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Clickable index
Contents
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 Watson-Marlow Bredel are suitable for use in hazardous environments; ATEX compliant pumps from the 300 series are listed below, in Section 2 "Pump models".
All of Watson-Marlow's ATEX pumps have been rated as Group II, Category 2 equipment. The 313 and 314 ATEX pumphead range is intended for use in gas based environments only. The pumpheads are sold individually (for use with customer specified ATEX drives) and in defined configurations complete with Watson-Marlow ATEX drives.
This document provides specific ATEX information and should be used in conjunction with the original user manual.
2. Pump models
The following 313/314 pumpheads are covered by this manual:
313 and 314 ATEX pumpheads |
| 313DA* | 033.3411.A00 | 3 roller, tongued drive fitting for 1.6mm wall tubing |
| 313BA* | 033.3421.A00 | 3 roller, bareshaft fitting for 1.6mm wall tubing |
| 313XA* | 033.3431.A00 | 3 roller, extension head for 1.6mm wall tubing |
| 313XBA* | 033.3441.A00 | 3 roller, bareshaft extension head for 1.6mm wall tubing |
| 313D2A* | 033.3511.A00 | 3 roller, tongued drive fitting for 2.4mm wall tubing |
| 313B2A* | 033.3521.A00 | 3 roller, bareshaft fitting for 2.4mm wall tubing |
| 313X2A* | 033.3531.A00 | 3 roller, extension head for 2.4mm wall tubing |
| 313XB2A* | 033.3541.A00 | 3 roller, bareshaft extension head for 2.4mm wall tubing |
| 313B2A* | 033.3521.AM0 | 3 roller, Manesty bareshaft fitting for 2.4mm wall tubing |
| 313XB2A* | 033.3541.AM0 | 3 roller, Manesty bareshaft extension head for 2.4mm wall tubing |
| 314DA* | 033.4411.A00 | 4 roller, tongued drive fitting for 1.6mm wall tubing |
| 314BA* | 033.4421.A00 | 4 roller, bareshaft fitting for 1.6mm wall tubing |
| 314XA* | 033.4431.A00 | 4 roller, extension head for 1.6mm wall tubing |
| 314XBA* | 033.4441.A00 | 4 roller, bareshaft extension head for 1.6mm wall tubing |
| 314D2A* | 033.4511.A00 | 4 roller, tongued drive fitting for 2.4mm wall tubing |
| 314B2A* | 033.4521.A00 | 4 roller, bareshaft fitting for 2.4mm wall tubing |
| 314X2A* | 033.4531.A00 | 4 roller, extension head for 2.4mm wall tubing |
| 314XB2A* | 033.4541.A00 | 4 roller, bareshaft extension head for 2.4mm wall tubing |
* NB: these pumpheads are compatible with a number of Watson-Marlow cased drives. However, the Watson-Marlow cased drives are not ATEX-compliant.
Any 313 or 314 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 pumpheads are classified as Group II, Category 2 equipment under the definitions 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 sufficient 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 pumpheads must not be used in the underground parts of mines, and in surface installations of such mines, likely to become endangered by firedamp 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.
4. Operating parameters
The following tube materials can be used with 313 and 314 pumpheads. Bore sizes range from 1.6mm to 8.0mm, with an option of 1.6mm or 2.4mm wall thickness:
Tubing - working temperature range |
Marprene | 5C to 80C |
| Bioprene | 5C to 80C |
| Peroxide-cured silicone | -20C to 80C |
| Pumpsil platinum-cured silicone | -20C to 80C |
| Sta-Pure | 0C to 80C |
| Chem-Sure | 0C to 80C |
| Neoprene | 0C to 80C |
| PVC | 20C to 60C |
The following parameters define the boundary of the safe working envelope - these values must not be exceeded (ATEX compliance will be invalidated).
313 and 314 pumpheads |
Operational temperature range | -20C to 80C |
| Max. peak pressure (0.5 to 4.8mm bore) | 2 bar |
| Max. peak pressure (6.4 to 8.0mm bore) | 1 bar |
| Max. continuous speed, 313 | 400 rpm |
| Max. continuous speed, 314 | 300 rpm |
| Max. intermittent speed | 600 rpm |
| Corrosion resistance | see Section 7 - Materials |
| Tube life | see Section 5 - Tube failure |
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 pumphead hazards
As part of the requirements of 94/9/EC all potential hazards, including expected malfunctions, have been identified 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 modifications, the changes include additional operating instructions in order to specifiy 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 fluid |
| Mechanical failure of rotor hub |
| Exothermic chemical reaction |
| Electrostatic discharge |
| Bearing failure |
WARNING: There is potential for the fluid to be charged during pumping and subsequent flow through tubing/pipes. Please refer to BS5958-1:1991, or similar, in order that the appropriate protective measures can be implemented.
6. Installation guidelines
Please refer to the standard 313/314 pumphead manual (PB0210) for general installation instructions.
The 313/314 pumpheads achieve ATEX II 2 G c IIB T4 equipment compliance for electrostatic discharge from non-conductive parts without modification. This is because the 313/314 pumphead projected surface area in any direction is less than 100cm². EN13463-1:2001 par 7.7.4 for Gas Group IIB equipment states that there is a danger of electrostatic charge under normal conditions of use for equipment with greater surface area than 100cm².
