520	560	585	560	595	610	585	625	650	610	660	675
400	535	560	570	545	585	610	585	625	635	610	650	675	635	685	700
450	560	585	595	570	610	635	610	650	660	635	675	700	660	710	725
500	585	610	625	595	635	660	635	675	685	660	700	725	685	735	750
550	610	635	650	625	660	685	660	700	710	685	725	750	710	760	775
600	635	660	675	650	685	710	685	725	735	710	750	775	735	790	800
650	660	685	700	675	710	735	710	750	760	735	775	800	760	815	825
700	685	710	725	700	735	760	735	775	790	760	800	825	790	840	850
750	710	735	750	725	760	790	760	800	815	790	825	850	815	865	875
800	735	760	775	750	790	815	790	825	840	815	850	875	840	890	900
850	760	790	800	775	815	840	815	850	865	840	875	900	865	915	930
900	790	815	825	800	840	865	840	875	890	865	900	930	890	940	955
1050	865	890	900	875	915	940	915	955	965	940	980	1005	965	1015	1030

PIPE  SIZE	NOMINAL PIPE SIZE ( Millimetres ) AND FLANGE RATING
	650			700			750			800			850
	150 #	300 #	600 #	150 #	300 #	600 #	150 #	300 #	600 #	150 #	300 #	600 #	150 #	300 #	600 #
25	485	535	560	510	570	585	545	595	610	585	625	650	610	650	675
40	495	545	560	520	570	595	545	595	625	585	635	650	610	660	675
50	495	545	570	520	585	595	560	610	625	595	635	660	625	660	685
80	510	560	585	535	595	610	570	625	635	610	650	675	635	675	700
100	520	570	595	545	610	625	585	635	650	625	660	685	650	685	710
150	545	595	625	585	635	650	610	660	685	650	685	710	675	725	735
200	570	625	650	610	660	675	635	685	710	675	710	735	700	750	760
250	595	650	675	635	685	700	660	710	735	700	735	760	725	775	790
300	625	675	700	660	710	725	685	735	760	725	760	790	750	800	815
350	650	700	710	675	725	750	700	750	775	735	790	800	760	815	825
400	675	725	735	700	750	775	725	775	800	760	815	825	790	840	850
450	700	750	760	725	775	800	750	800	825	790	840	850	815	865	875
500	725	775	790	750	800	825	775	825	850	825	865	875	840	890	900
550	750	800	815	775	825	850	800	850	875	840	890	900	865	915	930
600	775	825	840	800	850	875	825	875	900	865	915	930	890	940	955
650	800	850	865	825	875	900	850	900	930	890	940	955	915	965	980
700	825	875	890	850	900	930	875	930	955	915	965	980	940	990	1005
750	850	900	915	875	930	955	900	955	980	940	990	1005	965	1015	1030
800	875	930	940	900	955	980	930	980	1005	965	1015	1030	990	1040	1055
850	900	955	965	930	980	1005	955	1005	1030	990	1040	1055	1015	1065	1080
900	930	980	990	955	1005	1030	980	1030	1055	1015	1065	1080	1040	1095	1105
1050	1005	1055	1065	1030	1080	1105	1055	1105	1130	1095	1145	1155	1120	1170	1180