Light-duty Stainless Steel Vertical Multistage Centrifugal Pump

Product Application

Pressurization Water Supply: Water plant filtration & transmission, main pipe network pressurization, high-rise building water supply, fire water supply;
Water Treatment System: Ultrafiltration system, reverse osmosis system, distillation system, separator and swimming pool water treatment system;
Industrial Pressurization: High-pressure flushing system, cleaning system, process water system;
Industrial Liquid Transport: Cooling & air conditioning system, boiler feed water & condensate system, machine tool supporting;
Irrigation: Farmland irrigation, sprinkler irrigation, drip irrigation, etc.

Operating Conditions

Thin, clean liquid free of solid particles or fibers

Applicable for transporting mildly corrosive media

Medium Temperature: Normal temperature type 0℃～68℃, hot water type 0℃～120℃

Ambient Temperature: -15℃～+40℃

Max Ambient Pressure: 1.0 MPa

When the density or viscosity of transported medium is higher than water, a higher-power motor shall be considered.

BL/BLT series light-duty stainless steel vertical multi-stage centrifugal pump is a versatile product. It adopts optimized hydraulic models and advanced manufacturing processes. The wetted parts of the pump are stamped and welded from high-quality 304 stainless steel. The shaft seal adopts mechanical seal with hard alloy and fluororubber.
It can transport various media ranging from tap water to industrial liquids and is applicable for different temperature, flow rate and pressure ranges. The complete pump features compact structure, low noise, small footprint and remarkable energy-saving performance.

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	1 0.28 L/S	1.2 0.33 L/S	1.6 0.44 L/S	2.0 0.56 L/S	2.4 0.67 L/S	2.8 0.78 L/S	3.2 0.89 L/S	3.5 0.97 L/S
BL(T)2-2	0.37	220/380	DN32	H(m)	18	17	16	15	13	12	10	8
BL(T)2-3	0.37	220/380	DN32	H(m)	27	26	24	22	20	18	15	12
BL(T)2-4	0.55	220/380	DN32	H(m)	36	35	33	30	26	24	20	16
BL(T)2-5	0.55	220/380	DN32	H(m)	45	43	40	37	33	30	24	20
BL(T)2-6	0.75	220/380	DN32	H(m)	53	52	50	45	40	36	30	24
BL(T)2-7	0.75	220/380	DN32	H(m)	63	61	57	52	47	41	28	28
BL(T)2-9	1.1	220/380	DN32	H(m)	80	78	73	67	61	54	51	37
BL(T)2-11	1.1	220/380	DN32	H(m)	98	95	89	82	73	64	54	44
BL(T)2-13	1.5	220/380	DN32	H(m)	116	114	106	98	89	78	67	52
BL(T)2-15	1.5	220/380	DN32	H(m)	134	130	123	112	100	90	76	60
BL(T)2-18	2.2	220/380	DN32	H(m)	161	157	148	136	121	108	91	76
BL(T)2-22	2.2	220/380	DN32	H(m)	197	192	180	165	148	130	110	90
BL(T)2-26	3	220/380	DN32	H(m)	232	228	214	198	179	158	130	110

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	1.5 0.42 L/S	2.0 0.56 L/S	3.0 0.83 L/S	4.0 1.11 L/S	5.0 1.39 L/S	6.0 1.67 L/S	7.0 1.94 L/S
BL(T)4-2	0.37	220/380	DN32	H(m)	19	18	17	15	13	10	8
BL(T)4-3	0.55	220/380	DN32	H(m)	28	27	26	24	20	18	13
BL(T)4-4	0.75	220/380	DN32	H(m)	38	36	34	32	27	24	19
BL(T)4-5	1.1	220/380	DN32	H(m)	47	45	43	40	34	31	23
BL(T)4-6	1.1	220/380	DN32	H(m)	56	54	52	48	40	37	28
BL(T)4-7	1.5	220/380	DN32	H(m)	66	63	59	56	48	43	33
BL(T)4-8	1.5	220/380	DN32	H(m)	74	72	67	64	55	50	38
BL(T)4-10	2.2	220/380	DN32	H(m)	90	87	81	75	65	62	48
BL(T)4-12	2.2	220/380	DN32	H(m)	114	108	104	95	82	75	58
BL(T)4-14	3	220/380	DN32	H(m)	136	126	122	112	101	89	68
BL(T)4-16	3	220/380	DN32	H(m)	152	144	140	129	115	101	78
BL(T)4-19	4	380	DN32	H(m)	183	171	168	153	137	122	93
BL(T)4-22	4	380	DN32	H(m)	211	200	192	178	160	138	108

