burks BLW Series Cooling Tower Pump

Product Overview

The burks BLW cooling tower pump is a non-self-priming, horizontal single-stage centrifugal pump with axial inlet and radial outlet. The pump is directly coupled to the motor, giving a compact unit that is easy to maintain. The range covers 9 models with DN65–DN150 connections, rated flows of 45–260 m³/h, rated heads of 5–6 m and motor powers of 1.1–7.5 kW — a high-flow, low-head pump designed for cooling tower water circulation.

Features

● Direct-coupled pump and motor: compact size, easy maintenance.

● High-efficiency hydraulic model for the pump body and impeller: high efficiency, low noise.

● Castings made by lost-foam casting: uniform wall thickness, smooth surface.

● Impeller made by stainless steel precision casting: accurate profile, smooth and attractive surface.

● Totally enclosed, fan-cooled motor with custom shaft extension, suitable for continuous duty.

Model Code

Example BLW150-6AS: BL = cooling tower pump; W = horizontal (L = vertical); 150 = inlet/outlet diameter DN150; 6 = rated head 6 m; A = trimmed impeller (B = second trim); S = 304 stainless steel impeller (P = 316). The number after the slash is the motor power, e.g. BLW65-5/1.1 means a rated head of 5 m with a 1.1 kW motor.

Technical Data

Operating Conditions

● Thin, clean, non-flammable and non-explosive liquids without particles or fibres.

● Ambient temperature: not above +40 °C.

● Altitude: not above 1000 m.

● Maximum working pressure: 6 bar.

Typical Applications

● Water circulation for closed cooling towers and condensers.

● Cooling of various machine units and equipment.

● Other high-flow, low-head circulation water supply duties.

Construction and Materials

Sectional drawing parts: 1 pump body; 2 impeller; 3 mechanical seal; 4 pump head; 5 O-ring; 6 motor; 7 base.

Performance Range

Models and Rated Performance

BLW65-5/1.1: rated flow 45 m³/h, rated head 5 m, motor 1.1 kW, 2900 r/min, weight 28 kg.

BLW80-5/1.5: rated flow 55 m³/h, rated head 5 m, motor 1.5 kW, 2900 r/min, weight 34 kg.

BLW100-5A/2.2: rated flow 100 m³/h, rated head 5 m, motor 2.2 kW, 1450 r/min, weight 56 kg.

BLW100-5/2.2: rated flow 120 m³/h, rated head 5 m, motor 2.2 kW, 1450 r/min, weight 56 kg.

BLW125-5A/3: rated flow 150 m³/h, rated head 5 m, motor 3 kW, 1450 r/min, weight 70 kg.

BLW125-5/4: rated flow 180 m³/h, rated head 5 m, motor 4 kW, 1450 r/min, weight 77 kg.

BLW150-6B/5.5: rated flow 220 m³/h, rated head 6 m, motor 5.5 kW, 1450 r/min, weight 114 kg (shares dimensions with 6A).

BLW150-6A/5.5: rated flow 240 m³/h, rated head 6 m, motor 5.5 kW, 1450 r/min, weight 114 kg.

BLW150-6/7.5: rated flow 260 m³/h, rated head 6 m, motor 7.5 kW, 1450 r/min, weight 119 kg.

Performance Curves

All 50 Hz curves are based on 3×380 V measurements at a constant speed of 2900 r/min or 1450 r/min, tested with air-free water at 20 °C and a kinematic viscosity of 1 mm²/s. Operate the pump within the bold performance range to avoid overheating at low flow or motor overload at excessive flow.

BLW65/80 performance curves (2900 r/min):

BLW100 performance curves (1450 r/min):

BLW125 performance curves (1450 r/min):

BLW150 performance curves (1450 r/min):

Installation Dimensions and Weights

Installation Notes

● The BLW cooling tower pump is a direct-coupled unit consisting of the pump and a custom shaft-extension motor.

● Install the pump in a ventilated, frost-free place; make sure pipe stress does not affect the pump.

● For outdoor installation, fit a suitable cover to protect the electrical components from moisture.

● The electrical installation must protect the pump against phase loss, voltage instability, overload and earth leakage.

● Leave enough space around the unit for maintenance.

● Mount the pump horizontally on a base: the horizontal direction is the suction inlet, the vertical direction is the discharge outlet.

For full performance data, installation dimensions and operating instructions, please refer to the product manual on this page.