Super Air Nozzles Extend Maintenance Schedule in a Chocolate Factory

The process of making cocoa powder and chocolate products is fascinating to say the least.  The video above shows the process at the Hershey factory in a throwback “How Its Made” video from the 70’s. (I think; based on the hairstyles.  Also based on the video description, but mostly based on the hairstyles.)  It’s interesting to see the process and the mechanical aptitude it took to create the machines, especially with the weights and measures.  The level of complexity and number of steps involved can make you wonder how we ever figured it all out, but thankfully we did!

Current cocoa production follows the same basic process through harvesting, roasting, extracting cocoa butter, and grinding of cocoa cakes into powder.  And, like any manufacturing process, there are sure to be applications which demand unique solutions.  This is where a recent application took place for an EXAIR end user.

20160530_092938
The cooling carriage for the cocoa powder

Not shown in the video above is a cooling process for the cocoa powder.  During the cooling process the powder is transferred through a carriage system resembling a radiator without the fins.  Inside the carriage system cocoa powder can accumulate in the 180° bends, and the build-up over time can stop material flow.  So, these bends are serviced as part of a regular preventative maintenance program.

20160530_093713
Cocoa build-up in the curves of the carriage

The end user was looking for a way to extend the service interval length, hoping to find a solution to target the build-up areas in the 180° bends.  The current setup requires manual cleaning every 15 days of operation.  Modification of the existing setup is possible, provided it increases the time between maintenance procedures.

20160530_093039
The service procedure

The solution we devised is a series of 316 stainless steel Super Air Nozzles, fed into the curves of the cooling carriage to prevent accumulation of the cocoa powder.  The solution agitates any accumulating cocoa, removing the build-up and greatly extending the time between service intervals.

This solution can be implemented in one of two ways; either through periodic entry of the nozzles into the cooling carriage (a somewhat difficult solution to implement), or through permanent installation with guarding in place to protect the nozzles (even powders can deteriorate a material with direct contact over time).  A (very) crude representation of the permanent installation is shown below.

Cocoa curves
A quick sketch of the possible permanent solution

To install the nozzles into the curves of the cooling carriage, holes must be drilled into the curves.  Sealed bulkhead fittings can be installed into the holes, and the necessary compressed air lines can be fed through the sealed bulkhead fittings.  This will allow installation of the air nozzles in the needed locations.

The final detail left to be sorted in this application was the exact model Super Air Nozzle to be used.  The force requirement to dislodge the cocoa is highly specific and ultimately unknown, so we focused on a solution with what we deemed adequate force at an 80 PSIG operating pressure.  We chose a series of 1101SS Super Air Nozzles, remembering we can always reduce force and compressed air consumption through pressure regulation if needed.

We were happy to help implement a solution to provide the needed results with the most efficient use of compressed air.  After all, that’s what we do at EXAIR.  We help our customers find the most suitable, most efficient solutions for their applications.

If you have an application and would like to discuss a compressed air-based solution, contact an EXAIR Application Engineer.

Lee Evans
Application Engineer
LeeEvans@EXAIR.com

Safety, Efficiency, and Production Improvements

Last week, I received an email from a satisfied customer, after he had already purchased our product.  Come to find out this customer had not spoken to an application engineer during the planning stage to make their purchase. With our excellent resources listed at EXAIR.com, the customer was able to fulfill his application without even speaking to us. After his initial email of thanks, he also shared with me some details of his application that I want to share with you today.

The customer works as a machinist at a large aircraft part manufacturer. The parts require a very tight tolerance. A sample of each part needed to be gauged and measured in an automatic thread gauging machine or a coordinate-measuring machine (CMM). Their machining process required a water based flood coolant, so each part would be coated in water based coolant and chips, which needed to be remove before gauging. Before visiting EXAIR’s site, the company used a variety of homemade and commercial blow offs, as safety air gun tips. Here is a photo of (20) of the (25) nozzles the customer was using.

Aircraft manufacturer's obsolete nozzles

As you can see, the nozzles vary in design purpose, flow and safety. Most of the nozzles feature a cross drilled hole or a secondary escape path, but not all of the nozzles do. Any nozzle without a secondary relief port violates OSHA standard CFR 1910.242(b), so replacing some of the nozzles increased the safety in the plant. Secondly, these nozzles are wasteful in their use of compressed air because some were designed as liquid nozzles and have large exit holes. A hole that is 1/8″ in diameter at the nozzle outlet can consume up to 21.4 SCFM of compressed air at 80 PSIG. For comparison, the model 1103 Mini Super Air Nozzle with a 1/8″ NPT inlet will flow 10 SCFM at 80 PSIG, which would be a 53% compressed air savings. In 24 running hours, the 1103 nozzle will save 16,416 Standard Cubic Feet, which the plant spent $4.10 for a standard industrial compressor to produce (The standard for compressed air cost is $0.25 per 1,000 SCF). Replacing just one 1/8″ drilled hole with 1103 Mini Super Air Nozzle saves the aircraft company $1,026 over 250 working days running 24 hours a day.

Neither of these were the real reason that the customer emailed to thank us though. He was actually an office employee just entering the work force.  Starting in June until after the company finally acquiesced to his request to buy a better, quieter nozzle near the end of July, he had left work needing an aspirin to relieve the headache he acquired due to the noise from these other nozzles. The nozzles the machining center had been using would create noise levels between 88-100 dBA at 80 PSIG of inlet pressure. For reference OSHA mandates that employees are required to wear hearing protection, if they are exposed to noise levels over 90 dBA over an 8 hour work day.  The employees doing the machining wear hearing protection, but the employees in the office were still exposed and affected by the noise level.  This is just one anecdotal example, but everyday more and more research shows that noise exposure has a negative effect on our health and productivity in the workplace.  If you are interested in more information here are some links to a number of studies/research – please read this, here or this.

Anyway, that’s enough of my soapbox. The company purchased 25 of EXAIR’s 1103 Mini Super Air Nozzles and utilizing the same guns they were currently using saw between a 10-15 dBA decrease in noise levels near the work stations. Here is a photo of one of their setups with the model 1103 installed on one of their current air guns.

Nozzle Replacement
The 1103 Super Air Nozzle is an engineered solution to replace a plethora of commercial nozzles. It was a simple and cost effective retrofit which increased the comfort of employees.

 

We know that every time they squeeze that air gun trigger they will be using less compressed air than before, and we know they are now in compliance with OSHA. But the best benefit for EXAIR is we know that the engineer took the time to email us to thank us for taking away his headache everyday.  That’s enough for me.

Dave Woerner
Application Engineer
DaveWoerner@EXAIR.com
@EXAIR_DW