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	5 1.39 L/S	6 1.67 L/S	7 1.94 L/S	8 2.22 L/S	9 2.5 L/S	10 2.78 L/S	11 3.06 L/S
BL(T)8-2	0.75	220/380	DN50	H(m)	20	19.5	19	18	17	16	14
BL(T)8-3	1.1	220/380	DN50	H(m)	30	29.5	28.5	27	25	24	13
BL(T)8-4	1.5	220/380	DN50	H(m)	41	39.5	38	36	34	32	19
BL(T)8-5	2.2	220/380	DN50	H(m)	52	50	48	45	42	40	26
BL(T)8-6	2.2	220/380	DN50	H(m)	62	60	57	54	50	46	32
BL(T)8-8	3	220/380	DN50	H(m)	83	80	77	73	69	65	39
BL(T)8-10	4	380	DN50	H(m)	104	100	97	92	87	81	50
BL(T)8-11	4	380	DN50	H(m)	114	110	106	101	95	86	55
BL(T)8-12	5.5	380	DN50	H(m)	124	120	116	104	104	87	78
BL(T)8-14	5.5	380	DN50	H(m)	145	141	136	130	122	113	102
BL(T)8-16	7.5	380	DN50	H(m)	166	161	156	148	139	118	106
BL(T)8-18	7.5	380	DN50	H(m)	187	182	175	167	157	134	120
BL(T)8-20	7.5	380	DN50	H(m)	208	202	195	186	175	150	135

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	7 1.94 L/S	8 2.22 L/S	9 2.5 L/S	10 2.78 L/S	11 3.06 L/S	12 3.33 L/S	13 3.61 L/S	14 3.89 L/S	15 4.17 L/S	16 4.44 L/S
BL(T)12-2	1.5	220/380	DN50	H(m)	23.5	23	22.5	22	21	20	18.5	17	15	14
BL(T)12-3	2.2	220/380	DN50	H(m)	35.5	35	34	33	31.5	30	27	26	23	21
BL(T)12-4	3	220/380	DN50	H(m)	47	46	44	44	42	40	34	30	31	28
BL(T)12-5	3	380	DN50	H(m)	59.5	58	56.5	55	52.5	50	43	38	39	35
BL(T)12-6	4	380	DN50	H(m)	71.5	70	66	66	63	60	52	45	45	42
BL(T)12-7	5.5	380	DN50	H(m)	83.5	82	79.5	77	73.5	70	61	53	55	49
BL(T)12-8	5.5	380	DN50	H(m)	95.5	94	88	88	84	80	70	61	65	56
BL(T)12-9	5.5	380	DN50	H(m)	108	106	103	100	95.5	90	79	69	74	64
BL(T)12-10	7.5	380	DN50	H(m)	120	118	114.5	111	106.5	100	88	77	80	72
BL(T)12-12	7.5	380	DN50	H(m)	143.5	141	137	133	127	120	106	92	96	86
BL(T)12-14	11	380	DN50	H(m)	168	165	160	155	148	140	132.5	124	112	100
BL(T)12-16	11	380	DN50	H(m)	192.5	189	183.5	178	170	162	142	142	128	115
BL(T)12-18	11	380	DN50	H(m)	217	213	207.5	202	192.5	183	151.5	160	145	130

