From humble beginnings in Doncaster, England in the early 1970s and £100.00 to invest we have developed into a worldwide company with manufacturing bases not only in the US but also in the UK, India, Brazil and China. Two visionaries, Michael Crawley and Brian Snowdon, with a same dream but complimentary talents saw an opportunity in the market, joined forces and Macawber Engineering Limited in the UK was born.by
August 28, 2017
Come and see our dense-phase, low-velocity pneumatic conveying system in operation at the 2017 Midwest Powder Show at the Greater Columbus Convention Center in Columbus, Ohio, September 28-29. We will be in booth 209, and we look forward to demonstrating the simplicity of our equipment and technology as well as explaining the principles behind conveying powdery materials with no or minimal material degradation or pipe wear while also creating cost savings through reduced energy usage. Whatever your conveying requirements, our team has the experience to discuss how we can improve your process. See you in Ohio!by
Macawber Engineering, Inc. will be featured in Globalspec’s June issue of “Material Handling & Supply Chain Technology”. Globalspec, also known as Engineering360, is “the world’s largest online destination for engineers, delivering the single source for critical engineering content, information, insight, tools and community for engineers and technical professionals across multiple industries and disciplines”. Engineering360’s website contains news, products, suppliers and much more. You can check out our profile on Engineering360 and subscribe to their newsletters by clicking on the links below.by
Denseveyor installed below a feed hopper
[P3674] Macawber Group Installation Case Study:
Sodium Bicarbonate Conveying system, Northwich, UK.
The dense phase pneumatic conveying system was supplied to convey 14 t/h of sodium bicarbonate over a distance of 26 ft. horizontal and 98 ft. vertical. The system is an 8 cubic feet Denseveyor® with a 5” pipe line and is located under a feed hopper with start and stop controlled in automatic by the feed hopper and silo reception level probes. The system was first installed in November 1996. In July 2014 after 17 years of continuous daily operation it was upgraded with a touch screen operator interface, new filling Dome Valve and air manifold. The vessel and pipe line remain originals and are in very good condition expected to offer many more years of service. The pipe line, bends, and vessel are made from stainless steel 304 with all external surfaces coated in a corrosive resistant clear lacquer.
Mactenn Systems, our sister company in the UK, has today announced that Lysair Air Solutions has been appointed as the exclusive representative of Mactenn in Belgium, the Netherlands, and Luxembourg. The company specializes in projects aimed at environmental conservation and is well known for its strength and know-how in providing high quality solutions to dust handling needs from equipment supply to complete installations. By adding our dense-phase pneumatic conveying line to its offering, it is able to add value and scope to its local customers being able to meet a wider range of requirements. The co-operation will strengthen Macawber Group’s international network and adds to our ability to offer installation services to our European customers.by
Dense Phase Pneumatic Transporters
1. Dense phase pneumatic conveying pressure vessels were introduced to the U.S. markets in the early 1960’s. Pressure vessels were used because the pressures required for dense phase conveying normally exceeded 15 psig – the limit at that time for rotary airlock valves which were used almost exclusively by manufacturers of positive pressure dilute phase systems. In order to accommodate the higher pressures necessary for dense phase conveying systems, ASME coded vessels became mandatory.by
What are the reasons for blocked conveying lines?
All pneumatic conveying systems block sometimes. Clearing a pipeline means downtime, loss of production, and can be a maintenance headache. So ensuring your system runs as smoothly as possible day after day is critical. Here at Macawber we have been designing pneumatic conveying systems for years, using our knowledge and experience to design systems that aim to provide the most reliable and maintenance free systems possible. We do not like blockages or any other maintenance issues any more than you do. But if they do happen, understanding where to look to minimize downtime is essential.by
Why is Electric Arc Furnace (EAF) Dust so difficult to convey?
