Pneumatic Question On Cylinder Action

It might; it might not. It depends upon the air flowrate and the speed of closing, none of which is mentioned in the original post.

It depends, but it's always best to balance the length and diameter of the feed lines.

As PWSlack says, if there's an overabundance of air supply and pressure it won't matter, much.

Shortest line will close quickest and the two being fed off one line will be slowest.

Best to give them all their own equal length lines.

It is best to have the supply lines as close to equal length as possible. Using flow controls (meter out) on each cylinder port will provide a means to balance the velocities. I have run into this problem of binding in similar applications.

Thanks guys

That is what I thought just wanted the advice of the best.

Remember though, while you're evaluating your line lengths, fittings have length values that compound pressure drop. So a short length with a couple 90's could have more pressure drop that a much longer straight length.

As noted earlier, without air flow rates it is hard to verify BUT- your post indicates that YOU have experienced some type of problem.

EASIEST (and cheapest) solution is to change ALL close-in distribution piping to at least one size larger and terminate with reducing bushings at each device. This will eliminate ANY issue of piping-induced cylinder hang-up AND assure that ALL cylinders are seeing un-compromised pressure.

As most everyone has stated, the best way is to connect all cylinders with balanced piping.

1. The original installer probably didn't have the correct parts?
2. The original installer probably didn't care?
3. The original installer probably didn't know?
4. The unbalanced piping may not have had issues, until now?

Starting a project with the proper knowledge and parts is key to proper machine installation and operation. I have worked both sides. I have designed and built machines and I have maintained machines designed and built by others. It's very rare to get a new machine that operates 100% perfectly out of the box. Every single aspect must be adjusted to operate in YOUR environment.

1. Your AIR supply and pressure!
2. Your air quality!
3. Your electrical supply and voltages!
4. Your maintenance technicians
5. Your lubricants!
6. Your weather conditions!

However, like most of the respondents have said before and will continue to repeat!
Either get the knowledge you need or hire someone that has the knowledge needed to complete the task! You saw that there was something not quite right and you are questioning it. That is the first step to gaining the correct information. Once you have this information you can utilize it wherever you go!
Good luck

I don't think the line lengths will cause cylinder binding. Cylinders may be slightly outa sync. There'd be some sort of ball joint at the points of attachment to the bar that could cope with a bit of a twist....or not

Lube the cylinder perhaps.

Is the exhaust/vent port on the valve's muffler/filter clear? If that's blocked or restricted the cylinders may bind or stop.

I would tend to agree. The difference in the line lengths described, will not likely make much if any difference if there is enough air volume that matches the volumes of the cylinders(no size is given). Only thing that I can see that would cause any binding, is, as you say, the connection of the cylinders to the sealing bar. Normally, at least my normal, would have a clevis (or similar) end attaching to the bar, but, if the cylinder rod is attached as a rigid connection, slight variances in closing times may cause binding if the sealing bar is fully guided with close tolerances. Again, only speculation on my part as there is no diagram or photo of the installation.