Description

Marine horizontal vortex pump

I. Overview: The W-type vortex pump is suitable for pumping clean water and mildly corrosive liquid media in marine applications.

Viewed from the drive end, the pump rotates clockwise.

II. Pump Model and Performance Parameters:

Serial Number	model	flow （L/s）	Water pump head （m）	rotational speed (r/min)	motor power (Kw)	Required net positive suction head (NPSH)r (m)
1	20W-20	0.1 0.2 0.25	28 20 15	2900	0.75	3 3.5 4
2	20W-65	0.1 0.2 0.25	80 65 50		2.2	3.5 4 4.5
3	25W-25	0.22 0.4 0.5	40 25 18		0.75	3.5 4 4.5
4	25W-70	0.22 0.4 0.5	110 70 52		3	4 4.5 5
5	32W-30	0.48 0.8 1	52 30 20		1.5	3.5 4 4.5
6	32W-75	0.48 0.8 1	115 75 53	2900	4	4.5 5 5.5
7	40W-40	1 1.5 1.8	60 40 26		4	4 5 6
8	40W-90	1 1.5 1.8	132 90 63		7.5	5.5 6.5 7.5
9	50W-45	1.7 2.5 3	66 45 28		5.5	5 6 7
10	65W-50	2.8 4 4.7	84 50 30		11	5.5 6.5 7.5

How to select a marine horizontal vortex pump?

I. Defining Operating Parameters (Crucial First Step)

Media Confirmation

Media Name (e.g., seawater, fresh water, oil, sewage, etc.)

Media Temperature (e.g., seawater 25-35℃)

Media Corrosivity (Contains salt, acidity, or alkalinity)

Contains solid particles, particle size and content (affects whether to select a wear-resistant type)

Viscosity (e.g., 1 cP for general water; high-viscosity media require special design)

Flow Rate and Head

Flow Rate Q, unit m³/h, e.g., 50 m³/h
Total Head H, unit m, e.g., 20 m Consider pipeline length, pipe diameter, number of bends, and loss coefficient during calculation to ensure accuracy.

Working Environment

Ship space size, limiting pump size and weight

Are there requirements for tilting, vibration, or impact?

Special specifications for explosion-proof and corrosion-proof (according to classification societies) II. Selecting Pump Structure and Materials

Pump Body and Impeller Materials

Seawater Media ① Recommended ① Aluminum bronze ② Nickel-chromium bronze ③ 316 stainless steel (corrosion resistant)

Fresh water and non-corrosive media can use cast iron or carbon steel.

Hydraulic oil and other media require oil-resistant rubber/special alloy seals.

Sealing Type:

Mechanical seals are preferred; for seawater, silicon carbide/silicon carbide or silicon carbide/silicon carbide mechanical seals are generally selected.

Packaging seals are low-cost but not safe enough for marine environments, with a high risk of leakage.

Bearings:

Rolling bearings are used, with dustproof seals and grease lubrication.

Bearing design must prevent seawater intrusion, and the lifespan must be at least compatible with the ship’s lifespan (more than 1 year of continuous operation).

Pump Structure:

Horizontal design is suitable for limited space on ships and facilitates on-site disassembly and maintenance.

Confirm pump shaft position, inlet direction, and flange interface dimensions.

III. Performance Matching and Efficiency Considerations

Performance Curve Selection:

The design point flow rate and head must fall within the pump’s optimal efficiency range to avoid pump “overload.”

If the design point flow rate is off… If the pump is outside its efficiency range, consider changing the model or adjusting parameters.
**Marginal Design:** Allow 10-20% margin in head and power to ensure stable operation and reduce failure rate.
**Cavitation Prevention:** Calculate the net positive suction head according to NPSH requirements to ensure the pump inlet pressure is higher than NPSH, preventing cavitation damage.
**IV. Drive and Transmission:**
**Motor Selection:** Select the appropriate motor based on power rating. Marine motors require IP56 or higher protection rating.
**Explosion-proof Requirements:** Select Exd, Exe, or other explosion-proof motors based on the marine environment.
**Couplings:** Flexible couplings buffer vibration and ensure stable transmission. High-precision couplings are required; maintain alignment during installation.
**V. Installation and Maintenance Convenience:**
**Size Matching:** Flange diameter and shape should conform to shipboard piping standards (e.g., GB/T, ISO, etc.).
**Reasonable Piping Interface Design:** Prevents unnecessary pressure loss.
**Easy Maintenance:** Shaft seals and bearings are easily disassembled and readily available. Spare parts package provided. Easy monitoring of operating status via inspection port. Noise reduction measures: Bearing and impeller design minimizes noise. Sound absorption and vibration isolation are considered during installation to reduce cabin noise. VI. Classification Society and Safety Certifications: Classification society certification requirements: CCS, ABS, DNV, LR, etc., ensuring product compliance with regulations. Production and inspection processes comply with ISO9001 series quality management system. Safety protection: Necessary measures such as corrosion prevention, explosion prevention, fire prevention, and electrical safety insulation. VII. Supplier Selection: Manufacturer qualifications: Select experienced marine pump manufacturers with comprehensive service networks and timely technical support. After-sales service: Clear warranty period. Complete spare parts supply for rapid delivery. Technical training and installation/commissioning support. VIII. Actual Selection and Operation Example: Assumptions:

Horizontal vortex pump for ship cooling system. Seawater medium, temperature 30℃. Flow rate 60 m³/h. Head 22 m. Low sand content. Operation steps:

Confirm pump material: Select aluminum bronze pump body and impeller.

Seal: Select mechanical seal, material silicon carbide. Determine the pump model: Consult the corresponding performance curve to find the optimal efficiency point at a flow rate of 60 m³/h and a head of 22 m.

Bearings: Use well-sealed, grease-lubricated rolling bearings.

Select a drive motor with a power rating 10% higher than the calculated shaft power, and choose an IP56 protection rating.

Flange diameter should correspond to DN80 or the customer’s piping standard.

The supplier should provide classification society certificates confirming compliance with CCS certification.

Considering installation space, purchase a structure with a vibration-damping base.