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CAT 314C HYD thumb pressure

One guy construction ยท 2021-03-31 14:10

I added a 360 grapple to my machine. I installed to valves and QD for the bucket curl function to make the claw operate and used the thumb function for swivel action. I used standard QD flat face like is on my CTL. Problem I have is i must crack the fittings loose to hook and unhook all the lines as there is always pressure in lines. Is there a way to relief pressure or would wing nut fittings work? thanks

Replies9
  1. #1One guy construction2021-03-31 14:11

    KJA00152 IS SERIAL NUMBER

  2. #2heymccall2021-03-31 14:16

    They make a male FF with a connect under residual pressure option. It is physically longer. Myself...I added brass bleeder on the valves for my hammer connections. Can you add a run Tee with a bleeder on each circuit?

  3. #3lantraxco2021-03-31 21:53

    Brass bleeder okay on the tank line, but you wouldn't need one there. On the pressure lines, good way to die. IMO, don't do it. high pressure steel ball valve or needle valve would be acceptable.

  4. #4heymccall2021-03-31 23:07

    Seriously? I've had brass bleeders on the auxiliaries on every hoe bigger than 10 tons here for the last 20+ years. You do understand pressure vs surface area, right?

  5. #5lantraxco2021-03-31 23:12

    YES. Do you understand pressure versus tensile strength??? Do what you like, just voicing my opinion.

  6. #6heymccall2021-04-01 00:29

    I apologize for my snide remarks there. It was certainly uncalled for. I just can't see why they shouldn't work. I suppose opening one while operating would create a hazard, but, I've never had one ever blow out. I cropped out a broken one in the above image, and I've had them all sheared in some fashion, including fully flush, not just with the wing knocked off, and never had a leak. And mind you, most of my reliefs are set at 2900psi, flows run up to 80gpm, and the shock loading from hydraulic breaker operation certainly goes higher.

  7. #7lantraxco2021-04-01 00:52

    And I don't mean to come off like the voice of doom, I may have overreacted. But honestly, the manufacturer typically rates those drain cocks as 150psi working pressure! They're made for water tanks and air systems basically. It's a hell of a testament to their strength you've had good service from them with that kind of working pressures!

  8. #8AzIron2021-04-01 01:03

    That or a stucchi style quick coupler there a little more expensive than flat face but they can couple at rated pressure you just use a wrench to thread them together I am in the process of switch ring my stuff over

  9. #9Ollie2021-04-04 18:50

    Are u running a rocker thumb switch to operate it if so leave the dummy leaver up turn machine off right before it stops activate the rocker switch should see hyd lines relive pressure