Tolerance Chart
Threaded, Slip-On, Lap Joint, Socket Weld and Blind Flanges Tolerance
*Outside diameter	O.D. 500 or smaller		± 1.6
	O.D. over 600		± 3.1
Inside diameter	threaded	to standard gauge limits slip on: lap joint: socket welding
	250 and smaller	+ 0.7	− 0.0
	300 and largee	+ 1.6	− 0.0
diameter of counter bore	threaded
	250 and smaller	+ 0.7	− 0.0
	300 and large	+ 1.6	− 0.0
*Outside diameter of hub	300 and smaller	+ 2.3	− 1.6
	350 and larger		± 3.1
diameter of contract face	1.6 raised face		± 0.7
	6.3 raised face : tongue and grooved male and female		± 0.4
thickness	450 and smaller	+ 3.1	− 0.0
	500 and larger	+ 4.7	− 0.0
*length through hub	250 and smaller		± 1.6
	300 and larger		± 3.1
drilling	bolt circle		± 1.6
	bolt hole spacing		± 0.7
	eccenticity with respect of to bore		0.7 max

Tolerance Chart
Welding Neck Tolerance
*Outside diameter	O.D. 600 or smaller		± 1.6
	O.D. over 600		± 3.1
Inside diameter (bore)	250 and smaller		± 0.7
	12 through 450		± 1.6
	500 and larger	± 3.1	− 1.6
diameter of contact face	1.6 raised face	± 0.7
	6.3 raised face : tongue and grooved male and female	± 0.4
*diameter of hub at base	when E is 600 or smaller	± 1.6
	when E is over 600	± 3.1
diameter of hub at pointing of welding	125 and smaller	+ 0.7	± 0.7
	150 and larger	+ 0.4	± 0.0
thickness	450 and smaller	+ 3.1	− 0.0
	500 and larger	+ 4.7	− 0.0
length through hub	250 and smaller		± 1.6
	300 and larger		± 3.1
drilling	bolt circle		± 1.6
	bolt hale spacing		± 0.7
	eccentricity with respect to bore		0.7 max