SMC Booster Regulator VBA43A Maintenance Manual
Document ID: VBA-MM-M009-B
1. Foreword
When the booster regulator is disassembled and reassembled for maintenance, read and follow this manual.
Maintenance period depends on air quality and operating conditions, but when either of the following situations are seen on the booster regulator, it should be considered to be close to its life end and given maintenance at an earlier period.
Conditions for maintenance:
- The handle is bleeding all the time.
- Exhaust sound can be heard at an interval of 10 to 20 sec. without air consumption at the secondary side.
Maintenance Procedure Overview:
- Start: Check that air pressure is exhausted from the IN and OUT sides.
- Preparation: Disconnect piping. The size of tool prepared for disconnection should be suitable for the type of piping.
- Removal: Remove the tank (VBAT20 and 38) from the booster regulator. For removal, use a hexagon wrench (nominal size 8).
- Disassembly: The tool prepared for disassembling the booster regulator should be as shown in "Necessary tools" of applicable pages. Disassembly in accordance with procedure from page 2 to 4.
- Replacement: Wipe off stain of sliding face and dust of mesh filter. Check the condition of parts; if any have scratch or abrasion, replace with a new one listed on page 5. If the silencer gets clogged internally, replace it as well. Gather replacement parts to one place to prevent mix-ups during reassembly.
- Reassembly: Assembly in accordance with procedure from page 2 to 4. In the end, check that there is no part and screw missed for assembly or tightening.
- Mounting: Put back the disassembled parts to their original positions.
- Inspection: Supply air, rotate the handle clockwise and set pressure. Check for external leakage with soapy water. If any abnormal phenomenon is seen, please contact SMC sales branch.
2. Maintenance of cylinder and body
2.1 Maintenance of cylinder
Necessary items
- Socket wrench, Nominal 19 (2pcs)
- Looseness preventive adhesive (Loctite 243, etc.)
Disassembly procedure
- Check air pressure is exhausted from the IN and OUT sides.
- Loosen the hexagon nuts (12) and spring washers (11) with the socket wrench, and remove three tie rods (10).
- Take off the side covers (6) at the right and left.
- Remove the cylinder tubes (6, 7) at the right and left sides.
- Loosen the piston nut (13) with the socket wrench and remove the piston.
Maintenance and check
- Check any part does not have abrasion, deterioration and deformation. If it has, replace it with new one.
- Wipe off stain from the part whose motion is not smooth, and apply grease.
- If you move onto maintenance of the body, refer to 2.2 Maintenance of body (P.3).
Reassembly
- Apply grease to the part marked with ⚙️ in Fig. 1.
- Pass the piston rod (3) through the body (1) and assemble the piston.
- Apply one drop of Loctite to the thread of the piston nut (13) and tighten it with the socket wrench (Torque 21Nm). The piston is not fixed completely (idles) if it is assembled correctly. Do not tighten it over necessary torque.
- Mount the O-rings (2) to the right and left sides of the body and assembly the cylinder tubes (6, 7). It should be noted the cylinder tube assembled is different for the right and left sides.
- Mount the O-rings to the side covers (6) and assemble the side covers to the right and left of the cylinder tubes (6, 7).
- Pass through three tie rods (10) and tighten them with the hexagon nuts (12) and spring washers (11) (Torque 42Nm).
Check
- Check the bolts and nuts are tightened to adequate torque.
- Supply air and check pressure setting can be performed.
- Check there is no leakage from connected parts with soapy water.
Figure 1 Description: This figure illustrates an exploded view of the booster regulator cylinder assembly. It shows components such as cylinder tubes (6, 7), O-rings (2), piston rod (3), piston nut (13), tie rods (10), hexagon nuts (12), and spring washers (11), detailing their arrangement for maintenance and reassembly.
2.2 Maintenance of body
Necessary tools
- Phillips driver
- Pincettes
- Turbine oil (Turbine oil 32 class 2, Exxon Mobile or like that)
Disassembly
- Remove six cross recessed flat head screws (7) at the right and left sides with the Phillips driver.
- Take off the side plates (6) at the right and left.
- Take out the check valve seat assembly (2, 3, 11) through (15) from the body (1).
- Take out the switch valves (4, 8) through (10) from the body (1).
- Take out the rod seal (5) from the body (1) with the pincettes.
Maintenance and check
- Check any part does not have abrasion, deterioration and deformation. If it has, replace it with new one.
- The end of IN port has a mesh filter built in. Remove dust from the filter by air blowing.
- Wipe off stain from the part whose motion is not smooth, and apply grease. Apply one drop of Turbine oil to the switch valve.
Reassembly
- Mount the switch valves (4, 8) through (10). (It is a precise part and should be handled with care.)
- Assembly the check valve seat assembly (2, 3, 11) through (15) to the one side, mount the side plates (6) and tighten them with six cross recessed flat head screws (7). (Tightening torque 3Nm) It should be noted the check valves (2) and (3) have different mounting direction.
