Armstrong DS Series drain separators efficiently separate condensate by using the centrifugal force of steam or air created by introducing it into a specifically shaped path. Condensate in steam and air piping reduces thermal efficiency, causes water hammer, corrodes equipment such as valves and pipes, and causes other problems. Because of the simple structure of the drain separators, pressure loss is minimized, enabling clean, dry steam or air to be fed to equipment.

With correct sizing and proper drainage, the separators are designed to eliminate 98% of all entrained liquids and particles that are 10 microns and larger in size.

Features

• A cyclone structure maximizes liquid separation efficiency
• Pressure loss is extremely low
• No moving parts means no breakdowns

Operating Principle

When steam or air flow enters the drain separator, centrifugal force is generated in the fluid because of the device’s internal structural design. The fluid drains along the wall because of the difference in specific gravity with steam or air, eventually striking the baffle. The baffle guides the fluid to the drain outlet and to the trap, which drains it. As a result, both small dirt particles and condensate are separated and removed from the system through the bottom drain.

Specifications

Model	Application	Maximum Pressure	Maximum Temp.	Body Material	Nozzle Material
DS-1	Steam / Air	NPT 300 psig (20 barg)	430°F (221°C)	Ductile Iron ASTM A536	Cast Iron ASTM A48
DS-2	Steam / Air	150 lb. Flanged 185 psig (13 barg) 300 lb. Flanged 300 psig (20 barg)	430°F (221°C)	Ductile Iron ASTM A536	Cast Iron ASTM A48
DS-3	Steam / Air	NPT 300 psig (20 barg) 150 lb. Flanged 150 psig (10 barg) 300 lb. Flanged 500 psig (34 barg)	650°F (343°C) 450°F (232°C) 650°F (343°C)	SS304	SS304
DS-4	Steam / Air	NPT 300 psig (20 barg) 150 lb. Flanged 150 psig (10 barg) 300 lb. Flanged 500 psig (34 barg)	650°F (343°C) 450°F (232°C) 650°F (343°C)	Carbon Steel	Carbon Steel

Dimensions and Weights

Model	Size	L (NPT)	L (150#)	L (300#)	H	H1	Drain	Weight (NPT)	Weight (150#)	Weight (300#)
DS-1	1/2" (15mm)	5-15/16" (150mm)	—	—	9-9/16" (243mm)	7-5/8" (193mm)	3/4" (20mm)	16 lb (7.3 kg)	—	—
DS-1	3/4" (20mm)	5-15/16" (150mm)	—	—	9-9/16" (243mm)	7-5/8" (193mm)	3/4" (20mm)	16 lb (7.3 kg)	—	—
DS-1	1" (25mm)	5-15/16" (150mm)	—	—	9-9/16" (243mm)	7-5/8" (193mm)	3/4" (20mm)	16 lb (7.3 kg)	—	—
DS-1	1-1/4" (32mm)	7-1/2" (190mm)	—	—	11-1/8" (243mm)	8-3/8" (213mm)	1" (25mm)	28 lb (12.7 kg)	—	—
DS-1	1-1/2" (40mm)	7-1/2" (190mm)	—	—	11-1/8" (243mm)	8-3/8" (213mm)	1" (25mm)	28 lb (12.7 kg)	—	—
DS-1	2" (50mm)	8-5/8" (219mm)	—	—	13-15/32" (243mm)	10-1/4" (260mm)	1" (25mm)	45 lb (20.5 kg)	—	—
DS-2	2-1/2" (65mm)	—	11-1/2" (292mm)	11-15/16" (303mm)	16-15/32" (418mm)	12-3/8" (314mm)	1" (25mm)	—	45 lb (20.5 kg)	77 lb (35 kg)
DS-2	3" (80mm)	—	13-1/2" (343mm)	14-1/64" (356mm)	19" (484mm)	14-1/2" (361mm)	1-1/4" (32mm)	—	77 lb (35 kg)	99 lb (45 kg)
DS-2	4" (100mm)	—	15-13/16" (402mm)	16-7/16" (418mm)	23-3/8" (594mm)	17-1/2" (445mm)	1-1/4" (32mm)	—	99 lb (45 kg)	143 lb (65 kg)
DS-3	1/2" (15mm)	5-1/2" (140mm)	9" (229mm)	9" (229mm)	16" (356mm)	9" (229mm)	1" (25mm)	28 lb (12.7 kg)	30 lb (13.6 kg)	32 lb (14.5 kg)
DS-3	3/4" (20mm)	5-1/2" (140mm)	9" (229mm)	9" (229mm)	16" (356mm)	9" (229mm)	1" (25mm)	28 lb (12.7 kg)	30 lb (13.6 kg)	32 lb (14.5 kg)
DS-3	1" (25mm)	6-3/8" (162mm)	10-1/2" (267mm)	10-1/2" (267mm)	16" (356mm)	10-1/2" (267mm)	1" (25mm)	30 lb (13.6 kg)	33 lb (15 kg)	35 lb (15.9 kg)
DS-3	1-1/4" (32mm)	6-3/8" (162mm)	10-1/2" (267mm)	10-1/2" (267mm)	16" (356mm)	10-1/2" (267mm)	1" (25mm)	32 lb (14.5 kg)	35 lb (15.9 kg)	37 lb (16.8 kg)
DS-3	1-1/2" (40mm)	7-5/8" (194mm)	11-1/2" (292mm)	11-1/2" (292mm)	19" (483mm)	12-1/2" (318mm)	1" (25mm)	46 lb (20.9 kg)	50 lb (22.7 kg)	56 lb (25.4 kg)
DS-3	2" (50mm)	7-7/8" (200mm)	11-1/2" (292mm)	11-1/2" (292mm)	19" (483mm)	12-1/2" (318mm)	1" (25mm)	51 lb (23.1 kg)	55 lb (24.9 kg)	59 lb (26.8 kg)
DS-3	2-1/2" (65mm)	—	16" (406mm)	16" (406mm)	22" (559mm)	15" (381mm)	1" (25mm)	—	100 lb (45.4 kg)	110 lb (49.9 kg)
DS-4	3" (80mm)	—	18" (457mm)	18" (457mm)	26" (660mm)	18" (457mm)	1" (25mm)	—	140 lb (63.5 kg)	150 lb (68 kg)
DS-4	4" (100mm)	—	20" (508mm)	20" (508mm)	31" (787mm)	22" (559mm)	1-1/2" (40mm)	—	195 lb (88.4 kg)	220 lb (99.8 kg)
DS-4	6" (150mm)	—	24" (610mm)	24" (610mm)	41" (1041mm)	30" (762mm)	1-1/2" (40mm)	—	350 lb (159 kg)	380 lb (172 kg)
DS-4	8" (200mm)	—	28" (711mm)	28" (711mm)	50" (1270mm)	37" (940mm)	2" (50mm)	—	475 lb (215 kg)	610 lb (278 kg)
DS-4	10" (250mm)	—	34" (864mm)	34" (864mm)	70" (1778mm)	55" (1397mm)	2" (50mm)	—	780 lb (354 kg)	1180 lb (535 kg)
DS-4	12" (300mm)	—	38" (965mm)	38" (965mm)	75" (1905mm)	58" (1473mm)	2-1/2" (65mm)	—	940 lb (426 kg)	1510 lb (685 kg)

