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INDUSTRIAL PUMPS
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Chapter 2 - Introductory Information
Translation of original instructions -
S
CUBIC -
S
BOXER
rev
. 2021
2.4 PUMP DESCRIPTION
2.4.1
FUNCTIONING PRINCIPLES
Thepneumatic pumps of the S
CUBIC and
S
BOXER
series consist of an internal insert that directs air to the
diaphragms of the two pumping bodies by moving them via a central pin. The diaphragms integral with
the central driving pin are operated with alternating motion in two stages (suction-delivery) and constitute
the pumping elements.
The respective fluid retaining ball valves are housed between the two pumping chambers and the pump
delivery and suction ducts.
The two-stage operating principle operates simultaneously (while one chamber is in the suction phase, the
second chamber is in the discharge phase), guaranteeing negative suction, high head and the pumping of
fluids with high viscosity and solid parts in suspension
(see 2.6 CHARACTERISTICS TECHNICAL DATA)
.
2.4.2
INSTALLATION REQUIREMENTS AND FEATURES
S
CUBIC and
S
BOXER
air pumps are self-priming and can run dry and allow varying the operating speed
even during service.
They can be used for the recirculation and pumping of liquids with high viscosity and solid parts in
suspension
(see 2.6 TECHNICAL FEATURES)
. Their operation is envisioned for horizontal installations,
above and below head, with precautions compliant with the features of each model
(see 2.6 TECHNICAL
FEATURES)
.
The suction and delivery pipes can be suitably sized
(never smaller than the pump) to ensure minimum flow
rates and optimal performance.
2.5 INTENDED USE AND IMPROPER USES
2.5.1
INTENDED USE
The air-driven SCUBIC and SBOXER pumps have been designed and constructed to pump liquids and
aggressive liquids (acid or alkaline) with chemical composition and temperatures compatible with the
pump materials and apparent viscosity of between 1 and 20,000 Cps at 20°C (see the Technical Data
Sheet of the Pump model);
viscosities higher than 20,000 Cps at 20°C result in physical factors that
require correct evaluation, therefore, it is always necessary to contact the Manufacturer’s Techni
-
cal Department in advance.
The maximum temperature allowed for process fluid depends on and/or is downgraded by the construction
material of the pump and system.
CAUTION
The maximum temperature limits are based on two factors, mechanical and corrosive. Some of the flu
-
ids used may significantly reduce the maximum safety temperatures due to the high corrosive content.
Conformity
with the ATEX marking affixed on the pump is no longer ensured when the maximum
temperature is exceeded.
2.5.2
CALCULATION OF MAXIMUM FLUID TEMPERATURE
(
for Zone 1 - Zone
21)
Below is
the formula for determining the maximum permissible fluid process temperature for
S
CUBIC e
S
BOXER
pumps in CONDUCT version: II 2G Ex h IIB T4 Gb and
II 2D Ex h IIIB T135°C Db) for installation in Zone 1 - Zone 21.
Temperature Class
ATEX
Calculation Factor
(only for
Zone 1- Zone
21)
Maximum temperature of
Fluid process
ATEX
T4 - Tx 55°C = Tf 80°C