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	8 2.22 L/S	10 2.77 L/S	12 3.33 L/S	14 3.89 L/S	16 4.44 L/S	18 5.00 L/S	20 5.56 L/S	22 6.11 L/S
BL(T)16-2	2.2	220/380	DN50	H(m)	27	26	25	24	23	21	19	16
BL(T)16-3	3	220/380	DN50	H(m)	41	40	38	37	34	32	29	25
BL(T)16-4	4	380	DN50	H(m)	54	53	50	48	45	42	37	34
BL(T)16-5	5.5	380	DN50	H(m)	68	67	65	62	58	54	49	43
BL(T)16-6	5.5	380	DN50	H(m)	82	80	78	74	70	65	58	52
BL(T)16-7	7.5	380	DN50	H(m)	96	95	90	86	82	76	68	61
BL(T)16-8	7.5	380	DN50	H(m)	110	108	104	99	95	87	78	70
BL(T)16-10	11	380	DN50	H(m)	138	136	131	125	118	109	97	85
BL(T)16-12	11	380	DN50	H(m)	166	162	157	151	141	132	116	105
BL(T)16-14	15	380	DN50	H(m)	194	190	184	175	166	152	136	122
BL(T)16-16	15	380	DN50	H(m)	222	217	210	200	189	174	156	140

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	10 2.78 L/S	12 3.33 L/S	14 3.89 L/S	16 4.44 L/S	18 5.00 L/S	20 5.56 L/S	22 6.11 L/S	24 6.67 L/S	26 7.22 L/S	28 7.78 L/S
BL(T)20-2	2.2	220/380	DN50	H(m)	27	26.5	25	24	23	22	21	20	18	15
BL(T)20-3	4	380	DN50	H(m)	40	39.5	39	37	35	34	31	29	27	24
BL(T)20-4	5.5	380	DN50	H(m)	54	53	52	50	49	47	44	41	38	33
BL(T)20-5	5.5	380	DN50	H(m)	67	66	64	62	60	58	53	50	46	40
BL(T)20-6	7.5	380	DN50	H(m)	81	79	77	75	72	70	65	61	55	49
BL(T)20-7	7.5	380	DN50	H(m)	95	93	91	89	86	82	77	71	66	58
BL(T)20-8	11	380	DN50	H(m)	109	105	105	102	99	94	89	82	76	67
BL(T)20-10	11	380	DN50	H(m)	136	134	128	124	118	113	111	103	93	81
BL(T)20-12	15	380	DN50	H(m)	164	162	158	150	142	138	133	124	114	102
BL(T)20-14	15	380	DN50	H(m)	192	189	185	174	174	166	156	145	133	119
BL(T)20-17	18.5	380	DN50	H(m)	234	230	225	212	202	192	190	177	162	145

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	30 8.33 L/S	40 11.11 L/S	50 13.89 L/S	60 16.67 L/S	64 17.78 L/S	70 19.44 L/S	80 22.22 L/S
BL(T)64-2-2	7.5	380	DN100	H(m)	39	36	33	29	26	23	17
BL(T)64-2-1	11	380	DN100	H(m)	46	44	40	36	33	30	24
BL(T)64-2	11	380	DN100	H(m)	53	51	47	43	40	37	31
BL(T)64-3-2	15	380	DN100	H(m)	66	62	56	50	46	41	32
BL(T)64-3-1	15	380	DN100	H(m)	73	69	63	57	53	48	39
BL(T)64-3	18.5	380	DN100	H(m)	80	76	71	65	59	56	46
BL(T)64-4-2	18.5	380	DN100	H(m)	92	87	80	71	67	61	47
BL(T)64-4-1	22	380	DN100	H(m)	100	94	78	73	73	65	54
BL(T)64-4	22	380	DN100	H(m)	107	101	94	85	80	74	61
BL(T)64-5-2	30	380	DN100	H(m)	121	114	105	95	88	80	64
BL(T)64-5-1	30	380	DN100	H(m)	128	121	112	102	95	87	71
BL(T)64-5	30	380	DN100	H(m)	136	129	119	109	102	94	78
BL(T)64-6-2	30	380	DN100	H(m)	150	142	131	120	110	101	81
BL(T)64-6-1	37	380	DN100	H(m)	157	149	138	125	117	108	88
BL(T)64-6	37	380	DN100	H(m)	164	156	145	132	124	115	95
BL(T)64-7-2	37	380	DN100	H(m)	179	169	156	141	132	121	99
BL(T)64-7-1	37	380	DN100	H(m)	186	176	163	148	139	128	106
BL(T)64-7	45	380	DN100	H(m)	193	183	170	155	146	135	112
BL(T)64-8-2	45	380	DN100	H(m)	207	196	182	164	154	142	116
BL(T)64-8-1	45	380	DN100	H(m)	214	203	189	171	161	149	123
BL(T)64-8	45	380	DN100	H(m)	221	210	196	178	168	156	130

