Double Suction Split-Case Pump — SOM Series

SOM single-stage double-suction split-case pump: flow 74–23500 m³/h, head 7–306 m, power 15–2500 kW, 720/990/1480/2990 r/min.

SOM horizontally split double suction pump

Double suction pump with split casing, on white background

Double suction pump viewed from the top cover, on white background

Double suction pump with large-bore suction flange, on white background

Double suction pump coupled to its drive motor, on white background

Double suction pump set with belt guard and motor, on white background

SOM horizontally split double-suction pump — the casing splits along the shaft axis, so the whole rotating assembly lifts out with the suction and discharge pipework left bolted in place.

Flow coverage 74–23,500 m³/h; design conforms to GB/T5657
Double suction cancels axial hydraulic load — bearings carry radial load only
Fully enclosed shaft never contacts the medium, so it does not corrode
Short bearing span raises shaft stiffness and limits vibration
Resin sand moulding holds passage form; CFD-optimised hydraulics
Mechanical or packing seal; stainless or treated shaft sleeves

Request SOM Specs →Send Us Your Flow & Head

CE · EAC · ISO 9001 · ISO 14001 · ISO 45001

Overview

The SOM series is a horizontally split, single-stage, double-suction centrifugal pump. Because the casing splits along the shaft axis, the entire rotating assembly can be lifted out by removing the top half — the suction and discharge pipework stays bolted in place. On a duty that runs continuously and is inspected on a schedule, that single feature usually decides the pump choice.

The design conforms to GB/T5657. It handles clean water and media of similar physical properties; by changing wet-end material and sealing arrangement it can be built for other liquids, which should be specified at enquiry.

Working conditions

Inlet / outlet diameter	150–1600 mm (flange dimensions to GB/1724.16-2022)
Flow range	74–23,500 m³/h
Speed	720, 990, 1480 and 2960 r/min
Power	15–2500 kW
Temperature conditions	Liquid maximum temperature ≤ 80 °C (to 120 °C on request); ambient temperature generally ≤ 40 °C
Maximum working pressure	Inlet pressure + pumping pressure: 1.0 MPa(G) for Hsp ≤ 75 m, or 1.6 MPa(G) for Hsp > 75 m. Special configuration to 1.6 MPa(G) or 2.5 MPa(G)
Medium	Clean water, or a liquid similar in physical and chemical properties to clean water
Material	Cast iron, or stainless steel SS304 / SS316 / SS316L
Sealing water pipe component	Inlet pressure < 0.3 MPa(G) — equipment not required
Structural design	Single-stage double-suction split-casing centrifugal pump, horizontally mounted. The driver (electric motor or internal combustion engine) can be set to the left or right of the pump as required — facing the outlet, the driver rotates counter-clockwise on the left side and clockwise on the right side

Model designation

Example: 500-SOM-35 A

500	Inlet diameter in millimetres
SOM	Pump model
35	Pump design point head, m
A	First cut of impeller

Why Double Suction

Liquid enters the impeller from both sides, so the axial hydraulic loads oppose and largely cancel. The bearings then carry radial load only, and the pump handles high flow at moderate head without the axial thrust that limits a single-suction machine of the same capacity. Flow coverage across the series runs from 74 to 23,500 m³/h.

Construction

Straight-line casing with reinforcing ribs — gives a stable mounting and a rational load path through the casing.
Short bearing span — raises shaft stiffness, which is what keeps vibration and noise low at speed.
Fully enclosed shaft design — the shaft does not contact the pumped medium, so it does not corrode and remains easy to dismantle. This is the reason the shaft is normally reusable at overhaul.
Centre-split bearing housings on some builds — open the cover and the upper bearing housing halves and the complete rotor lifts out; adjustment is simple and maintenance quick.
Resin sand moulding for casing and cover — holds casting form and passage dimensions accurately with a smooth surface, which is where hydraulic efficiency is either kept or lost.
Water-cooled bearings on some models — allows operation at elevated temperature.
Shaft sleeves — special surface treatment or stainless steel, protecting against rust and extending mechanical seal life.

