rotary airlocks - customvac...1-b: airlocks & rotary seals the terms ‘airlock’, ‘rotary...

- Walinga -

- Rotary Airlocks -

Operator & Maintenance Manual

Walinga Airlock Manual Ver-05 2015-07

customvac.com.au [email protected]

PO Box 2426, 24 Molloy St

Toowoomba QLD 4350

P. 07-4634-7344 F. 07-4634-7606

FREECALL 1800 242 699

Agri-Vac Grain Conveyors – Walinga Feed Trailers & Blower Systems – Stored Grain Aeration

~ ~ ~ ~ ~ ~ ~ ~

- Walinga Rotary Airlock -

- Operator & Maintenance Manual -

Models 1314-4”, 1314-5” & 1618-6” 1618-7” Blow-Through

Models AL1314-DT & AL1618-DT Drop-Through

Page

1. INTRODUCTION 1

a) Principle of Operation

b) Airlocks & Rotary Seals

2. TECHNICAL SUPPORT 1

3. KEY OPERATING GUIDELINES 2

a) Direction of Rotation

b) Tip Clearances

c) Flexible Tip Wiper

d) Rotor bearings

4. SCHEDULED MAINTENANCE 3

a) Commissioning Period

b) Maintenance Recommendations

5. TROUBLESHOOTING 4

a) Rotor Grinds during Operation

b) Airlock Stalls or Motor Overloads

c) Air Blow-Back Restricts Feed Inlet

d) Flexible Tip Wiper Breaks

6. AIRLOCK MAINTENANCE 7

a) Typical Blow-Thru Airlock Parts

b) Tools for Adjusting Blade Wear-tips

c) Replacing Damaged Blade Tips

d) Adjusting Wear-tip Clearances 9

e) Rotor End Clearance

(f) Out-of-round Casing

(g) Checking for Out-of-Round Wear

Walinga Airlock Manual Ver-05 2015-07

Typical Blow-through Walinga Airlock

Walinga Airlock Manual Ver-05 2015-07 P a g e | 1

- Walinga Rotary Airlocks -

Models 1314-4”, 1314-5” & 1618-6” Blow-Through


1. INTRODUCTION

1-a: Operating Principles Walinga Models 1314 and 1618 Rotary Airlocks use a multi-bladed rotor to meter material. The rotor picks up material in the pockets between blades as it rotates past the top feed inlet area. It then transfers this material through the airlock casing to either a ‘blow-through’ or ‘drop-through’ area at bottom of casing . Walinga airlocks usually include low-clearance wear tips on each rotor (some special-purpose airlocks have single-piece/non-adjustable blades). Wear tips are adjustable & replaceable, and usually made of high-wear stainless steel or ‘hardox’. Other tip materials and designs may be used for specialised applications. The tips deliver a high degree of sealing between the material supply chamber and the outlet area. During operation the multi-bladed rotor fills with material at the inlet (top) side of the unit. This material moves with the rotating blades and drops through to either the ‘blow-through’ or ‘drop-through’ chamber below. ‘Blow-through’ designs use a pressurised air-stream entering the inlet port to move material through the chamber to a pneumatic transfer line connected to the outlet port. ‘Drop-through’ designs drop the product out of the airlock under gravity through a large rectangular discharge port under the unit.

1-b: Airlocks & Rotary Seals The terms ‘airlock’, ‘rotary valve’ and ‘rotary seal’ are sometimes used to describe the same item of equipment. In general an ‘airlock’ provides a higher level of sealing and is more easily adjusted than a ‘rotary seal’. Their heavy duty cast construction and high level of sealing suit them well to commercial applications – especially when using pressurised delivery line.

2. TECHNICAL SUPPORT Customvac staff are available for technical support both before and after installation. Contact us by phone, fax or e-mail during installation, operation or maintenance.


3. KEY OPERATING GUIDELINES

3-a: Direction of Rotation The airlock rotor MUST MOVE ANTI-CLOCKWISE ... when viewed from DRIVEN-END. This means that blades MUST rotate INTO the flexible tip wiper. Do not operate for extended periods in reverse direction.

Prolonged operation in reverse direction of rotation results in high wear rates in the casing and loss of performance.

Operating for short periods in reverse direction is acceptable but only to assist in clearing objects jammed between the blades and casing. Reverse operation also increases product damage because the flexible tip wiper is not effective when the rotor moves in a clock-wise direction (viewed from the driven end).