- Assembly the check valves to the other side. At this time, hold down the spring to overcome its reaction force.
Check
- Check there is no gap between the side plates (6) and body (1).
- Check the springs are mounted in place and the check valves (2, 3) and switch valve (4) move smoothly.
Figure 2 Description: This figure shows an exploded view of the booster regulator body and associated components. It includes the body (1), side plates (6), various switch valves (4, 8), rod seal (5), check valve seat assembly parts (2, 3, 11, 15), check valves (2, 3), check valve springs (11), plungers (12), plunger guides (13), push rod guide assemblies (10), exhaust sleeves (9), and a mesh filter. The description highlights the arrangement and specific parts involved in the body's maintenance.
3. Maintenance of governor
Necessary tools
- Phillips driver
- Radio pliers
Disassembly
- Check air pressure is exhausted from the IN and OUT sides.
- Rotate the handle counterclockwise back to the end (one direction).
- Remove four cross recessed round head screws (9) with the Phillips driver.
- Remove the bonnet assemblies (8, 10), pressure adjusting screw (7), pressure adjusting spring (6), O-ring, governor spacer (5), and regulating piston assembly (4).
- Pull out the governor valve seat assembly (2) with the radio pliers.
Maintenance and check
- Check any part does not have abrasion, deterioration and deformation. If it has, replace it with new one.
- Wipe off stain from the part whose motion is not smooth, and apply grease.
Reassembly
- Mount the governor valve seat assembly (2) with minding the mounting direction of the body (1).
- Mount O-ring, regulating piston assembly (4), governor spacer (5), pressure adjusting spring (6), and pressure adjusting screw (7).
- Put on the bonnet assemblies (8, 10) and tighten them with four cross recessed round head screws (9) using the Phillips driver (Torque: 3Nm).
Check
- Check the cross recessed round head screws (9) are tightened and supply air.
- The governor starts relieving. Then, rotate the handle to positive direction until relieving stops.
- Check pressure setting to necessary pressure can be performed by handle.
- Check there is no leakage from connected parts with soapy water.
Note: Maintenance of the governor can be performed without removing the cylinder part.
Figure 3 Description: This figure displays an exploded view of the governor assembly. It details components such as the governor valve seat assembly (2), regulating piston assembly (4), governor spacer (5), pressure adjusting spring (6), pressure adjusting screw (7), bonnet assemblies (8, 10), and cross recessed round head screws (9), illustrating their configuration.
4. Replacement parts list
The replacement part can be ordered with the following part number. Each set includes the components shown in the right part of table. Refer to the drawing number and item number in this manual to check each part.
| Part number | Description | Component | Qty. | Dwg. no. | Item no. |
|---|---|---|---|---|---|
| KT-VBA43A-1 | Booster regulator maintenance parts set | Piston seal | 2 | Fig. 1 | (5) |
| Rod seal | 1 | Fig. 2 | (5) | ||
| O-ring (gasket) | 2 | Fig. 1 | (2) | ||
| Governor assembly | 1 | Fig. 3 | (2) | ||
| Check valve | 4 | Fig. 2 | (2),(3) | ||
| Cross recessed flat head screw (mounting screw) | 12 | Fig. 2 | (7) | ||
| Grease package | 2 | - | - | ||
| KT-VBA43A-2 | Switch valve set | Switch valve assembly | 1 | Fig. 2 | (4) |
| Exhaust sleeve | 2 | Fig. 2 | (9) | ||
| Travel spring | 1 | Fig. 2 | (8) | ||
| Push rod guide assembly | 2 | Fig. 2 | (10) | ||
| KT-VBA43A-3 | Governor valve seat set | Governor assembly | 1 | Fig. 3 | (2) |
| O-ring | 2 | Fig. 3 | (3) | ||
| Governor spacer | 1 | Fig. 3 | (5) | ||
| Regulating piston assembly | 1 | Fig. 3 | (4) | ||
| KT-VBA43A-4 | Seal set | Piston seal | 2 | Fig. 1 | (5) |
| Rod seal | 1 | Fig. 2 | (5) | ||
| O-ring (large) | 2 | Fig. 1 | (2) | ||
| O-ring (small) | 2 | Fig. 1 | (8) | ||
| Grease package | 2 | - | - | ||
| KT-VBA43A-5 | Check valve set | Check valve | 4 | Fig. 2 | (2),(3) |
| Check valve spring | 4 | Fig. 2 | (11) | ||
| Plunger | 2 | Fig. 2 | (12) | ||
| Plunger guide | 2 | Fig. 2 | (13) | ||
| Check valve guide assembly | 2 | Fig. 2 | (14) | ||
| Grease package | 1 | - | - | ||
| KT-VBA40A-6 | Bonnet set | Bonnet | 1 | Fig. 3 | (8) |
| Handle | 1 | Fig. 3 | (10) |