The EAF dust generated in a combustion process by electric arc furnaces employed in steelmaking is a hazardous material containing many heavy metals such as lead, cadmium, zinc, etc. These materials are not only hazardous requiring safe and reliable methods of conveying and disposal but they are also highly abrasive and poorly flowing. Furthermore EAF dust can have high moisture content. As a result EAF dust is a challenge to convey and special considerations must be applied to the way the material is fed as well as conveyed. The best way to convey EAF dust is using dense-phase pneumatic conveying which has the ability to convey EAF dust reliably with an added benefit of minimizing pipe wear.by
We often get questions from our clients that come in to our service department. Here is a common Q & AQ. When troubleshooting, should I return to the factory settings? A. Yes. Every time. When our service technician has completed commissioning your system, you will be sent a record of the machine settings that provided for the optimum conveying conditions. Return to these settings. If you cannot locate the factory settings, please call us at 1.800.433.2213 (ext. 120) and ask for Mike DeLand. Or email him at: email@example.com We have these on file. If the system is still not functioning correctly, we will be able to assist you with your needs. The problem could be a variety of causes, for instance, a faulty component, a change in the material conditions or air supply, or other minor issue. The advice you receive over the phone is free, so please do not hesitate to give us a call. Read the full article… by
We have successfully tested another 250 mm Stainless Steel 3-way T-Type Diverter Valve to be used for conveying fish food. The Diverter Valve is designed to be used in dense-phase pneumatic conveying applications for handling fragile materials minimizing material breakage. The Diverter Valve is also available in the UK via our sister company, Mactenn.
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One of the notable features of our pneumatic conveying systems is their ability to handle hot materials. We first encountered hot material applications in the foundry industry. A common application is the handling of hot knock-out sand (the remains of the sand mold after the hot metal has been poured and the casting made) which could reach temperatures of 700-800 degrees F.by
Macawber Engineering Inc. has stayed true to it’s core for over 40 years. While other companies have been distracted by diversification and/or been taken over by larger companies, Macawber has stayed on the course for becoming an expert in everything related to low velocity, dense-phase pneumatic conveying, frequently called in to deal with difficult to handle materials and to solve unique customer requirements. Our reputation is attributed to our high standards in everything that we do from paying detailed attention to our customers’ needs to reliable and efficient designs, high quality products and customer service. We truly know what it takes and take great pride in it.by
We are pleased to announce a publication in the May issue of Powder and Bulk Engineering Magazine. The article written by our John Bell and titled “Pneumatically conveying fragile materials without particle degradation” focuses on discussing extensively the concept of conveying fragile materials and how to design an efficient, reliable and cost effective conveying system that minimises material degradation. Macawber has excelled in dense-phase pneumatic conveying for over 40 years specializing in difficult to handle materials such as pet food, peanuts, sugar, fish food, seeds, raisins, corn and others. Below is a link to John’s article:by
Dense phase pneumatic conveying is best described as using the lowest attainable material velocities to ensure the majority of material remains below the saltation level. It is a simple, efficient, cost-effective and safe mode of transport particularly beneficial for handling difficult to convey materials.by
Aerated Bulk Density is the ratio of material mass to volume when the material has been aerated. Note that some materials do not aerate. It is often necessary to aerate the material within the feed hopper to ensure that it enters the vessel and to aid conveying. Since the conveying rate is determined by the volume of material transferred within a particular time, knowledge of the aerated bulk density is vital to enable us to correctly size a system.by
The Macawber Macpump T150, a single system, but with two vessels. As one is conveying the other is filling and preparing to convey. The pneumatic conveying distance is 2955ft horizontal and 65ft vertical conveying over 100t/h of crushed limestone. The convey line starts at 12” and finishes at 14”. This was a challenging application due mainly to the limestone material being out of specification relative to the initial sample upon which the system was designed. However, with a few small modifications and careful optimizing the system achieved all the customer’s specifications and is now working 24 hours per day 7 days a week at a power station. Batch size and sequence control is by two sets of load cells with system control selectable either from the central control room via Ethernet communication protocols or at the local panel.by
First of all decide what kind of pneumatic conveying regime is required – dilute phase or dense phase. Dilute phase relies on a high air flow to maintain the material particles in a suspended condition. With chunky material the velocity to achieve complete suspension is extraordinary high and not very practical. So dense phase conveying, which does not rely on a high velocity for conveying is a better choice.