3-b: Tip Clearances An adjustable wear-tip is attached to the outer edge of each rotor blade. These tips provide a seal as the rotor transfers material from the intake to the outlet area. Efficient operation requires a close fit between the top of each blade tip and the airlock casing. Excessive clearance allows ‘blow-back’ of air through the airlock causing uneven flow and reduced performance.

~ Check & adjust wear-tip clearances regularly ~ - see Section 6

Routine maintenance of tip clearances is especially important in materials with high abrasion characteristics – for example, paddy rice.

3-c: Flexible Tip Wiper The intake chamber has a flexible tip wiper bolted to the left hand side (viewed from the driven end). The tip wiper levels material as it moves out of the intake area into the casing. This levelling action ensures even flow, reduces wear rates and avoids ‘out-of-round’ wear within the casing.

~ Check flexible tip wiper regularly - see Section 6 ~

3-d: Rotor Bearings Each rotor shaft bearing is housed in a sealed grease box and does not require routine lubrication. Remove the cover plate only if operational problems are suspected. Ensure that the grease box is fully packed with grease before replacing the cover.


4. SCHEDULED MAINTENANCE The intervals suggested on the schedule below are typical only. Adapt it to suit your existing scheduled maintenance program.

4-a: Commissioning Period Perform commissioning checks within the first 2 hours of operation and again within 10 hours. Step through the ‘500 hour’ maintenance items at both the 2 hour and 10 hour commissioning checks.

4-b: Typical Maintenance Checklist

Typical Interval Maintenance Items

Every:

- 500 hours total operation or

- 500 tonne wheat equivalent or

- 3 months intermittent operation

which-ever occurs first.

(1) Tighten Bolts/fasteners (2) Adjust drive tension/alignment & lubricate if necessary (3) Listen for excessive noise from bearings and rotor (4) Check temperature levels around bearings/drive motor/rotor casing (5) Inspect for air leaks at all inlet and outlet flanges.

Every:

- 2000 hours total operation or

- 2000 tonne wheat equivalent or

- 12 months intermittent operation

which-ever occurs first

(1) Inspect wear tips on blades and replace if damaged (2) Inspect flexible tip wiper and replace if damaged (2) Adjust clearances on all blade tips (See Maintenance Section for procedure)


5. TROUBLESHOOTING The Walinga airlock delivers long periods of trouble-free operation when operated and serviced correctly. This trouble-shooting guide will help you identify and solve a range of operating issues that may occur.

- WARNING - ISOLATE THE AIRLOCK FROM YOUR POWER SUPPLY BEFORE CLEARING OR ADJUSTING

Trouble-shooting

5-a: Rotor Grinds During Operation

(1) Rotor Blade Tips not fully seated after adjustment.

Alight grinding noise may be heard for several hours after adjustment of the airlock tip clearances. This noise will normally disappear after the tips seat fully on the casing.

If the noise is excessive the tips may be adjusted too tight against the casing. Re-adjust tip clearances as described in the Maintenance section.

(2) Incorrect Direction of Rotation

The airlock is designed to operate continuously in one direction only. Check that the shaft rotates in an anti-clockwise direction when viewed from the driven end of the unit. Continuous operation in reverse will cause excessive wear and may damage the rotor tips, tip wiper, casing and bearings.

(3) Bearing Failure Remove bearing cover plates at each end of the airlock. Follow normal bearing replacement practices and ensure that the bearings and housings are fully packed with grease before replacing covers. Always re-check clearances between end of rotor blades and end plates after replacing bearings. See maintenance section for guidance.


Trouble-shooting

5-b: Airlock Stalls Or Motor Overloads

(1) Obstruction in Airlock Prevents Blade Rotation

(a) Units with Reversible Speed Controller: Change the rotational direction of the airlock briefly then return to correct direction. Repeat this several times until the object (for example, bolts or metal) falls sideways into the blade area and clears. If this fails, move to (b)…

Caution: Changing the direction of rotation by reversing the wiring on 3-phase electric motors is not recommended. Impact damage may result.

(b) Units without reversible speed controller: Isolate the power supply to the unit - ESSENTIAL! Remove obstruction manually. You may gain access through an inlet or discharge opening (after removing piping or ducting) or via an inspection hatch if provided in your installation. If still unable to clear you will need to remove the complete airlock unit for attention.

(2) Prolonged Operation in Reverse Direction

The Walinga airlock operates in an anti-clockwise direction when viewed from driven end. Damage to rotor blades and tips due to prolonged operation in the opposite direction may cause jamming. The unit may need to be removed to assess rotor and casing damage – repair or replace.

(3) Tip/Casing Clearances too Tight

Re-set clearances between blade tips and casing as described in maintenance section.