Model	Power(kW)	Voltage(V)	Inlet / Outlet Diameter	Q(m³/h)	50 13.89 L/S	60 16.67 L/S	70 19.44 L/S	80 22.22 L/S	90 25 L/S	100 27.78 L/S	110 30.56 L/S
BL(T)90-2-2	11	380	DN100	H(m)	41	39	36	32	28	22	15
BL(T)90-2	15	380	DN100	H(m)	53	50	47	44	40	36	26
BL(T)90-3-2	18.5	380	DN100	H(m)	68	65	60	55	49	45	34
BL(T)90-3	22	380	DN100	H(m)	81	77	72	67	55	55	48
BL(T)90-4-2	30	380	DN100	H(m)	98	93	87	80	72	62	50
BL(T)90-4	30	380	DN100	H(m)	110	105	100	92	84	76	66
BL(T)90-5-2	37	380	DN100	H(m)	126	120	113	104	93	91	68
BL(T)90-5	37	380	DN100	H(m)	139	131	124	115	106	94	83
BL(T)90-6-2	45	380	DN100	H(m)	155	148	139	129	117	102	86
BL(T)90-6	45	380	DN100	H(m)	168	160	150	141	130	117	103

1. Product Features

Structure It adopts vertical coaxial multistage construction, with the motor mounted on the top and multistage impellers connected in series vertically downward in the pump body. It features a compact footprint and requires minimal installation space. The pump shaft is directly coupled with the motor for simple installation. The wetted components (impellers, diffusers, pump chambers, inlet & outlet flanges) are made of stainless steel (normally 304, with 316L optional for certain working conditions). As a light-duty design, it comes with thinner casing walls, which differentiates it from heavy-duty industrial multistage pumps.
Hydraulic Performance Pressurization is realized stage by stage through multistage impellers. It delivers low flow rate with high head. Its flow range is generally several cubic meters up to dozens of cubic meters per hour, while the head can reach tens to more than 300 meters. Stable continuous outlet pressure with low pressure pulsation during operation.

Precisely stamped hydraulic components with smooth surfaces for good hydraulic efficiency;
No rust contamination to conveyed fluid;
Suitable for clean water or thin low-corrosive liquids. Not applicable for media with high sand content or large solid particles due to weak wear resistance of the light-duty structure.

Material Advantages Stainless steel wetted parts provide corrosion resistance and good hygienic performance. Lighter in weight compared with cast iron multistage pumps, easier for transportation and maintenance. However, its casing has lower pressure safety margin than heavy cast steel pumps with a lower maximum rated pressure, and long-time overpressure operation is prohibited.
Operating Characteristics

Low noise and slight vibration;
Compatible with variable-frequency motors to achieve constant-pressure water supply and automatic pressure regulation;
Mechanical seal serves as the primary shaft seal with extremely low leakage under normal working conditions;
Applicable medium temperature range is usually 0~80℃ (hot water version available up to 120℃).

Limitations (Key for Light-duty Type) The light-duty version cannot handle heavy loads, frequent pressure shocks or media with high solid content. Dry running and abrupt pressure changes will easily damage mechanical seals and stamped impellers.