Dense phase systems operate at high pressure – anywhere from 20 to 50 psig depending on distance and other factors. This requires the use of a pressure vessel to introduce the material into the conveying line. With lumpy sticky material, the choice of vessel type is critical. These kinds of material tend to bridge easily in silos and hoppers – the same goes for pressure vessels. So to avoid bridging or jamming in the vessel discharge a small compact vessel with steep sides and a large transition between the vessel discharge and pipe line is essential.by
Two Macawber Fly Ash Systems were supplied to convey 30t/h each over a distance of up to 1,265ft horizontal and 121ft vertical. The ash systems use 40 cu.ft. vessels with a 6” pipe line. Both conveying systems are located under a feed hopper with start and stop controlled in automatic by the feed hopper and silo reception level probes. The Fly Ash systems are working very reliably with no line blockages and exceed the customer’s expectation regarding transfer rate and performance. These particular Macawber systems incorporated multiple manifold settings allowing the transfer of a range of Fly Ash products over various distances. The final convey air requirement on the longest route was 760scfm compared to the proposed 988scfm resulting in a saving both in cost and air used from the compressed air system. One particular problem was a very low control air pressure resulting in a compromised sealing of the Dome filling valve inflatable seal. This was overcome by installing a pressure doubler and small air reservoir to provide more than sufficient instrument air pressure and excellent sealing.by
The Denseveyor is a low velocity dense-phase pneumatic conveying system using here a single pressure vessel to cyclically transfer 10T/hour Malted Barley for 280 ft as it is made available by gravity feed to the machine. The Denseveyor is filled by gravity through the special Dome® Valve and when the vessel is choke filled the valve closes through the material and seals closed to a pressure differential of 7 barg. The conveying air is applied to the pressure vessel in a special controlled method that allows the material to pass down the pipeline at a low velocity reducing material degradation.
Three Macawber dense-phase pneumatic conveying systems were supplied to convey bed ash between 5t/h for the two smaller conveying systems and 56t/h for the larger system 3. Material transfer distances are between 158ft and 230ft. The ash systems use 2 x 4 cu.ft. vessels with 4” pipe lines and system 3 uses an 30 cu.ft. vessel on a 10” pipe line. All dense-phase systems are located under feed hoppers with start and stop controlled in automatic by the feed hopper and silo reception level probes to maintain empty feed hoppers and full reception silos. System 1 is used on the Economizer line with a water cooled top plate and dome filling component to withstand the high temperatures. System 2 and 3 are standard in that no additional equipment is required to handle high temperature up to 390°F material temperature. Other Ashveyor equipment supplied were switch type diverter valves, isolation high temperature knife gate valves, wear resistant bends and end diverters placed on top of the reception silos. System 3 conveyed the ash material directly in to the fluid bed of the boiler.by
Three dense-phase, low velocity pneumatic conveying systems were supplied to convey coal dust between 1.5t/h and 2.7t/h over a distance of 525ft horizontal and 30ft vertical. The systems were 2 x 3ft3 and a single 8 ft3 vessel all with a 3” convey pipe line. All pneumatic conveyors are located under a feed hopper with start and stop controlled automatically by the feed hopper and silo reception level probes. The material handling systems are working very reliably with no line blockages and exceed the customer’s expectation regarding transfer rate giving 2.9t/h for the smaller systems and 5.9t/h for the large system 1. The pipe line conveying pressure was between 8psi and 12.5psi. Convey air requirement was substantially less than that proposed at 88scfm and 180scfm. The proposed air requirement was 176scfm and 278scfm. The systems are pneumatic only to the ATEX equivalent of Eexd Class II Division 2. The customer elected to control the systems through their own high level PLC and DCS systems.by
The low velocity dense-phase pneumatic conveying system supplied conveys in 90t/h of mixed mortar over a distance of 360ft horizontal and 115ft vertical. The system uses a 52 cu.ft. vessel with a 8” pipe line. The system is located under a mixer which in turn is fed by multiple product feed hoppers. The starting and stopping sequence of the system is controlled automatically from a central control room via an Ethernet connection. The pneumatic conveyors are working very reliably and exceed the customer’s expectations regarding rate transferring over 130t/h. The system incorporated multiple manifold settings allowing the transfer of a wide range of bulk materials and sizes. The system set-up is done automatically simply by selecting the material recipe. Further options have been added since the initial start-up including a four way diverter valve and the addition of more reception silos and conveying lines. The end user is extremely satisfied with the system and the flexibility it offers considering the hundreds of different mixes that need to be conveyed.by
Two dense-phase pneumatic conveying systems were supplied to handle 35 tons per hour of Fish Food Pellets over a distance of 265 feet horizontal and 90 feet vertical. The systems were 30 cubic foot vessels with a 10 inch pipe line. Both systems were located under a feed hopper with start and stop controlled in automatic mode by the feed hopper and silo reception level probes.by