Troubleshooting A Runaway Blast Pot

WHY WON’T YOUR DEADMAN SHUT DOWN?

It’s almost a certainty, that if your deadman won’t turn off, it’s due to a valve failure.

Here are the 3 most likely culprits in the order you’ll want to check them.

1. Control Valve
2. Auto Air Valve
3. TeraValve

I.  TROUBLESHOOTING THE CONTROL VALVE

To verify if it’s the Control Valve causing the issue, remove the bottom signal line from the control valve and depress the deadman.

If air flows through the signal when the deadman is released, the control valve is likely the issue.

Here’s our suggestions on a fix:

• If you have the right parts or service kit available, you’ll want to rebuild the valve. If you’re in the field however, and in a bind, we recommend removing the plunger, cleaning out the control valve, and lubricating the plunger with grease or chapstick before reassembling.  We can’t promise that will work, but it’s worth a try.

If air doesn’t flow through the signal when the deadman is released, it’s time to check the auto air valve.

II.  TROUBLESHOOTING THE AUTO AIR VALVE

To Verify if it’s the Auto Air Valve causing the issue:

• Close the Tera Valve.
• Shut off the Ball Valve to isolate the air currently exhausting.

If air continues to exhaust without abrasive, the Auto Air Valve is stuck in the open position due to debris or friction between the plunger stem and the assembly.

Here’s our suggestions on a fix:

• Once again, if you have a Rebuild/Service Kit you’ll want rebuild that valve.
• If in the field and in a bind, however,
  • remove the diaphragm and Puck Stem from the Auto Air Valve,
  • Disassemble and clean,
  • utilize dry lubricant for the stem,
  • re-assemble, and test.

If the air ceases then the Auto Air Valve is closing properly.

If air continues to flow however, it’s time to investigate the Tera Valve.

III.  TROUBLESHOOTING THE TERA VALVE

To verify if the Tera Valve is causing the issue, release the deadman and if abrasive streams richly out of the nozzle, without any pressure to increase velocity, the Tera Valve is not closing.

Here’s our suggestions on fixing this:

• Of course, rebuild the valve if you have a kit.
• But if you’re in the field with no kit…
  • Disassemble the valve.  Dust and Debris could be causing the plunger to stick open.
  • Clean out and spray dry lubricant on the plunger. Do not use grease, because it can cause more of a build up.

If the abrasive flow STOPS – then both the Tera Valve and Auto Air Valve are working appropriately.

If the abrasive flow DOESN’T STOP – it’s indication of bigger problems.  Give us a call.