Capacities for Steam Service

DS-1 / DS-2 Series Steam Capacities (lb/hr)

Size	5 psig	10 psig	25 psig	50 psig	100 psig	150 psig	200 psig	250 psig	300 psig
1/2”	34	43	69	113	200	287	374	461	548
3/4”	60	75	121	198	351	503	656	809	962
1”	98	122	197	320	568	816	1 063	1 311	1 559
1-1/4”	169	212	340	555	983	1 412	1 840	2 269	2 698
1-1/2”	230	288	463	755	1 338	1 922	2 505	3 088	3 672
2”	379	475	763	1 244	2 206	3 167	4 129	5 090	6 052
2-1/2”	541	678	1 089	1 775	3 147	4 519	5 891	7 263	8 635
3”	835	1 046	1 682	2 741	4 860	6 978	9 096	11 215	13 333
4”	1 437	1 802	2 896	4 720	8 368	12 016	15 664	19 312	22 960

DS-3 / DS-4 Series Steam Capacities (kg/hr)

Size	0.34 barg	0.69 barg	1.7 barg	3.4 barg	6.9 barg	10.3 barg	13.8 barg	17.2 barg	20.7 barg
1"	86	102	134	177	249	306	354	390	454
1-1/4"	145	156	209	281	390	476	510	517	526
1-1/2"	209	227	308	399	556	703	816	907	1 021
2"	358	413	476	703	998	1 225	1 429	1 678	1 814
2-1/2"	488	508	719	1 089	1 542	1 950	2 268	2 438	2 903
3"	885	1 043	1 338	1 701	2 381	2 994	3 447	4 082	4 536
4"	1 474	1 724	2 257	2 767	4 082	5 035	5 897	5 216	5 284
5"	2 257	2 654	3 470	4 196	5 171	5 307	5 443	10 433	11 340
6"	3 943	4 078	4 581	4 740	9 752	12 020	14 061	16 329	17 690
8"	4 876	5 194	5 443	10 773	15 422	19 504	23 133	26 308	29 937
10"	9 072	10 206	13 381	16 783	24 721	30 844	35 380	40 823	45 359
12"	13 381	15 422	19 958	24 494	36 741	45 359	47 627	50 802	51 710

Installation and Start-up

Installation Note

No special start-up or shut-down procedure is needed. Make sure that the separator is drained by a steam trap or a liquid drainer as shown below. The installation shown is for steam applications. For air, the steam trap draining the separator should be replaced by a liquid drainer.