Watson-Marlow 620RA User Manual
WATSON-MARLOW MANUALS
m-atex620ra-gb-03-PB0347-2
ATEX: Directive (94/9/EC) and
Watson-Marlow’s 620RA, 620REA,
and 620RE4A pumpheads
Section 2 o
f 3: Operating manual
cased pumps:
Contents
1 Introduction 1
2 Pumphead types 2
3 Hazardous environments 2
4 Operating parameters 3
5 Potential pump hazards 4
6 Installation guidelines 5
7 Tube life 6
8 Tube materials in
ATEX applications 7
9 Servicing and cleaning
requirements 8
10 Materials of construction:
620RA pumpheads 9
11 Summary of modications 10
12 ATEX marking 10
13 Replacements 10
14 Manufacturer’s Declaration 11
1 Introduction
Directive 94/9/EC, commonly known as the ATEX directive, carries obligations to
the person who places equipment on the market, in the EU territory, for use in
potentially explosive environments. A number of pumps manufactured by WatsonMarlow are suitable for use in hazardous environments; ATEX compliant pumps from
the 600 series are listed below, in Section 2 “Pump models”.
All of Watson -Marlow’s ATEX pumps have been rated as Group II, Category
2G IIB c T4 equipment. The 620RA, 620REA and 620RE4A pumpheads are intended
for use in gas based environments only. The pumpheads are sold individually (for
use with customer specied ATEX drives) and in dened congurations complete
with ATEX drives.
This document provides specic ATEX information and should be used in
conjunction with the original user manual.
ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 1
2 Pumphead types
The following 600 series pumpheads are covered by this manual:
620RA ATEX Pump heads
620RA* 064.0211.A00 Two rollers for max 2 bar.
Continuous tubing only
620REA* 064.0231.A00 Two rollers for max 4 bar.
LoadSure tubing elements only
620RE4A* 064.0431.A00 Four rollers for max 4 bar.
LoadSure tubing elements only
* NB: these pumpheads are compatible with a number of Watson-Marlow cased
drives. However, the Watson-Marlow cased drives are not ATEX compliant and must
not be used in hazardous locations.
Any 600 series pumpheads not listed here are NOT suitable for use in
hazardous environments (at date of issue).
3 Hazardous environments
All of Watson- Marlow’s ATEX pumps are classied as Group II, Category 2G IIB c T4
equipment under the denitions of 94/9/EC:
“Group II, Category 2 products should be designed to be capable of remaining within their operational parameters, as stated in the instruction manual, and based on
a high level of protection for their intended use, in areas in which explosive atmospheres caused by mixtures of air and gases, vapours, mists or air/dust mixtures are
likely to occur.”
Furthermore, “The explosion protection relating to this category must function in
such a way as to provide a sufcient level of safety even in the event of equipment
with operating faults or in dangerous operating conditions which normally have to
be taken into account”.
Watson- Marlow pumps must not be used in the underground parts of mines,
and in surface installations of such mines, likely to become endan gered by
redamp and/or combustible dust.
NB: where two or more items of ATEX equipment are combined, the complete
assembly shall carry the same rating as the lowest ranking individual piece of equipment.
ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 2
4 Operating parameters
The following tube materials can be used with 620RA pumpheads. Bore sizes range
from 6.4mm to 15.9mm, with 3.2mm wall thickness. LoadSure tube elements are
available in 12mm or 17mm bore:
Tubing: working temperature range
Marprene 5C to 80C
Bioprene 5C to 80C
Pumpsil -20C to 80C
STA-PURE PCS 0C to 80C
STA-PURE PFL 0C to 80C
Neoprene 0C to 80C
PVC 0C to 80C
The following parameters dene the boundary of the safe working envelope these
values must not be exceeded (ATEX compliance will be invalidated):
620RA pumpheads
Ambient temperature range 5C to 40C
Max peak pressure (continuous tubing) 2 bar
Max peak pressure (STA-PURE tubing) 4 bar
Max continuous speed 165 rpm (at 4 bar see below)
Max intermittent speed 265 rpm (at 4 bar see below)
Corrosion resistance See 7 Materials
Tube life See 5 Tube failure
ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 3
WARNING! Do not run dry for excessive periods. Roller and tubing
temperatures can exceed normal operating range.
WARNING! Do not run pumphead against a dead end condition (closed
discharge). This can lead to excessive roller and tubing temperatures and
pressures in excess of the limits in the table above.
When two or more items of ATEX equipment are combined, the permissible operating envelope will be determined by the narrowest range after considering all values
for a given parameter.
5 Potential pump hazards
As part of the requirements of 94/9/EC all potential hazards, including expected
malfunctions, have been identied and subjected to a risk assessment. In order to
prevent these ignition sources becoming effective a number of changes have been
implemented. In addition to engineering modications, the changes include addi-
tional operating instructions in order to specify correct usage in hazardous locations.
Please refer to Sections 6 - 10 for further details.
Recognised ignition sources
Surface temperatures of rollers and spindles
Tube burst and subsequent spilling of pumped uid
Mechanical failure of rotor hub
Exothermic chemical reaction
Electrostatic discharge
Bearing failure
Spring failure
ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 4
Loading...