ASME B16.9 Pipe Caps | McMaster-Carr

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119 Products

About Pipe and Fittings

Measure your pipe and fittings to identify their pipe size, thread size, schedule, and thread type. Then, find compatible components.

Fitting Type

Cap

Cover a pipe end to seal it

111 products

Plug

Insert into a pipe end to seal it

8 products

Performance

Chemical Resistant

Stay strong when exposed to acids, bases, and other harsh chemicals

72 products

Corrosion Resistant

Withstand exposure to moisture and mild chemicals

79 products

Low-Pressure Iron and Steel Butt-Weld Pipe Fittings

Butt-weld fittings allow for a smooth connection that provides maximum flow. They have beveled ends that, when flush to pipe, create a trough for a strong, permanent weld. Fittings are also known as Schedule 40. They are for use in noncorrosive environments.

Caps

Butt Weld

	Construction	OD	Pipe Schedule	Material		Each
Butt Weld



	1/2	Seamless	27/32"	40	Steel	43425K116	000000


	3/4	Seamless	1 3/64"	40	Steel	43425K126	00000
	1	Seamless	1 5/16"	40	Steel	43425K136	00000
	1 1/4	Seamless	1 21/32"	40	Steel	43425K146	00000
	1 1/2	Seamless	1 29/32"	40	Steel	43425K156	00000
	2	Seamless	2 3/8"	40	Steel	43425K166	00000
	2 1/2	Seamless	2 7/8"	40	Steel	43425K176	00000
	3	Seamless	3 1/2"	40	Steel	43425K186	00000
	4	Seamless	4 1/2"	40	Steel	43425K216	00000
	6	Seamless	6 5/8"	40	Steel	43425K236	00000
	8	Seamless	8 5/8"	40	Steel	43425K246	000000


	10	Seamless	10 3/4"	40	Steel	43425K256	000000

180° Bend Connectors

Image of Product. Front orientation. Pipe Traps. Low-Pressure Iron and Steel Butt-Weld Pipe Fittings.

180° bend connectors are also known as U-bends.

	Construction	Pipe Schedule	Material	Shape		Each
Butt Weld



	3/4	Seamless	40	Steel	180° Bend	43425K123	0000000


	1	Seamless	40	Steel	180° Bend	43425K133	000000
	1 1/4	Seamless	40	Steel	180° Bend	43425K143	000000
	1 1/2	Seamless	40	Steel	180° Bend	43425K153	000000
	2	Seamless	40	Steel	180° Bend	43425K163	000000
	2 1/2	Seamless	40	Steel	180° Bend	43425K173	000000
	3	Seamless	40	Steel	180° Bend	43425K183	000000
	4	Seamless	40	Steel	180° Bend	43425K213	000000
	6	Seamless	40	Steel	180° Bend	43425K233	000000

Stub-End Straight Adapters

Straight Adapter

Stub-end straight adapters are used with flanges. Slide a flange onto the stub end and weld the stub end to pipe (not the flange). Since the flange isn’t welded to the pipe, it can be disconnected easily, which creates an access point for frequent cleaning and inspecting.

Pipe Size	Flange OD	Construction	Pipe Schedule	Finished Material		Each
1/2	1 3/8"	Seamless	40	Steel	43425K115	000000
3/4	1 11/16"	Seamless	40	Steel	43425K125	00000
1	2"	Seamless	40	Steel	43425K135	00000
1 1/4	2 1/2"	Seamless	40	Steel	43425K145	000000
1 1/2	2 7/8"	Seamless	40	Steel	43425K155	000000
2	3 5/8"	Seamless	40	Steel	43425K165	000000
2 1/2	4 1/8"	Seamless	40	Steel	43425K175	000000
3	5"	Seamless	40	Steel	43425K185	000000
4	6 3/16"	Seamless	40	Steel	43425K215	000000
6	8 1/2"	Seamless	40	Steel	43425K235	000000
8	10 5/8"	Seamless	40	Steel	43425K245	000000

Medium-Pressure Stainless Steel Butt-Weld Pipe Fittings

Also known as Schedule 40 fittings, these have thicker walls than our thin-wall stainless steel unthreaded butt-weld fittings. They have beveled ends that, when flush to pipe, create a trough for a strong weld that permits maximum flow.

