Spacer & Blind Flanges | ASME B16.48 | Line Blanks

Spacer blinds, also called line spacers or paddle spacers, are piping components built to manage flow isolation during maintenance, inspection, and shutdowns. They work as a pair with a companion line blind, or paddle blind. A spacer blind is a solid metal ring with an open bore that matches the inside diameter of the pipeline, fitted with a long handle, or paddle, that sticks out past the flange. When the system is running normally, the spacer blind is bolted between two flanges, filling the gap and leaving a clear, full-bore path for the fluid. That flush bore keeps the flow smooth, holds pressure drop down, and stops product from building up or eating away at the flange faces. PM Industries manufactures, supplies, and stocks spacer blinds in a wide range of grades, sizes, and pressure classes.

The build of a spacer blind has to take real punishment. We forge or machine them from carbon steel, stainless steel, alloy steel, and nickel-base superalloys to standards such as ASME B16.48, then heat treat them for dimensional stability. When a section needs full isolation for hazardous work, technicians loosen the flange bolts, pull the spacer blind, and slide a solid paddle blind into its place for a positive, zero-leakage shutoff. The external handle does important work here. It stays visible outside the insulation or jacket, usually stamped with material grade, pressure rating, and size, so operators can tell at a glance whether the line is open or blinded. That simple visual check is a safety feature in its own right.

Because they keep the line safe and the fluid contained during turnarounds, spacer blinds earn their place across demanding sectors. You will find them in petroleum refineries, chemical plants, offshore platforms, and thermal power stations, isolating pipelines, valves, pumps, and pressure vessels. They prove their worth on high-pressure steam loops, toxic chemical conduits, and heavy hydrocarbon lines, where containment has to stay absolute to protect people and equipment.

PM Industries holds a deep stock of spacer blinds across pressure classes from 150 to 2500, with raised face (RF) and ring-type joint (RTJ) sealing faces. Every unit ships with certification and test documentation to match your project spec. Tell us your size, class, face type, and material, and we will quote it.

Specification Spectacle/Spacer Blinds

Standards	ANSI/ASME B16.5, B16.48, GOST, DIN, EN-1092, B16.47 Series A & B, AWWA, BS Flanges
JIS Standard	5K, 10K, 16K, 20K, 30K, 40K, 63K
DIN Flanges	DIN 2527, 2627, 2631, 2656, 2576, 2673, 2629, 2628, 2566

Flanges are Available in Following Materials

Stainless Steel	SS 201, SS 202, SS 301, SS 304, SS 304L, SS 310, SS 310S, SS 316L, SS 316TI, SS 317, SS 317L, SS 321, SS 347, SS 409, SS 409M, SS 409L, SS 410, SS 410S, SS 420, SS 430, SS 431, SS 441, SS 444, SS 446, SS 17-4PH, SS 904L.
Duplex Steel	UNS S32205, UNS S31803 Flange
Super Duplex Steel	UNS S32750, UNS S32760 Flanges
Carbon Steel	Carbon steel A105 Flanges, A36 Flanges, IS 2062 Flanges, A350 LF2 Flanges, F42 Flanges, F52 Flanges, F56 Flanges, F60 Flanges, F65 Flanges, F70 Flanges, F80 Flanges, IBR flanges, A694 Flanges, SS400, SF440, ST37-2 Flanges, S235JrG2 Flanges, P250GH Flanges, C22.8 Flanges, etc.
Alloys Steel	Alloy 20, F1, F5, F9, F11, F22, F91 Flanges
Copper Alloys	Cu-Ni 70/30, Cu-Ni 90/10, C 24000, C 75700, C 51100, C 22000, C 27200, C 21000, C 26800, C 52100, C 77000, C 52000, C 11000, C 74500, C 23000, C 28000, C 12200, C 76400, C 51900, C 75400, C 26000, C 51000, C 10200, C 27000
Nickel Alloys	Nickel 200, 201
Inconel	Inconel 600, 601, 625, 718, 800, 825, X-750
Monel	Monel 400, k500
Hastelloy	Hastelloy C-22, C-276, C-4, X
Titanium	Grade 1, 4, 5(Ti 6Al-4V), 6(Ti 5Al-2.5Sn), 7, 11, 6Al-2Sn-4Zr-2Mo, Grade 12, 6Al-6V-25n, Grade 23(Ti 6AL-4V ELI), 8Ai-1Mo-1V, Grade 5 ELI, Grade 9(3Al-2.5V), 6Al-7Nb.
Aluminium	6063, 1100, 6082 A96082, 1050, 2017, 2024 A92024, 7050 A97050, 5083 A95083, 2014A A92014, 2011 A92011, 6061 A96061 A86061, 5754, 7085, 2050, 7071 7020, 7178, 5052 A95052, 7150, 7075 A97075 A87075, 7575, 2219, 7175
Pressure Rating	Class 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS
Types	Threaded, Plate, Screwed, Forged.
Supporting material	Gasket, Ring Joint, Flange Bolts
Size range	1/2" (15 NB) to 48" (1200NB) DN10~DN5000
High Temperature	Above 200°C (400°F) For Class 150 Or Above 400°C (750°F)
Low Temperature	Above -29 Degree C (−20°F)
Production technique	Forged, machined and Heat treated
Custom design	As per your drawing
Origin	Indian / USA / Korean / West Europe / Japan
Pressure Class	PN 6 TO PN 100
Coating/Surface Treatment:	Zinc Plated, Anti-rust Paint, Oil Black Paint, Yellow Transparent, Cold and Hot Dip Galvanized.
European/African/Russian Standard Flanges	Available
Test	Direct-reading Spectrograph, X-ray detector, UItrasonic flaw detector, Magnetic particle detector, Hydrostatic testing machine.
Marking Standard	Name of Manufacturer
	Schedule
	Type of Flange Facing
	Pressure Class
	Nominal Pipe Size, etc
Test Certificates	EN 10204/3.1B, NACE MR0103, NACE MR0175
	Raw Materials Certificate
	100% Radiography Test Report
	Third Party Inspection Report, etc