(4) Drive-line adjusted Incorrectly

If fitted with chain/sprocket drive check tension, alignment and flexibility of links.

(5) Faulty Drive Motor

Service drive motor.


Trouble-shooting

5-c: Air Blow-Back Restricts Feed Inlet

(1) Blade Tips and Casing

Remove airlock and adjust tips to correct clearance as described in maintenance section.

Excessive clearance causes operating problems including bridging and erratic flow. Prolonged operation with high clearances wears the casing unevenly - this will result in lower performance even after adjustment of tips.

(2) Airlock Casing not Pressure-vented

Note: Pressure Venting improves the flow of ‘light’ materials into the airlock. May not be necessary for all applications.

(a) Check whether a vent line is fitted to one of the airlock end plates

(b) If fitted, remove & check that vent piping/flex is clear - clean if necessary.

(c) If not fitted, contact Cstomvac for details of a suitable end-plate venting kit

If flow improves fit a pressure-vent kit. Components are available from Customvac Australia Pty Ltd.

5-d: Flexible Tip Wiper beaking/wearing rapidly

(1) Rotating in Reverse

Airlock rotor must move in anti-clockwise direction when viewed from driven end. Change direction and service tips or flexible tip wiper if necessary.

(2) Tip Wiper Fouling on Blade Tips

Re-adjust clearance of flexible tip wiper - see Maintenance Section


6. AIRLOCK MAINTENANCE

Wear-tip and tip-wiper-blade adjustment are essential scheduled maintenance items to ensure efficient operation. Excessive clearances between rotor tips and airlock casing will reduce performance and increase both the rate and non-uniformity of wear.

6-a: Typical Assembly/Parts - Blow-through Airlock Appearance will vary with model

Item Generic Description Qty Item Generic Description Qty

1 BOLTS 4 15 LOCKWASHERS 4

2 SEAL PLATE W/ SEAL 1 16 NUTS 4

3 SEAL 1 17 CHEVRON GASKET 4” or 5” 2

4 LOCKNUT 2 18 CHEVRON GASKET 6” 2

5 BEARING CONE 2 19 ENDPLATES 4” or 5” 2

6 BEARING CUP 2 20 ENDPLATE 6” or 7” 2

7 O-RING 2 21 BOLTS 16

8 SHAFT KEY 1 22 URETHANE SEALS (Endplates) 2

9 SEAL (MAIN SEAL) 2 23 ROTOR ASSY 1

10 MACHINED CASING 4” & 5” 1 24 WEAR TIPS (1 per blade) 10

11 CASING MACHINED 6” & 7” 2 25 SPRINGWASHERS 50

12 TIP WIPER 1 26 CAP SCREWS ..or Hex-head fasteners

50

13 WASHER PLATE 1 27 GREASE -BOX COVER 1

14 BOLTS 4 28 BOLTS 4


6-b: Tools/Parts for Adjusting/Replacing Blade Wear-tips

• 3/8" Socket Ratchet Arm • 3/8" Socket Extension (30cm) • T40 Magna Bit Tool (Star-end) to suit Tip

Retaining Screws *

*Some airlock tips are fastened with hex

head bolts. Use standard sockets/spanners

• Wear Tip Retaining Screws (star head) &

Washers if existing screws are damaged. • 3/8" socket driver to suit T40 Magna Bit

Tool • Feeler Gauges (2 sets) or Shim Metal of

specified thicknesses

• Permanent Marker Pen • Small Pry Bar (say, 50 cm long) • 2 x 1/2" ring/open end spanner • Scraper (to remove flange sealant) • Flange Sealant (eg silicone-based) or

Gaskets. Ensure that silicone-based sealants are accepted for use in your industry.

- Parts -

T40 Bits, Tip Retaining Screws & Spring Washers are available

from Customvac Australia Pty Ltd

- WARNING -

ISOLATE THE AIRLOCK FROM POWER SUPPLY BEFORE CLEARING or ADJUSTING

6-c: Replacing Damaged Wear-tips The rectangular strip of metal fastened to each rotor blade is a wear tip - usually stainless steel or ‘hardox’ steel. If one edge of a wear tip is damaged you may be able to reverse it and use the other edge. If tips are badly damaged - replace them. Always check the condition of replacement tips before installing. They must not be bent and all four edges must be true and undamaged. (a) Loosen and remove tip retaining screws or bolts. The T40 (Star head) Magna Bit Tool will be

needed if ‘star-head’ fasteners have been fitted. Remove tip from casing – the inlet/outlet ports at bottom of Blow-Thru units may be a convenient removal point.