Sealing

Two arrangements are standard: mechanical seal and packing seal. Special sealing arrangements can be supplied to requirement. Where a mechanical seal is used, the shaft sleeve specification matters as much as the seal itself — a worn or corroded sleeve destroys a good seal quickly.

Hydraulic and Structural Design

The hydraulic passage is developed from a selected hydraulic model and optimised by CFD, which raises hydraulic efficiency and improves cavitation performance. Strength is calculated by finite element analysis so that casing and rotor are dimensioned against actual loading rather than by rule of thumb.

Principal Components

Pump body, pump cover, impeller, shaft, double suction sealing ring, bushings, stuffing box, packing, packing ring, water seal tube, packing gland, bushing nut, fixing screws, bearing body, bearing body gland, single-row radial ball bearings, round nut, coupling components, bearing sleeve, bearing end cover, keys and studs.

Typical Applications

Water supply and transfer at high flow.
Circulating water duty in power generation and metallurgy.
Mine service and process water.
Municipal water works and pumping stations.
Irrigation and drainage schemes.
Industrial cooling water circuits.

Selection

Send the flow and head, the medium and its temperature, the required sealing arrangement and the available power supply and speed. If the pump replaces an existing unit, send the existing baseplate and flange details as well — the split-case arrangement often allows a direct replacement with pipework unchanged. Model-by-model performance data is issued with the quotation.

Send Your Enquiry

Double Suction Pump Distributors & Suppliers

Double Suction Pump for High-Flow Irrigation

Double Suction Pump for Water Supply & HVAC

Parameter	Value
Flow	74–23500 m³/h
Head	7–306 m
Power	15–2500 kW
Materials	Cast iron / SS304 / SS316 / SS316L
Max medium temp	≤80 °C (to ~120 °C)

The table below lists 102 selected models. Download the complete performance data (PDF, 613 models, 37 pages)