CLASS 150 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 150	A	B	C	t	W
1/2	45	16	60	3	38
3/4	54	21	70	3	38
1	64	27	80	3	38
1¼	73	42	90	6.4	38
1½	83	48	100	6.4	38
2	102	61	120	6.4	51
2½	107	73	140	6.4	51
3	133	89	150	6.4	64
3½	159	102	175	9.7	64
4	172	114	190	9.7	64
5	194	141	215	9.7	76
6	219	168	240	12.7	76
8	276	219	300	12.7	76
10	337	273	360	15.7	102
12	406	324	430	19.1	102
14	448	356	475	19.1	108
16	511	406	460	22.4	108
18	546	457	580	25.4	114
20	603	508	635	28.4	121
24	714	610	750	31.8	140

CLASS 300 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 300	A	B	C	t	W
1/2	51	16	65	6.4	38
3/4	64	21	80	6.4	38
1	70	27	90	6.4	38
1¼	79	42	100	6.4	38
1½	92	48	115	6.4	38
2	108	61	125	9.7	51
2½	127	73	150	9.7	51
3	146	89	170	9.7	64
3½	162	102	185	12.7	64
4	178	114	200	12.7	64
5	213	141	235	15.7	76
6	248	168	270	15.7	76
8	305	219	330	22.4	76
10	359	273	385	25.4	102
12	419	324	450	28.4	102
14	483	356	515	31.8	108
16	536	406	570	38.1	108
18	594	457	630	41.1	114
20	651	508	685	44.5	121
24	772	610	810	50.8	140

CLASS 600 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 600	A	B	C	t	W
1/2	51	16	65	6.4	38
3/4	64	21	80	6.4	38
1	70	27	90	6.4	57
1¼	79	37	100	9.7	57
1½	92	43	115	9.7	67
2	108	55	125	9.7	57
2½	127	67	150	12.7	67
3	146	83	170	12.7	67
3½	159	96	185	15.7	76
4	191	108	215	15.7	76
5	238	135	265	19.1	86
6	264	162	290	22.4	86
8	318	212	350	28.4	95
10	397	265	430	35.1	105
12	454	315	490	41.1	105
14	489	346	525	44.5	114
16	562	397	605	50.8	124
18	610	448	655	53.8	133
20	679	497	725	63.5	133
24	787	597	840	73.2	152

CLASS 900 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 900	A	B	C	t	W
1/2	60	16	80	6.4	38
3/4	67	21	90	6.4	41
1	76	27	100	6.4	57
1¼	86	37	110	9.7	57
1½	95	43	125	9.7	67
2	140	55	165	12.7	57
2½	162	67	190	12.7	67
3	165	83	190	15.7	67
4	203	108	235	19.1	76
5	244	135	280	22.4	86
6	286	162	320	25.4	86
8	356	212	395	35.1	95
10	432	265	470	41.1	105
12	495	315	535	47.8	105
14	518	346	560	53.8	114
16	572	397	615	60.5	124
18	635	448	685	66.5	133
20	696	497	750	73.2	133
24	835	597	900	88.9	152

CLASS 1500 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 1500	A	B	C	t	W
1/2	61	16	80	6.4	38
3/4	67	21	90	9.7	41
1	76	27	100	9.7	64
1¼	86	35	110	9.7	64
1½	95	41	125	12.7	70
2	140	53	165	12.7	70
2½	162	63	190	15.7	76
3	172	78	205	19.1	76
4	206	102	240	22.4	89
5	251	128	290	28.4	89
6	279	154	320	35.1	89
8	349	203	395	41.1	102
10	432	255	480	50.8	114
12	518	303	570	60.5	114
14	575	333	635	66.5	127
16	638	381	705	76.2	133
18	702	429	775	85.9	146
20	752	478	830	95.3	152
24	899	575	990	111.3	178

CLASS 2500 Spectacle Blind Dimensions ASME B16.48

Spectacle Blind NPS Dimensions Class 2500	A	B	C	t	W
1/2	67	16	90	9.7	38
3/4	73	21	95	9.7	41
1	83	27	110	9.7	64
1¼	102	35	130	12.7	64
1½	114	41	145	15.7	70
2	143	53	170	15.7	70
2½	165	63	195	19.1	76
3	194	78	230	22.4	76
4	232	102	275	28.4	89
5	276	128	325	35.1	89
6	314	154	370	41.1	89
8	384	198	440	53.8	102
10	473	248	540	66.5	114
12	546	289	620	79.2	114