How to Upgrade From Legacy Pneumatic Components

Many established OEMs have older product offerings that have been their “bread and butter” designs for years. Over time, some of the components that make up these designs can become obsolete, have horrendous lead times, or get price prohibitive to purchase as they begin to be phased out by their manufacturer. This can be a huge thorn in the OEM’s side when there are no direct replacements available. Recently, one of my foundry equipment OEMs had this exact situation and Cross Company was able to help solve this headache for them.

First, a little background. My customer makes three sizes of a product called an impactor. It’s basically an air actuated sledgehammer with a shock-absorbing handlebar and is trigger actuated. It’s typically hoist mounted and is used by the operator to break runners, gates, and risers away from iron castings. It's almost like firing a bazooka but is much faster and easier on the operator versus using a manual 12-lb sledgehammer to break the castings off the trees.

This product has two air logic manifolds to control the actuation. The smaller manifold acts as a pilot manifold to fire the big valves on the larger secondary manifold and, in turn, the main cylinder. It then automatically resets the whole circuit. This pilot manifold is made up of a base mounted 3-way relay valve, a timer module, and a custom adapter plate to mount on the larger secondary manifold with a bottom o-ring interface.

Original Pilot Manifold | Cross Company

Original Pilot manifold

We supply the components for the trigger mechanism, the relay valve, and the timer module for the pilot manifold. Our customer sources the custom adapter plate that our valves mount to from a machine shop out of state. We didn’t design the pilot manifold, but rather inherited this business over 10 years ago. Recently, our customer has complained about several issues they are seeing with our valves.

Lead time, Inconsistent Actuation, and Pricing

The valve components we supply on the pilot manifold are made by one of our best vendors but were originally designed back in the 1970’s to be used with 50-psi air pressure. Unfortunately, these components have never been updated and there are no plans to update them by our vendor. They are rugged, but are very old designs and are no longer in high demand. This creates one of our customer’s issues: extremely long lead times! One item typically has an 8-10 week lead time, while the other is typically 4-6 weeks.

A second issue is the inconsistent behavior of some of the valves. After waiting up to 10-weeks for a batch of valves, once they receive and install them, they may or may not work properly once adjusted. The impactor cylinder needs to actuate at certain speeds to cleanly break the castings away from the runners and to meet our OEM’s rated specifications. We have returned some suspect valves back to the manufacturer for evaluation, but they always check out OK. I believe this anomaly goes back to the valves originally being designed to be used with 50-psi maximum air pressure. Our OEM’s customers are typically using 90-100-psi plant air on their impactors. This higher pressure may be causing some erratic actuation of the valves. Another possible variable could be the very old tooling used to manufacture the parts for these valves.

And the last issue is the ever increasing pricing on these older legacy valves. Because they are not used very often these days, our vendor has larger annual price increases to try to cover the costs of manufacturing low-demand 40-year-old products. This higher pricing adds costing to our OEM’s equipment, which negatively affects them as they then have to increase their pricing to their customers on their impactors.

Proposed Solution

After meeting with the customer’s lead engineer and project manager overseeing this equipment, I started investigating other possible options for them. They needed something that could easily retrofit and be a drop-in replacement since they had so many pieces of this equipment in the field.

Because of the extremely harsh vibration that this application sees (think sledgehammer!), their customers have to eventually replace these valves when doing maintenance on the equipment. Being that the adapter plate was a custom adapter with a bottom o-ring interface, and sourced by our OEM from an outside machine shop, there was no easy drop in replacement available.

After researching, I found a standard product from a smaller vendor we represent that actually combined the two valve modules into one component. This one module could address all three of their concerns (lead time, inconsistent actuation, and price). It could ship in 1 week, was rated to work with up to 150-psi air pressure, which may solve the erratic valve actuation, and pricing was much lower than the other two loose components. However, it had a much different mounting interface versus their existing adapter plate, which would not make it a drop-in by any means.

After studying their air-logic schematic in detail for this piece of equipment, I thought we could mount this new valve to a standard vendor manifold base and externally plumb it to their existing manifold just for temporary testing purposes. My OEM was willing to try it, so I ordered a valve and standard base and brought it in for testing. After some very creative plumbing and fine tuning of the timer module, we were able to cycle the impactor with very good speed and repeatability. It looked promising! Now that we knew the new valve and timer module would functionally do what we needed it to do, the big question was how could we get it to interface with the existing secondary manifold with its custom o-ring interface and offset porting?

I submitted some manifold drawings with internal porting suggestions to our new vendor. They were able to design a pilot manifold plate that would work with the valve and interface with the secondary manifold. They quoted me both a prototype price and pricing for a 50-piece run for a kit that included the valve, a gasket, and the custom adapter plate. The higher prototype pricing was only about half the cost of what they were currently paying for the three loose components! The 50-piece pricing was a good bit lower than that!

How to Handle Setbacks

At least, I thought the testing went great - until a few weeks later when I was informed of a problem that we had not anticipated. This pilot valve manifold will be used on all three sizes of their impactor units. Something we had not thought about was where the handlebar on each unit was located. We had only mounted and tested it on the most common size of the impactor. Once they tried to mount it on the other two units, we found out the handlebar went directly over the timer adjustment and we could not get to the adjustment hex screw. This was a major problem!

First Prototype Manifold | Cross Company

First Prototype Manifold

Cross Company strives to solve customer’s problems, so we worked with the new vendor to redesign the manifold so the valve could mount in an offset position to clear the handlebar. This was harder than it sounds because of the reworking of all the internal porting and getting our manifold galleries to line up properly with the bottom o-ring porting. Our OEM is currently working on getting the new units beta-tested in the field and expects to implement this problem-solving solution into their production soon!

New pilot manifold | Cross Company

New Pilot Manifold

Our OEM trusted Cross Company to help them solve their current issues of very long lead times, inconsistent valve performance, and legacy product pricing issues. In return, they got a solution that has a short lead time, very good valve performance (with no more inconsistent behavior due to excessive pressures), and a 56% reduction in overall cost!

Contact Cross Company

Chris has a BS in Business - Marketing from the University of Alabama at Birmingham and is both a Certified Fluid Power Pneumatics Specialist & Certified Fluid Power Hydraulics Specialist with the International Fluid Power Society. He has been with Cross Company in various roles since December 1993, and currently works for Cross Company Motion Solutions as a Pneumatic Account Manager in Alabama, Mississippi, & the Florida Panhandle.

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