The effect of this is that a MAXIMUM OF TWO 313/314 PUMPHEADS can be used in a ganged, multi-channel, Group IIB equipment configuration.
If the tubing, external to the pumphead, comes into dynamic contact with another surface or is in proximity to an electrical/magnetic field, the tubing could become electrostatically charged. Tubing should be positioned to prevent this from occurring.
The torque requirement for 313/314 ATEX pumpheads is 2.2Nm under worst-case conditions. A drive unit should be selected that can safely generate this torque below any overload condition. All Watson-Marlow close-coupled drives have been configured in this way and are available with thermistors for thermal overload protection.
7. Tube life
There are a number of factors that contribute to the life of the tubing:
Factors influencing tube life |
Normal tube fatigue - dependent on tube size and material |
| Incorrect tube loading - see 313/314 pumphead manual (PB0210) for guidance |
| Excess working pressure - see Section 4 "Operating parameters" |
| Chemical incompatability - a table of tubing compatibility can be found on http://www.watson-marlow.com/wmb-gb/p-chem-a.htm. Immersion kits are available from Watson-Marlow for testing. |
For each application it is strongly recommended that tube life should be determined by trials, prior to installation in a hazardous environment.
8. Potential hazards
If this is not possible, or if there is any doubt in terms of tube life, then the following hazards should be recognised before installing a pump in a potentially explosive atmosphere:
Chemical reaction between pumped fluid and pump materials - the materials of construction are listed in Section 10 |
| Pumped fluid can be ignited by surface temperature of rollers - all Watson Marlow's ATEX equipment has been rated as T4 (meaning that even under worst-case operating conditions the maximum surface temperature will not exceed 135C) |
9. Servicing and cleaning requirements
If aggresive liquids are spilled onto the pumphead, the pumphead should be removed and cleaned with a mild detergent. Remove any tubing from the pumphead.
The same cleaning procedure should be used to limit the build-up of dust (which can become electrostatically charged and/or heated by friction).
The moving parts of the rotor should be checked from time to time for freedom of movement. Rollers should be lubricated occasionally with Teflon lubricating oil.
The rotor shaft runs on sealed bearings which do not require lubrication.
10. Materials of construction - 313/314 pumpheads
Description | Part No. | Material | Finish |
Body - rear | DE1601M | PPA IXEF 1022 | |
Body - front | DE1602M | PPA IXEF 1022 | |
Track | DE1604M | PPA IXEF 1022 | |
Lever | DE1605M | PPA IXEF 1022 | |
Locking lever | DE1606M | Nylon 66 (30% glass fill) | |
Clamp - tube | DE1607M | PPA IXEF 1022 | |
Rotor | RM1610M | Nylon 66 (30% glass fill) | |
Roller | DE1612T | Nylatron GS | |
Adjuster - tube clamp | DE1608M | Nylon 6 | |
Knob - tube clamp adj | DE1609M | Nylon 6 | |
Clamp - tube 313/314 | DE1620M | PPA IXEF 1022 | |
Plate - adaptor | DE1615M | PPA IXEF 1022 | |
Spindle | DE1614T | BS970.230MO7PB (EN1A) | Nickel plate |
Shaft | DE1613T | Stainless steel 303S31F9 | |
Ball bearing | BB0014 | Steel (1% carbon, 1.5% chromium) | |
Bearing | BB0049 | Sintered bronze | |
Spring | SG0011 | Stainless steel | |
Pin - Groverlok | FN2500 | Mild steel | |
Screws |
| Stainless steel | |
Nuts |
| Stainless steel | |
Screw - Plastite 45 | FN0299 | Mild steel | Zinc plate |
The above materials have been carefully selected and have a well proven track record. However, if there are any aggressive chemicals present then it is imperative that a risk assessment is conducted. This must not be limited to just the pumped fluid but should also include any other aggressive fluids in the intended operating environment.
11. Summary of modifications
ATEX features of the 313/314 pumpheads |
| ATEX label | This is a requirement of the Directive and includes the ATEX
rating for the pumphead (Group II Category 2 for gas, T4) |
| ATEX manual | This is an addendum to the existing manual
and includes ATEX specific information |
12. ATEX marking
The 313 and 314 ATEX (A) pumpheads have been marked with the following labels:
13. Replacements
Spares and replacements should be ordered through Watson-Marlow Bredel pumps or through an offical representative. Only Watson-Marlow spares and replacements should be used in order to guarentee continued compliance with the ATEX directive.
Watson-Marlow's policy is to provide spare parts for all products for a minimum of 7 years from discontinuation. The ability to implement this policy is not entirely within Watson-Marlow's control and cannot be guaranteed, but every effort will be made to honour this policy.
Watson-Marlow Bredel Pumps can be contacted at:
Watson-Marlow Bredel Pumps
Falmouth
Cornwall TR11 4RU
England
Tel: +44 (0)1326 370370
Fax: +44 (0)1326 376009
Email: support@watson-marlow.co.uk
Web: www.watson-marlow.com
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