Nordson-EFD-Series-450-Instructions.pdf - 第6页
Series 450 Autovalve / Snuff Back | Instructions / Parts Lists 6 www.nordsonefd.com info@nordsonefd.com +1-401-431-7000 Sales and service of Nordson EFD dispensing systems are available worldwide. Disassembly And Cleanin…
Series 450 Autovalve / Snuff Back | Instructions / Parts Lists
5www.nordsonefd.com info@nordsonefd.com +1-401-431-7000 Sales and service of Nordson EFD dispensing systems are available worldwide.
Maintenance (continued)
The following options are available:
A. Chemical Compatibility with O-Rings
Usually the adhesives do not chemically attack the O-rings. However, during cleaning the valves are often immersed in
aggressive solvents. The following types of O-rings are available:
Type of O-Ring Color Recommended for Contact With...
Viton
®
Green or brown
• Methylene Chloride
• Alcohol
• Carbon Tetrachloride
EP Black
• MEK
• Ketones
• Acetone
PTFE Clear / orange
• All chemicals
• Encapsulated
B. Selection of Lip Seals
The lip seal consists of a U-cup with an interior O-ring. The following types of lip seals are available:
• Polyurethane U-cup with an interior Viton O-Ring. Good general purpose seal with good chemical and wear resistance.
U-cup colored orange with a brown Viton O-Ring. Recommended for filled abrasive adhesives.
• Viton U-cup with an interior Viton O-Ring. Good chemical resistance, but it is a soft seal with poor wear resistance.
U-cup colored black with brown O-Ring.
• UHMPE U-cup and an interior SS Spring. Excellent chemical and wear resistance. U-cup colored white with SS Spring.
Other combinations available upon request.
C. Chemical Compatability
The “A” or “B” resins can attack the seal material. An attacked seal will swell or become brittle in 3 to 14 days. If this occurs,
choose an alternate seal material. Listed below are the general guidelines.
For specific recommendations for Meter Mix Dispensing, contact our Technical Service Department at 800-556-3484.
Part #7702281 (Polyurethane)
Color: Orange
Epoxies — General
Polyurethanes
Polysulfides
Part #7702277 (UHMPE)
Color: White
Epoxies — Amine Catalyst
Polyesters
Acrylics
Series 450 Autovalve / Snuff Back | Instructions / Parts Lists
6 www.nordsonefd.com info@nordsonefd.com +1-401-431-7000 Sales and service of Nordson EFD dispensing systems are available worldwide.
Disassembly And Cleaning
1. Remove the manifold and seat plate (8). Pry bar slots are provided.
2. Remove the air cylinder bolts (2) and wiggle the air cylinder apart. If
the assembly is frozen, use the pry bar slots on the valve body (7) to
separate the valve body (7) from the tie plate (5). Insert flat pieces of
metal between the valve body and the tie plate as per Figure 1. Thread
the manifold screws (36) into the back of the tie plate and push the
valve body apart. Apply uniform pressure to prevent the body from
cocking and bending the spool valves (75).
3. Once apart, the parts should be cleaned. We recommend overnight
soaking in suitable solvent. All parts can be soaked except the handle
and air cylinder.
Rebuilding the Autovalve
1. After cleaning, inspect the following components:
a. Spool valves (75) for wear
b. Lip seals (3) — both outside and inside lip
c. Manually retract and extend spool valves from air cylinder (1).
d. If the optional handle is used, connect air into the inlet and check 4-way action of cartridge valve (103).
2. Lubricate lip seals (3) and shafts (75) with auto grease.
3. Insert four back lip seals (3): two into tie plate (5) and two into the valve body (7). The lip seals are two piece: an O-Ring
and U-cup. They should always be installed with the O-Ring facing the material inlets (body of the valve).
4. Insert two front lip seals (3) that are located in the seat plate (8). They should be installed with the O-Ring facing the back
of the valve (facing the air cylinder). Optional Installation: With O-Ring facing manifold. Used when minimum snuff-back
is required. However, reduced seal life can be expected.
5. Insert O-Rings (6) and assemble air cylinder (1) and valve body (7). and the valve body (7) and engage the screws (2).
6. Push seat plate (8) through spool valves (75) and tighten bolts (9).
Final QC Check
Before the manifold is assembled, we recommend the following procedure:
1. Check the open and close movement of the spool valves (75).
2. Check gap between seat plate (8) and spool valve (75). Refer to Figure 2 when spool valves are in open position.
3. Check front lip seals by pressurizing the valve body (7) and applying soapy water into the front seals. The valve body can
be pressurized by connecting air into the A and B inlet ports on the valve body.
4. Seat plate (8)
Manifold
screws
Tie plate
Metal
plate
Air cylinder
Valve body
Figure 1
Maintenance (continued)
Series 450 Autovalve / Snuff Back | Instructions / Parts Lists
7www.nordsonefd.com info@nordsonefd.com +1-401-431-7000 Sales and service of Nordson EFD dispensing systems are available worldwide.
P/N Ref. # Qty. Description
7702265 1 1 Single Air Cylinder 5/16" stroke with Hardened SS Shafts
— 2 2 SHCS 10-24 x 2" long for 450 Series
— 3A 6 Lip Seal: Viton U-cup and Viton O-Ring
7702281 3B 6 Lip Seal: PU U-cup and Viton O-Ring
7702280 3C 6 Lip Seal: PTFE U-cup and PTFE O-Ring
7702277 3D 6 Lip Seal: UHMPE U-cup and SS Spring
7702268 4 2 Grease Fitting, 10-32
7702270 5 1 Aluminum Tie Plate
— 6A 6 Viton O-Ring
7702810 6B 6 EP O-Ring
7702275 6C 6 PTFE Encapsulated O-Ring
7702284 7A 1 AlumBody 9/16-18 Inlet Ports for 450 Valve
— 7B 1 SS Body 9/16-18 Inlet Ports for 450 Valve
7702288 8 1 Stainless Steel Seat Plate for 450 Valve
— 9 2 Stainless Steel SHSS 1/4" Dia x 1 1/2" long for 450 Valve
— 10 2 Assembled Air Tube and Fitting 10-32 Thread
7702364 11 1 Auto Grease 3 oz Cartridge (not shown)
7702372 12 1 Grease Gun 3 oz Cartridge Complete (not shown)
— 13 1 Adjustment Screw Driver for 450 Valve
NOTE: The O-rings in the lip seals face
the body (item 7). For proper alignment
see page 6. Consult factory for
additional seal combinations.
Maintenance (continued)