Caps

Butt Weld

304/304L Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.

316/316L Stainless Steel—Fittings are the most corrosion resistant. They stand up to wet environments, just like 304 stainless steel fittings, but unlike 304 stainless steel, they will not corrode from salt water, chlorine solutions, and chemicals.

					304/304L Stainless Steel		316/316L Stainless Steel
	Pipe Size	Construction	OD	Pipe Schedule		Each		Each
Butt Weld



		1/2	Welded	27/32"	40	45605K581	000000	45555K581	000000


		3/4	Welded	1 3/64"	40	45605K582	00000	45555K582	00000
		1	Welded	1 5/16"	40	45605K583	00000	45555K583	00000
		1 1/4	Welded	1 21/32"	40	45605K584	00000	45555K584	00000
		1 1/2	Welded	1 29/32"	40	45605K585	00000	45555K585	00000
		2	Welded	2 3/8"	40	45605K586	00000	45555K586	00000
		2 1/2	Welded	2 7/8"	40	45605K587	00000	45555K587	00000
		3	Welded	3 1/2"	40	45605K591	00000	45555K591	00000
		4	Welded	4 1/2"	40	45605K593	00000	45555K593	00000
		6	Welded	6 5/8"	40	45605K595	00000	45555K595	000000
		8	Welded	8 5/8"	40	45605K529	000000	45555K614	000000

Stub-End Straight Adapters

Straight Adapter

					316/316L Stainless Steel
Pipe Size	Wall Thk.	Flange OD	Construction	Pipe Schedule		Each
1/2	0.109"	1 3/8"	Welded	40	45555K651	000000
3/4	0.113"	1 11/16"	Welded	40	45555K652	00000
1	0.133"	2"	Welded	40	45555K653	00000
1 1/4	0.14"	2 1/2"	Welded	40	45555K654	00000
1 1/2	0.145"	2 7/8"	Welded	40	45555K655	00000
2	0.154"	3 5/8"	Welded	40	45555K656	00000
2 1/2	0.203"	4 1/8"	Welded	40	45555K657	00000
3	0.216"	5"	Welded	40	45555K661	00000
4	0.237"	6 3/16"	Welded	40	45555K663	00000
6	0.28"	8 1/2"	Welded	40	45555K665	000000
8	0.322"	10 5/8"	Welded	40	45555K615	000000

Low-Pressure Stainless Steel Butt-Weld Pipe Fittings

Also known as Schedule 10 fittings, these are thin and lightweight. They have beveled ends that, when flush to pipe, create a trough for a strong weld that permits maximum flow.

Caps

Butt Weld

304/304L Stainless Steel—Fittings hold up in humid, damp, and washdown environments but will corrode if exposed to salt water or chemicals.

					304/304L Stainless Steel		316/316L Stainless Steel
	Pipe Size	Construction	OD	Pipe Schedule		Each		Each
Butt Weld



		1/2	Welded	27/32"	10	45735K271	000000	43645K371	000000


		3/4	Welded	1 3/64"	10	45735K272	00000	43645K372	00000
		1	Welded	1 5/16"	10	45735K273	00000	43645K373	00000
		1 1/4	Welded	1 21/32"	10	45735K277	00000	43645K147	00000
		1 1/2	Welded	1 29/32"	10	45735K275	00000	43645K375	00000
		2	Welded	2 3/8"	10	45735K276	00000	43645K376	00000
		2 1/2	Welded	2 7/8"	10	45735K281	00000	43645K148	00000
		3	Welded	3 1/2"	10	45735K278	00000	43645K378	00000
		4	Welded	4 1/2"	10	45735K279	00000	43645K379	00000
		6	Welded	6 5/8"	10	45735K282	00000	43645K149	00000
		8	Welded	8 5/8"	10	45735K115	000000	43645K151	000000


