1. R
WEIR TYPE A
DIAPHRAGM VALVES
P.O. Box 5064, Benoni South 1502, South Africa
Tel: +27 (11) 748 0200 Fax: +27 (11) 421 2749
Email: sales@dfc.co.za Website: www.dfc.co.za
Printed June 2009

2. R
Weir Type “A” Diaphragm Valves
Handwheel- 1. Valve Flow - 2. Valve usable in any position - 4. Maintenance -
Comfortable, easy, to use for fast Pocketless design for For greater planning, flexibility Three part design ( bonnet (1), diaphragm (2),
operation. Saves time and effort contamination free and ease of access. In the hori- body(3) means the diaphragm is replaced with
Saunders Type “A” diaphragm valves have been performance and smooth zontal plane at 15° angle (flanges the body in the pipeline, no gasket costs or
Other Methods of Operation - flow characteristics. can be drilled to suit) the valve is pipeline disturbance problems are involved.
developed to handle more fluids and gasses than self-draining.
any other valve. A wide choice is available for Fast acting levers, pneumatic and electric corrosive applications
actuators - versatility to match individual
materials,methods of operation and body end
needs throughout the plant, without over
connections to satisfy the needs of most industrial investments. Ask for information on 3. Lubrication -
applications. Extended life, reliability, safety and our Biman Pneumatic actuators. Strong and resilient, giving positive shu
ease of use, combined with an essentially simple Bonnet assembly lubricated for long life.
The indicator lip seal stops the ingress Designed to assist flow and completely
design, result in low maintenance for minimum of dust, dirt and atmosphere. isolate working parts from line fluids.
running costs. Both on pressure and vacuum, Indication - (Std to Dn150)
Saunders Valves operate and close 100% leaktight. (Optional > D200) 5. Bonnet options -
Positive identification of valve position to Padlocking to and synthetic rubbers, nitrile,
Natural prevent expensive
save time and money. interference. Microswitch and ptfe faced. Al
butyl, viton, hypalon model
for valve position indication systems. security and
give maximum processing
Sealed to handle toxic or corrosive
Stem - fluids with even greater safety.
of hygiene. Special diaphragms are
Designed to reduce friction for low produced for fire fighting, tank cleaning
Body End Connections - operating torque and washdeck services to comply with
Screwed, flanged end connections
to suit UK, European, USA
Sealing -
specifications to avoid planning problems.
Operating mechanism (stem and Weir design reduces diaphragm travel
compressor) isolated from service and for extended service and fine control.
atmosphere, avoids the need for exotic
metals. Fully sealed option available for
Body End Connections -
corrosive applications
Screwed, flanged and weld end
Body Linings and Coatings: EFTE: Body materials: Linings -
connections suit UK, European, USA
100% leaktight performance guarantees profitable investment Diaphragm - Base materials cast Grey and SG iron. High abrasion resistance for tough services Cast iron and specifications to avoid planning proble
SG iron for strength and low cost
For purity, abrasion and corrosion
especially in fine chemicals, pharmaceuticals on non-corrosive duties. Acid resisting bronze and
Strong and resilient, giving positive shutoff. Polypropylene: and petrochemicals. gunmetal long life in hostile, corrosive water
metal costs.
GUIDE TO BODY (LININGS) APPLICATIONS RANGE AVAILABILITY Designed to assist flow and completely Combines strength and abrasion resistance
applications. Stainless steel-purity for services
isolate working parts from line fluids. Halar Coating: where profits depend on product protection.
0 for long service on chemical processing,
BODY / LINING TYPICAL APPLICATIONS SIZE TEMP C Solid hard rubber and polypropylene minimum
water treatment and effluents. Resists many industrial chemicals and additionally weight combined with strength
Cast Iron Strength, low cost non corrosives DN15 - DN350 -200to 175 0 Diaphragm Materials- protects the exposed parts of value bodies - resistance, smooth flow-without exotic
Ductile Iron (SG) Rubbers: to cut out painting.