Model	Speed (r/min)	Capacity Q (m³/h)	Capacity Q (L/s)	Head H (m)	Shaft power (kW)	Motor power (kW)	Efficiency η (%)	NPSHr (m)	Weight (kg)
150SOM-50	2950	126	35	55	26.6	37	71	5.1	155
		160	44.4	50	27.6		79
		198	55	45	32.4		75
150SOM-50A	2950	110	30.6	42	18.8	30	67	5.1	153
		140	38.9	39	19.8		75
		173	48.1	34	22.6		71
150SOM-50B	2950	102	28.3	36	15.6	22	64	5.1	152
		130	36.1	33	16.2		72
		161	44.7	29	19		67
150SOM-78	2950	100	27.8	85	35.1	55	66	3.7	188
		160	44.4	78	43		79
		200	55.6	70	50.2		76
150SOM-78A	2950	88	24.4	70	26.2	45	64	3.6	185
		150	41.7	65	34		78
		180	50	55	36.4		74
150SOM-78B	2950	88	24.4	62	24.4	37	61	3.5	182
		140	38.9	57	28.2		77
		180	50	48	32.7		72
150SOM-N78	2950	88	24.4	87	35.3	55	59	3.5	185
		145	40.3	78	38.5		80
		180	50	74	47.1		77
150SOM-120	2950	96	26.7	127	51.1	110	65	4.5	208
		160	44.4	120	71.6		73
		202	56.1	108	82.5		72
150SOM-N120	2950	81	22.5	123	46	90	59	4.5	206
		131	36.4	116	56.7		73
		171	47.5	106	69.5		71
150SOM-132	2950	234	65	146	122.4	220	76	7.2	234
		390	108.3	132	171		82
		468	130	108	174.2		79
200SOM-26	2950	168	46.7	31	17.7	30	80	5.9	220
		280	77.8	26	23.3		85
		342	95	19	23		77
200SOM-N26	2950	143	39.7	30	16.2	30	72	5.3	219
		238	66.1	25	19.1		85
		290	80.6	19	19.7		76
200SOM-43	2950	168	46.7	53	34.6	55	70	5.4	220
		280	77.8	43	38.6		85
		342	95	36	41.4		81
200SOM-N43	2950	143	39.7	51	31.5	37	63	5.3	218
		238	66.1	42	32		85
		290	80.6	35	34.6		80
200SOM-64	2950	168	46.7	73	45.8	75	73	5.4	217
		280	77.8	64	58.8		83
		351	97.5	51	63.3		77
200SOM-N64	2950	143	39.7	71	41.9	75	66	5.3	214
		238	66.1	62	48.4		83
		298	82.8	50	53.4		76
200SOM-95	2950	168	46.7	105	75.1	132	64	4.7	240
		280	77.8	95	87.3		83
		326	90.6	85	96.7		78
200SOM-N95	2950	143	39.7	102	68.5	90	58	5.8	238
		238	66.1	92	75.5		79
		285	79.4	83	83.7		77
200SOM-61	2950	320	88.9	75	86	132	76	8.8	280
		534	148.3	61	103.8		85.5
		641	178.1	50	106.4		82
200SOM-61A	2950	298	82.8	65	70.3	110	75	8.7	279
		497	138.1	53	85.4		84
		596	165.7	43	86.2		81
250SOM-75B	1480	282	78.3	72	77.9	132	71	3.3	534
		470	130.6	64	103.7		79
		594	165	55	118.6		75
250SOM-75C	1480	265	73.6	63	65.9	110	69	3.2	532
		441	122.5	56	87.3		77
		550	152.8	48	98.5		73
250SOM-75D	1480	247	68.6	55	55.2	90	67	3	530
		412	114.4	49	73.3		75
		520	144.4	42	83.8		71
250SOM-75E	1480	230	63.9	47	44.6	75	66	2.9	528
		383	106.4	42	59.2		74
		483	134.2	36	67.6		70
250SOM-N75	1480	258	71.7	83	88.4	160	66	3.1	537
		432	120	75	114.6		77
		535	148.6	67	133.7		73
250SOM-N75A	1480	252	70	75	76.8	132	67	3	535
		420	116.7	64	91.5		80
		520	144.4	57	107.6		75
250SOM-N75B	1480	239	66.4	67	67.1	110	65	3	533
		399	110.8	59	82.2		78
		504	140	52	97.8		73
250SOM-N75C	1480	229	63.6	62	61.4	90	63	2.9	531
		382	106.1	54	73		77
		482	133.9	48	87.5		72
250SOM-N75D	1480	214	59.4	54	51.6	75	61	2.8	529
		357	99.2	47	60.1		76
		451	125.3	42	72.7		71
250SOM-N75E	1480	199	55.3	47	43.2	75	59	2.6	527
		332	92.2	41	50.1		74
		419	116.4	36	59.5		69