(b) Check length of replacement tips. File or grind the ends of replacement tips if necessary to

ensure that the tips are not longer than the rotor blades. (c) Fix tips loosely to rotor blade with tip retaining screws. Follow the adjustment method in following

section to set correct clearances between wear tip and casing.


6-e: Rotor End Clearance

Typical ‘as-new’ clearance between Rotor & each end-plate is:

Model 1314 (4” & 5”) airlock: 0.005" - 0.007” (5 - 7 thou)

Model 1618 (6” & 7”) airlock: 0.006” - 0.008” (6 - 8 thou)

Adjust using the lock nut on each end of rotor shaft if clearance drops below minimum.

End clearances will increase as the ends of rotor blades wear over life of airlock. Up to 0.010” (10 thou) clearance at each end may be acceptable, depending on application.

6-d: Adjusting Wear-tip Clearance

1. Use a marker-pen to write ‘ 1 ‘ on the first blade

DON’T mark second blade until AFTER tip on first blade is adjusted 2. Loosen wear-tip retaining screws (domed-head) on blade #1 using a T40 tool-tip or

equivalent. Use a spanner if Hex-head fasteners are fitted. 3. Rotate the blade until it is about 1 cm inside the airlock casing opposite the flexible tip

wiper. Blades are angled slightly, so one end will be further inside casing.

4. Place a feeler-gauge/ shim between wear-tip and casing 10 cm from each end of blade

> Using 2 feelers/ shims is quicker & more accurate than a single shim <

Target Clearances : 0.005" (5 thou) for model 1314 (4” & 5”)

0.006” (6 thou) for model1618 (6” & 7”)

5. Gently lever the blade upwards until it contacts the feeler gauges or shims.

6. Tighten tip screws . . . CENTRE SCREW FIRST!

7. Carefully rotate airlock rotor anti-clockwise (viewed from driven end) and listen for grating/binding noise between tip and casing. A light grinding noise is normal and will disappear as tips seat fully during first few hours of operation. Re-adjust if necessary.

8. Repeat the adjustment steps for each blade. Number each blade (i.e. #2, #3 etc) ... ....... BUT ONLY AS YOU WORK ON IT to ensure that none are missed.

9. Adjust the Flexible Tip Wiper. Each tip should contact the flexible tip wiper

lightly as the rotor turns. Replace if wiper is worn excessively or damaged.

Rotor MUST rotate ANTI-CLOCKWISE (viewed from DRIVE end)

when re-connected to drive motor -


6-f: Out-of-Round Casing Wear Airlock with excessive out-of-round wear in the casing will deliver poor performance. All airlocks wear unevenly. This is because the rotor carries material down one side of the airlock, then returns empty (or near empty) up the other side. The rate of wear increases when ....

a)...abrasive material is transferred .. e.g. ‘dirty’ grain (contaminated with soil or sand) is more abrasive than ‘clean’ grain. (b)... the rotor is operated in incorrect direction of rotation.

Rotor MUST turn anti-clockwise when viewed from the shaft (driven) end.

i.e. Blades must rotate INTO the flexible tip wiper to ‘smooth’ entry of material into the casing

6-g: Checking for OUT-OF-ROUND Wear in Airlock Casing

FIRST.. Adjust wear-tips to give acceptable casing clearance on side OPPOSITE the tip wiper

Target Tip Clearances: 0.005" (5 thou) for model AL1314 (4” & 5”) airlocks

0.006” (6 thou) for model AL1618 (6” & 7”) airlocks

THEN...... Measure clearances on the INTAKE (tip wiper) side of casing

If clearances on INTAKE side are more than 0.010” on model 1314 (4” & 5”) airlocks or 0.012” on 1618 (6” & 7”) , airlock may need replacing or casing re-machined.

Airlocks must be re-machined by tool shops with experience in this type of work. Inaccurate alignment of end-plates and casing is the most common error in a re-machining job. They MUST align on the same shaft centre-line.

Endplates are often re-machined when casings are machined. Ensure that the correct distance BETWEEN the internal faces of end-plates is achieved after re-assembly.

Typical ‘as-new’ Clearance between Rotor &each End-plate

Model 1314 (4” & 5”) airlock: 0.005" - 0.007” (5 - 7 thou)

Model 1618 (6” & 7”) airlock: 0.006” - 0.008” (6 - 8 thou)


- Walinga Airlock -

Models 1314-4”, 1314-5” & 1618-6” Blow-Through


Typical BLOW-THROUGH Airlock Appearance will vary depending on design & model

rotary airlocks - customvac...1-b: airlocks & rotary seals the terms ‘airlock’, ‘rotary...

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