0 0
Natural and synthetic rubbers, nitrile, (Hard, soft, butyl, neoprene);
A R Bronze / Gunmetal Long life in hostile, corrosive water applications DN20 - DN150 -30 to 175 Borosilicate Glass Coating:
Stainless Steel Purity of service, protect protection
butyl, viton, hypalon and ptfe faced. All Corrosives and abrasives handled with
give maximum processing security and, low initial outlay. Popularity of rubber Purity, smooth flow (especially on viscous fluids)
Rubbers Economic handling of corrosive & abrasive media DN15 - DN350 0
-10 to 85
0 linings results in exceptional availability with great strength and resistance to chemical attack
where required, food industry standards
- Soft (SRL/AAL) Abrasive duties 0
-10 to 85
0
- Hard (Ebonite) (HRL) Acid, chlorinated water, moist chlorine 0 0
of hygiene. Special diaphragms are
-10 to 110
- Butyl (BL) Mineral acids, & slurries 0 0 produced for fire fighting, tank cleaning
-10 to 105
and washdeck services to comply with Guide to Diaphragm Applications: Range availability
- Neoprene (NL) Abrasive duties where hydrocarbons are present
0 0 international standards
Polypropylene Chemical & abrasion resistance in water DN20 - DN150 -10 to 85 GRADE TYPICAL APPLICATIONS Size Temp. C
0
PP treatment and effluent handling Weir -
Polytetrafluoroethylene High temp mineral acids, aromatic, aliphatic and DN125 - DN250 -100to 175 0 Weir - B Acid and alkalis. Up to 85% sulphuric acid at ambient temperatures. DN8 TO DN350
PTFE chlorinated solvents Weir design reduces diaphragm travel Hydrochloric hydrofluoric phosphoric acids, caustic alkalis and many
Ethylene Tetrafluoroethylene High abrasion resistance, chemically resistant to DN20 - DN150
0
-10 to 150
0
for extended service and fine control. esters. Sea water, very low vapour and gas permeability. Inert gases -400to 100 0
ETFE strong acids & bases and many industrial gases.
0 0
B(V) DN25 TO DN350
Perfluoroalkoxy High temperature strong acid resisting applications DN20 - DN350 -20 to 175
PFA
TM 0 0
Q Abrasives, water purification brewing, inorganic salts, mineral acids. DN8 TO DN350
Halar Excellent resistance to mineral and oxidising DN20 - DN350 -10 to 150 -500to 100 0
ECTFE acids inorganic bases, salts Q (V) DN100 TO DN350
Borosilicate Glass Excellent for strong acids, halogens DN20 - DN200 -100to 175 0
TM 0 0
214/325 Highest chemical resistance to all fluids except alkali metals although -200to 160 0
Rilsan Potable water applications DN20 - DN350 -20 to 80 permeable to some, especially chlorine. Alternative backing diaphragms
available to deal with this and other applications.
Fusion Bonded Epoxy FBE Potable water applications DN25 - DN350
0
-20 to 80
0
DN8 TO DN250
Note: 214 grade has a bayonet fitting in all sizes except DN 8 and DN 10
214/226 Requiring a corresponding slotted compressor -50to 175 0
VALVE BODY TEMPERATURE / PRESSURE RELATIONSHIP 226 Paraffinic and aromatic hydrocarbons, acids, particularly concentrated DN8 TO DN350
sulphuric and chlorine applications. Not recommended for ammonia and -50to 150 0
Maximum for valves DN8 to 150
its derivatives or for Many solvents,of service conditions will determine the highest working temperature. For example 325 diaphragms ha
diaphragms are shown as a guide only. polar aspects e.g. acetone.
16
237 Good acid and ozone resistance certain chlorine services DN8 TO DN350 -100to 100 0
14
300 For hot water services applications involving steam sterilisations, therefore, DN8 TO DN350 0
-40 to 130
0
Maximum for valves DN65 & 80 screwed
PRESSURE (bar)
12
and PTFE (214) diaphragm DN8 to 150
Graph applies to whole valve performance (manual bon- ideally suited for brewing and pharmaceutical applications. For services
nets). For actuated valves refer to appropriat performance involving continuous high temperature / pressure combinations consult
10 graphs. Temperature bands for diaphragms are shown as our technical department.
a guide only. Many aspects of service conditions will de -
8 termine the highest working temprature. For example 325 300 (V) DN100 TO DN350
Maximum for valves DN200 diaphragms have given exellent performance under
6
DN250 certain conditions up to 150°C.
In larger sizes than 80mm weir type diaphragms are specially reinforced for vacuum duties and are identified by a suffix (V) e.g. Q (V).
4 DN300 All (V) diaphragms have ferrous studs and are specified for applications requiring all iron and steel construction e.g. Ammonia, acetylene.
B (V) diaphragms are available in sizes Dn 25 and larger to complete a full range of diaphragms with ferrous studs.
2 DN350
Key to grade letters / materials
TM
0
-60C 0
-40C 0
-20C 0
-0C 0
20C 0
40C 0
60C 0
80C 0
100C 0
120C 0
140C 0
160C 0
180C Rilsan is the registered trademark of ATO Chemical Products UK. B - Buty 214/226 - PTFE / Fluororubber 214/325 - PTFE/EP Rubber 300 - Butyl
TM
TEMPERATURE Halar is the registered trademark of Ausimont UK Limited Q - Natural Rubber 226 - Fluorubber 237 - Hypalon