250SOM-115	1480	301	83.6	122	156.3	280	64	5.1	679
		491	136.4	115	207.8		74
		589	163.6	103	232.7		71
250SOM-115A	1480	291	80.8	106	131.3	220	64	5	677
		485	134.7	100	173.8		76
		582	161.7	91	200.3		72
350SOM-28C	1480	643	178.6	25	65.3	90	67	5.7	702
		1071	297.5	20	71.1		82
		1285	356.9	15	70		75
350SOM-N28	1480	641	178.1	34	89.9	110	66	5.7	707
		1069	296.9	27	89.3		88
		1283	356.4	22	96.1		80
350SOM-46	1480	756	210	54	148.2	220	75	6.3	1110
		1260	350	46	181.4		87
		1512	420	38	195.6		80
350SOM-N46	1480	641	178.1	52	133.5	185	68	5.7	1109
		1069	296.9	44	147.2		87
		1283	356.4	38	168.1		79
350SOM-N46A	1480	609	169.2	47	116.3	160	67	5.6	1107
		1016	282.2	40	128.7		86
		1219	338.6	34	144.7		78
350SOM-N46B	1480	571	158.6	42	100.5	132	65	5.3	1105
		951	264.2	35	107.9		84
		1142	317.2	30	122.8		76
350SOM-N46C	1480	539	149.7	37	86.2	110	63	5.1	1104
		898	249.4	31	92.5		82
		1078	299.4	27	107.1		74
350SOM-77	1480	756	210	86	252.9	355	70	6.3	1208
		1260	350	77	310.8		85
		1512	420	68	345.7		81
350SOM-77A	1480	711	197.5	77	216.1	315	69	6.1	1206
		1184	328.9	69	264.9		84
		1421	394.7	61	295.1		80
400SOM-N160B	1480	929	258.1	123	409.5	630	76	6.7	1944
		1548	430	105	533.3		83
		1935	537.5	89	579		81
400SOM-N160C	1480	875	243.1	98	315.6	450	74	6.6	1941
		1458	405	81	392.2		82
		1823	506.4	68	422		80
400SOM-278	1480	1410	391.7	306	1554.2	2500	75.6	8.8	2780
		2350	652.8	278	2118		84
		2938	816.1	226	2366.8		76.4
400SOM-278A	1480	1354	376.1	281	1387.1	2240	74.7	8.6	2769
		2256	626.7	256	1895		83
		2820	783.3	208	2090.8		76.4
400SOM-278B	1480	1286	357.2	256	1214.8	2000	73.8	8.4	2758
		2143	595.3	233	1658.3		82
		2679	744.2	189	1828.8		75.4
400SOM-278C	1480	1222	339.4	233	1063.6	1800	72.9	8.2	2747
		2036	565.6	212	1451.2		81
		2545	706.9	172	1600.1		74.5
400SOM-278D	1480	1148	318.9	207	898.8	1600	72	8.1	2731
		1914	531.7	189	1231.4		80
		2392	664.4	153	1346.8		74
400SOM-N278	1480	1212	336.7	286	1263.7	2240	74.7	8.6	2775
		2020	561.1	260	1723.2		83
		2525	701.4	211	1899.1		76.4
400SOM-N278D	1480	988	274.4	196	742.8	1400	71	8	2731
		1646	457.2	178	1010		79
		2058	571.7	145	1113.2		73
450SOM-49	1480	1924	534.4	59	406.8	560	76	12.8	1380
		3206	890.6	49	480.7		89
		4008	1113.3	36	467.8		84
450SOM-49A	1480	1802	500.6	52	340.2	450	75	12.7	1378
		3004	834.4	43	399.7		88
		3755	1043.1	32	394.3		83
450SOM-49B	1480	1681	466.9	46	284.6	355	74	12.6	1376
		2802	778.3	37	324.5		87
		3503	973.1	26	302.5		82
500SOM-100C	990	1067	296.4	85	368.6	560	67	4.6	2602
		1778	493.9	77	482.2		77
		2133	592.5	70	542.2		75
500SOM-100D	990	994	276.1	75	312.3	450	65	4.4	2600
		1656	460	67	402.9		75
		1988	552.2	60	439		74
500SOM-N100	990	1028	285.6	103	436.9	630	66	4.5	2606
		1714	476.1	95	534.3		83
		2057	571.4	88	632		78
500SOM-47	1480	1902	528.3	59	413	560	74	12.8	1680
		3170	880.6	48	470.9		88
		3963	1100.8	36	468.1		83
500SOM-N47	1480	1614	448.3	57	334.1	450	75	12.2	1678
		2690	747.2	46	387.3		87
		3363	934.2	36	392.5		84