		10	Welded	10 3/4"	10	45735K619	000000	43645K458	000000
		12	Welded	12 3/4"	10	45735K621	000000	43645K459	000000

Stub-End Straight Adapters

Straight Adapter

					304/304L Stainless Steel		316/316L Stainless Steel
Pipe Size	Wall Thk.	Flange OD	Construction	Pipe Schedule		Each		Each
1/2	0.083"	1 3/8"	Welded	10	———	0	43645K391	000000
3/4	0.083"	1 11/16"	Welded	10	———	0	43645K392	00000
1	0.109"	2"	Welded	10	———	0	43645K393	00000
1 1/4	0.109"	2 1/2"	Welded	10	———	0	43645K152	00000
1 1/2	0.109"	2 7/8"	Welded	10	———	0	43645K395	00000
2	0.109"	3 5/8"	Welded	10	———	0	43645K396	00000
2 1/2	0.12"	4 1/8"	Welded	10	———	0	43645K153	00000
3	0.12"	5"	Welded	10	———	0	43645K398	00000
4	0.12"	6 3/16"	Welded	10	———	0	43645K399	00000
6	0.134"	8 1/2"	Welded	10	———	0	43645K154	000000
8	0.148"	10 5/8"	Welded	10	———	0	43645K155	000000
10	0.134"	12 3/4"	Welded	10	45735K622	0000000	———	0
12	—	15"	Welded	10	———	0	43645K462	000000

Medium-Pressure Aluminum Butt-Weld Pipe Fittings

Also known as Schedule 40 fittings, these have thicker walls than our thin-wall aluminum unthreaded pipe fittings. They have beveled ends that, when flush to pipe, create a trough for a strong weld that permits maximum flow. Fittings are lightweight with good corrosion resistance.

Caps

Butt Weld

	Construction	OD	Pipe Schedule	Material		Each
Butt Weld



	1	Seamless	1 5/16"	40	6061 Aluminum	43485K192	0000000


	1 1/4	Seamless	1 21/32"	40	6061 Aluminum	43485K193	000000
	1 1/2	Seamless	1 29/32"	40	6061 Aluminum	43485K194	000000
	2	Seamless	2 3/8"	40	6061 Aluminum	43485K195	000000
	2 1/2	Seamless	2 7/8"	40	6061 Aluminum	43485K196	000000
	3	Seamless	3 1/2"	40	6061 Aluminum	43485K197	000000
	4	Seamless	4 1/2"	40	6061 Aluminum	43485K201	000000

Medium-Pressure Stainless Steel Threaded Pipe Fittings

Choose these fittings when you want the same high-quality found in our low-pressure pipe fittings, but need more strength to handle higher pressures.

External-Hex-Drive Plugs

Male

Alloy 20 Stainless Steel—These fittings have the best corrosion resistance of all the stainless steel fittings we offer. Alloy 20 stainless steel is also known as Carpenter 20 and resists cracking from stress and corrosion.

					Alloy 20 Stainless Steel
	Pipe Size	Construction	Pressure Class	Body Shape		Each
NPT Male



		1/8	Solid	Not Rated	Hex	2698K214	0000000


		1/4	Solid	Not Rated	Hex	2698K215	000000
		3/8	Solid	Not Rated	Hex	2698K216	000000
		1/2	Solid	Not Rated	Hex	2698K211	000000
		3/4	Solid	Not Rated	Hex	2698K212	000000
		1	Solid	Not Rated	Hex	2698K213	000000
		1 1/2	Solid	Not Rated	Hex	2698K217	000000
		2	Solid	Not Rated	Hex	2698K218	000000