SOP Soleniod Porting Required for Pilot Air
From PTAGISWiki
| Standard Operating Procedure
|
Subject:
| SOP Solenoid Porting Required for Pilot Air
|
Author:
| Troy Humphrey
|
Approved by:
| Don Warf
|
Contents |
Objective
The objective of this SOP is to give the reader the step by step process that is required to successfully add pilot air to 3-Way solenoids.
Scope
This SOP is for personnel responsible for the installation, maintenance or replacement of pneumatic controls for gates that require the use of a 3-Way solenoid. The 3-Way solenoid works without pilot air but is prone to failing in one direction. Pilot air assists the spool shift inside the solenoid so that the shift in either direction is less likely to fail.
Responsibilities
The personnel responsbile for performing these activeties include but is not limited to: COE maintenance personnel, PSMFC field operations personnel.
Procedure
CAUTION
CAUTION
NEVER WORK ON THE SOLENOID VALVES OR THE GATES THEY CONTROL WHILE THE SUPPLY AIR IS ON. SERIOUS INJURY COULD OCCUR.
Setup
- Tools Required
- 1/8" NPT Tap
- 1/8" Drill bit
- Drill
- Allen wrenches
- Parts Required
- 1/8" NPT nipple 1 1/2" long
- 1/4" NPT to 1/8" NPT reducer
- 1/4" NPT x 1/2" tube slip fitting
- M port or R port plug
- M5x6mm tapered plug
- Neumatics P/N 129-213
Check Pilot Air Porting
- Turn off supply air.
- Locate the regulated supply air line after isolation valve.
- Find a place in the air line where you would like to place the pilot air tee fitting.
- Cut the air line and insert the tee
- Remove the solenoid from the base.
- Check for the N Port plug. If it is not there add it.
- Check for the M and R plugs. Typically the R plug is installed but the M plug is missing.
- If the M or R plug is missing removal of the missing sides solenoid coil will be required.
Drilling and Tapping the Pilot Air Port
- If you are replacing a solenoid that already has pilot air added to the base, skip this step.
- The CA or CB port can be used for pilot air. Convenience of air line routing and aesthetics should be considered when determining which port to use for pilot air.
- Use the 1/8 NPT tap to tap the pre-drilled hole in the base.
- Avoid future solenoid problems by covering the solenoid base holes to prevent metal shavings from falling into the base.
- Care should be taken not to bind the tap in the hole.
- Drill out the dimple on the top of the solenoid base of the port you just tapped.
- The open holes on the base of the solenoid should be covered in some manner to keep metal shavings from falling into the pneumatic and electronic ports.
- When done drilling remove all metal shavings from the port.
- Install the nipple, reducer and slip tube fitting into the port.
- Install a 1/2" tube from the slip fitting to the pilot air tee.
Installing the Porting
- When changing the solenoid, the base typically stays in place. If pilot air is already added to the base you must check the M, N and R plugs in the solenoid. Typically N and R are in place and M is missing. If any of these plugs is missing one must be installed for the solenoid to function properly.
- Remove the solenoid from the base and check the porting as described above.
- Remove the blue solenoid coil from the end piece on the end that has a missing port plug.
- Remove the end piece.
- Once you have removed the screws that hold the end peice on be careful not to lose any parts as you pull the end piece away.
- Be careful of the wires that run from the main body of the solenoid to the end piece.
- Install the M5x6mm plug in the hole.
- Reassemble the end piece.
- Be careful of the wires that run from the main body of the solenoid to the end piece as you reassemble the end piece.
- Re-attach the blue solenoid coil.
- Re-attach the solenoid to the base
- Check that all fittings are tight before turning the air back on.
- Use the test button to test functionality and re-time the gates.
Typical Installation
References
- Porting of SOL.pdf - Numatics data sheet showing solenoid porting.