500SOM-N47A	1480	1536	426.7	50	286.5	355	73	12	1676
		2560	711.1	40	328.1		85
		3200	888.9	30	318.8		82
500SOM-N47B	1480	1494	415	43	249.9	280	70	11.9	1674
		2490	691.7	32	264.6		82
		3113	864.7	24	264.2		77
500SOM-N47C	1480	1386	385	37	205.4	250	68	11.8	1672
		2310	641.7	28	223		79
		2888	802.2	20	209.7		75
600SOM-N158B	990	1964	545.6	138	1011.1	1800	73	8.6	4643
		3274	909.4	125	1375.9		81
		4093	1136.9	102	1536.4		74
600SOM-N158C	990	1866	518.3	126	889.3	1600	72	8.4	4640
		3110	863.9	114	1206.9		80
		3888	1080	93	1348.9		73
600SOM-N158D	990	1754	487.2	112	753.5	1400	71	8.3	4636
		2924	812.2	102	1028.1		79
		3655	1015.3	83	1131.7		73
700SOM-24	990	2824	784.4	33	317.2	400	80	8	3500
		4707	1307.5	24	349.6		88
		5648	1568.9	20	370.6		83
700SOM-N24	990	2600	722.2	32	286.8	355	79	7.8	3500
		4334	1203.9	23	308.5		88
		5201	1444.7	19	324.2		83
700SOM-46	990	3000	833.3	56	557.9	800	82	7.2	3670
		5000	1388.9	46	680.8		92
		6000	1666.7	36	692		85
700SOM-46A	990	2808	780	48	453.2	630	81	7.1	3665
		4680	1300	40	560.2		91
		5616	1560	32	582.6		84
700SOM-46B	990	2661	739.2	44	403.6	560	79	7	3660
		4435	1231.9	36	483.1		90
		5322	1478.3	28	488.9		83
700SOM-46C	990	2564	712.2	40	358.1	500	78	6.9	3655
		4274	1187.2	33	436.5		88
		5129	1424.7	27	454.4		83
800SOM-53B	740	3600	1000	56	703.9	1000	78	6.3	6090
		6000	1666.7	45	835.6		88
		7200	2000	39	968		79
800SOM-53C	740	3456	960	52	627.5	900	78	6.2	6085
		5760	1600	42	757.3		87
		6912	1920	37	892.9		78
800SOM-N53	740	3390	941.7	64	720.5	1000	82	5.6	6100
		5650	1569.4	53	886.4		91
		6780	1883.3	45	989.1		84
800SOM-70	740	4500	1250	83	1271.4	1800	80	6.8	7800
		7500	2083.3	70	1571.1		91
		9000	2500	55	1624.1		83
800SOM-70A	740	4179	1160.8	71	1022.8	1600	79	6.7	7795
		6965	1934.7	60	1264.5		90
		8357	2321.4	50	1387.7		82
800SOM-N70	740	3780	1050	79	1029.4	1600	79	6.3	7795
		6300	1750	67	1277.2		90
		7560	2100	54	1339.5		83
800SOM-N70A	740	3480	966.7	68	836.9	1250	77	6.2	7790
		5800	1611.1	58	1029.4		89
		6960	1933.3	50	1155.7		82
800SOM-N70C	740	3030	841.7	49	553.9	800	73	6	7780
		5050	1402.8	43	695.7		58
		6060	1683.3	36	752		79
900SOM-26	740	5616	1560	36	688.2	900	80	9	7780
		9360	2600	26	744.7		89
		11232	3120	22	810.8		83
900SOM-N40A	740	4896	1360	47	793.2	1120	79	8.2	8530
		8160	2266.7	36	898.9		89
		9792	2720	31	996		83
900SOM-N40B	740	4700	1305.6	43	696.7	1000	79	8.1	8510
		7834	2176.1	33	800		88
		9400	2611.1	27	842.9		82
900SOM-N40C	740	4512	1253.3	40	630.1	900	78	8	8490
		7520	2088.9	30	714.4		86
		9024	2506.7	24	728.2		81
900SOM-N40D	740	4332	1203.3	36	551.6	710	77	7.9	8470
		7219	2005.3	26	601.4		85
		8663	2406.4	20	597.3		79
1000SOM-24	585	6948	1930	34	804.3	1000	80	7.9	10840
		11580	3216.7	24	841		90
		13896	3860	20	901		84
1000SOM-24A	585	6670	1852.8	33	749.3	900	80	7.7	10820
		11117	3088.1	23	782.4		89
		13340	3705.6	18	787.9		83
1000SOM-N24	585	5508	1530	29	543.8	560	80	7.2	10800
		9180	2550	19	533.7		89
		11016	3060	15	542.2		83