2. Application Scenarios

Building Water Supply (Most Common) Secondary pressurized water supply for high-rise residential buildings, office buildings and hotels; constant-pressure water supply sets in pump rooms equipped with VFD control cabinets to maintain stable pipeline water pressure.
Water Treatment Industry Pressurization for reverse osmosis (RO) and ultrafiltration systems in pure water production; clean water delivery for water purification plants and bottled water production lines; transportation of softened water and deionized water.
HVAC Systems Make-up water pumps for central air-conditioning cooling water, low-pressure boiler feed water, hot water pressurization and floor heating system pressurization.
Light Industry Clean water transportation in food & beverage industry (304/316L hygienic type); purified water delivery for pharmaceutical industry; thin low-corrosive solutions in chemical industry (clean water-like, dilute weakly acidic/alkaline liquids, material verification required).
Other Applications Fire sprinkler jockey pump (some models meet jockey pump parameters, cannot be used as main fire pump); high-pressure garden irrigation and pressurization for small cleaning equipment.

Not suitable for sewage, sediment-laden groundwater, high-concentration acid & alkali, high-viscosity media or heavy-duty high-temperature & high-pressure process conditions.

3. Routine Maintenance

3.1 On-site Inspection (During Operation)

Monitor outlet pressure and flow for stability and abnormal fluctuations;
Listen to pump and motor for abnormal friction or impact noise;
Check mechanical seal: only tiny dripping is permitted under normal status. Replace the seal immediately if leakage increases continuously;
Motor shell temperature generally shall not exceed 80℃; check operating current, which cannot exceed the rated value on nameplate;
Inspect pipelines and flanges for leakage, and check anchor bolts for looseness.

3.2 Periodic Servicing

Weekly: Check pressure gauges, valves and vibration dampers; clean dust and debris off pump exterior.
Monthly: Tighten anchor bolts; inspect motor bearing noise; check heat dissipation of control cabinet for VFD units.
Every 6 Months:
- Inspect wear condition of mechanical seal;
- Check impellers and diffusers for scale or blockage by impurities;
- Measure motor insulation resistance;
- Clean inlet strainer.
Annual Overhaul: Disassemble and inspect corrosion and wear of impellers and diffusers; replace aged mechanical seals and O-rings; check pump shaft wear and realign concentricity; remove scale inside pump chamber.

For long-term shutdown: drain all liquid inside pump chamber to prevent freeze cracking and internal corrosion; keep pump dry.

3.3 List of Wearing Parts

Mechanical seal, rubber O-rings, bearings, check valve assembly, inlet filter screen.

4. Operation Precautions

Dry Running Strictly Forbidden The pump must be primed and all air vented before startup. Even short-time dry running will burn out mechanical seals, which is the most frequent failure of light-duty stainless steel multistage pumps. An inlet strainer must be installed to prevent solid particles from entering and scratching impellers and seals.
Medium Requirements Conveyed liquid must be clean with negligible solid particles. The medium shall not cause severe corrosion to stainless steel. Grade 304 is only suitable for clean water and neutral mild media. 316L stainless steel shall be selected for high chloride water (seawater, high-chloride groundwater).
Installation & Piping

Level the pump during installation. Inlet and outlet pipes shall be independently supported. Do not let pipeline weight bear on pump flanges, otherwise the thin stainless steel pump casing may crack.
Inlet piping must be airtight; air ingress leads to pump cavitation, unstable pressure and component damage.
Flexible connectors are recommended at inlet and outlet for vibration isolation. A check valve shall be fitted at pump outlet to protect stamped impellers from water hammer upon shutdown.

Startup & Shutdown

Open inlet valve and close outlet valve before startup; slowly open outlet valve after power-on.
Frequent start-stop under full load is prohibited.
Stop pump immediately once cavitation occurs (loud noise and violent pressure fluctuation). Sustained cavitation will rapidly erode stainless steel impellers.

Temperature & Pressure Do not exceed the medium temperature and maximum working pressure marked on nameplate. Long-term overpressure operation is prohibited. The stamped light-duty stainless steel casing has low pressure margin and is prone to deformation and leakage under overpressure.
Electrical Safety Reliable earthing of motor; waterproof measures for humid pump rooms. For VFD operation, configure parameters per manufacturer requirements to avoid motor overheating caused by prolonged low-frequency running.
Anti-freezing Protection When ambient temperature is below 0℃, drain all liquid inside pump after shutdown to prevent freeze burst.