1000SOM-39	585	8111	2253.1	43	1187.3	1800	80	6.6	12560
		13518	3755	39	1577.7		91
		15901	4416.9	34	1752.8		84
1200SOM-62A	590	8740	2427.8	65	1886.7	2500	82	7.5	12790
		14567	4046.4	51	2248		90
		17480	4855.6	42	2352.2		85
1200SOM-62B	590	8304	2306.7	59	1647.2	2000	81	7.3	12760
		13840	3844.4	44	1863.4		89
		16608	4613.3	36	1938.4		84
1200SOM-62C	590	7970	2213.9	55	1492.2	1800	80	7.1	12730
		13283	3689.7	40	1644.3		88
		15940	4427.8	32	1673.6		83
1200SOM-N62	590	7739	2149.7	77	1979.1	2800	82	6.6	15790
		12898	3582.8	62	2419.7		90
		15477	4299.2	51	2528.9		85
1400SOM-19	425	13356	3710	28	1273	1600	80	7.8	24840
		22260	6183.3	19	1294.2		89
		26712	7420	12	1051.7		83
1400SOM-19A	425	12822	3561.7	25	1105		79	7.7	24820
		21370	5936.1	16	1058.1		88
		25644	7123.3	10	851.7		82
1400SOM-N19	425	11950	3319.4	30	1220.4	1400	80	6.3	24840
		19916	5532.2	21	1265.5		90
		23899	6638.6	13	1019.4		83
1400SOM-N19A	425	11472	3186.7	28	1107.3	1250	79	6.1	24820
		19120	5311.1	18	1065.1		88
		22944	6373.3	12	914.4		82
1400SOM-N19B	425	11013	3059.2	26	999.7	1120	78	5.9	24800
		18355	5098.6	16	919.3		87
		22026	6118.3	9	666.5		81
1600SOM-20	372	15011	4169.7	27	1379.7	1600	80	7.5	35160
		25018	6949.4	20	1481.1		92
		30022	8339.4	15	1460		84
1600SOM-20A	372	14260	3961.1	25	1213.6	1400	80	7.3	35140
		23767	6601.9	18	1294.5		90
		28521	7922.5	13	1205		83
1600SOM-20B	372	13690	3802.8	22	1038.2	1120	79	7.1	35120
		22816	6377.8	15	1059.1		88
		27380	7605.6	11	1000.3		82
1600SOM-N20	372	12759	3544.2	26	1129.3	1250	80	7.3	35160
		21265	5906.9	18	1145.5		91
		25518	7088.3	13	1088.5		83
1600SOM-N20A	372	12249	3402.5	24	1013.4	1200	79	7.1	35140
		20414	5670.6	16	988.3		90
		24497	6804.7	11	894.9		82
1600SOM-N20B	372	11759	3266.4	21	851.3	900	79	6.9	35120
		19598	5443.9	13	788.4		88
		23517	6532.5	8	632.5		81

Why is a split casing worth paying for?

The rotating assembly is removed by lifting the top half of the casing, with suction and discharge pipework left bolted in place. On continuously running duty that shortens every inspection and overhaul.

What does double suction achieve?

Liquid enters from both sides so axial hydraulic loads largely cancel. The bearings carry radial load only, which allows high flow at moderate head without the axial thrust that limits a single-suction pump.

Can it handle anything other than clean water?

The standard build is for clean water and media of similar physical properties. Other liquids can be handled by changing the wet-end material and the sealing arrangement — specify the medium at enquiry.

What flow range does the series cover?

74 to 23,500 m³/h across the range. Model-by-model data is issued with the quotation.

Does the shaft contact the medium?

No. The fully enclosed shaft design keeps the shaft out of the pumped liquid, so it does not corrode and is normally reusable at overhaul.

Manufacturer-direct supply · Technical pump-selection support · Export documentation on request.