MaxxForce® Engine Plant Tour
Navistar Diesel of Alabama
I was pleasantly surprised when I received an invitation to visit the Navistar Engine Plant in Huntsville, Alabama. After responding “Yes” (of course) we made the necessary reservations and departed for Huntsville. From Myrtle Beach we headed to the I-20 toward Birmingham. We stopped short of the Alabama border on our first day and on the next day we motored along to Anniston and headed on in to Huntsville on SR431. We arrived in the early afternoon. After setting up we took it easy for the rest of the day and enjoyed a nice walk around the Monte Sano State Campground with Miss Roxy leading the way.
From our 1,600 foot high campsite on top of Monte Sano Mountain, the 20 mile trip out to the Navistar Diesel of Alabama engine plant took a little more than a half an hour. Traffic in Huntsville is like anywhere else in the morning, bumper to bumper. Going through town there is construction underway to widen the road, which passes by Huntsville Hospital. A glance outside my passenger widow showed an automated shuttle train on an elevated rail going from one building to the next. Rolling along on the I-565 you pass the US Space and Rocket Center, which hosts Space Camp. Passing the Davidson Center for Space Exploration, where you can see one of the 15 Saturn V rockets, you observe the large components of the rocket through the windows. Further down the road you will find the NASA Marshall Space Flight Center and the Redstone Arsenal. It was in these facilities that Dr. Werner Von Braun developed the Saturn V rocket that took the United States to the moon. Huntsville continues today to attract high tech people to its industries.
Taking Exit 7, and continuing in on Glen Heath Blvd, the Navistar engine plants are located adjacent to the Huntsville-Madison County Airport. With a left turn on James Record Row SW you can see that Navistar has 2 large plants within a mile of one another. Easily identified by the big blue Navistar signs on the side of the buildings, the plants are named appropriately the Big Bore Plant and the Vee Plant.
The 300,000 sq foot “Big Bore” plant opened in 2008 and produces the MaxxForce® 11, 13 & 15 engines. The facility yields a maximum of 308 engines per day, with a capacity of 60,000 engines per year with two shift operations. The line stretches 1,595 ft in length and has 10 automated stations and 7 leak test stations that use 50 error proofing tools, as well as 12 cameras. The facility also has a dynamometer where engines are randomly pulled and run up to operating temperature.
The 700,000 sq ft “Vee Engine” plant opened in 2002 and manufactures the MaxxForce 5, 7, 9, DT & 10. The plant can concurrently build any model engine it produces on its ½ mile long assembly line in any sequence. Unlike Big Bore, the Vee plant is equipped to machine crankcases, crankshafts, camshafts and cylinder heads using state of the art robotic machines. The production of the major sub-assemblies is mostly accomplished by the use of robotics. From start to finish it could take approximately 24 hours to build a MaxxForce 7 engine.
Both campuses employ approximately 300 people in total. Together both facilities have produced nearly 800,000 engines. Huntsville supplies engines to Navistar plants in Springfield, Ohio; Garland, Texas; and Tulsa, Oklahoma including the Blue Diamond facility in Escobedo, Mexico, a joint venture operated by International and Ford. In addition, Huntsville supplies engines to Monaco RV in Coburg, Oregon, Workhorse in Union City, Indiana, and Tiffin Motorcoach in Red Bay, Alabama.
The technology to produce MaxxForce engines comes from the Navistar Research and Development Center in Melrose Park, Illinois, just outside of Chicago. Navistar has invested about $90 million in the 80-acre development and testing facility. According to recent press, Navistar stated that 3,000 permanent jobs will be filled over the next several years. Located on the campus are state-of-the-art testing facilities that offer the use of wind tunnels, including 50 dynamometers that are used to develop and test all manner of products for Navistar. The cumulative engineering that is developed at Melrose Park and with its other global partners lays the foundation for the manufacturing of all MaxxForce clean diesel engines.
In 2009 Ford announced they would be building their own engine in Mexico and as such the demand to build engines in Huntsville for Ford was drastically reduced. During this time, Navistar was faced with the fact that there were 50 employees too many. Since the demand was down and there were excess employees, Navistar had to figure out what to do with these people. Faced with this reality and knowing that business would improve, they did not want to loose any of the people with key skill sets that took such a long time to develop. For a brief period of time, those 50 people were paid their normal weekly salary. However, they were not building engines. The engine group leaders assigned those 50 people into the Community where they worked for 4 months until they were recalled. The City of Huntsville was very pleased to get the help from the Navistar employees. The people that benefited from their work appreciated their efforts.
L to R. The engine is etched with a laser ID tag. The rod caps are also etched and identified by number 1 & 2 through 7. Each cap is unique to its space by a hydraulic fracturing process called “Sure Lock Technology.” When torqued, the facets in the cap match the engine block and form a solid bond as strong as if it were never separated.
I could not help but notice the workers on the line; although attentive to their work, they had time to offer a smile and a wave on occasion. One gets a sense of pride from the people that are employed at the plant and it’s easy to see that they enjoy working there. When the employees enter the building they are greeted by the current safety status of the plant, which is displayed on placards. As of March 2011 there were 4,000,000 man hours of operation without any loss of time. Safety in the plant is their number one concern. In the event of any situation that may have caused an injury to an employee, the incident is reviewed by all and a remedy is discussed and applied so it does not happen again. The employees work a 40 hour week; four 10 hour days. In the last hiring campaign, over 1,500 people applied for 60 jobs. Another round of hiring may have already occurred by the time you read this, as 60 more people are expected to fill job vacancies in both plants.
Beginning our tour of the plant, Jason Ball, welcomed us and we were given a briefing about the layout of the facility and how the engines moved through the phases of production. The Navistar “Big Bore” diesel plant produces the largest MaxxForce engines, the 11, 13 and 15. Any of these engines we are told could be adapted for RV use. As you walk along, one notices the absence of loud noises in this building. I recall we spoke in normal voices and didn’t have any problem communicating. Although there were quite a few machines and robotics on the floor, the sound levels were quite low.
As we made our way through the plant, we passed many completed engines that were waiting to be shipped out. On this day we were told that the majority of the engines that are shipping are for commercial use by the International truck manufacturing facilities across the country. Looking over a sample of the engines, I noticed that many had flywheels that are tasked for use with standard transmission applications. Looking further, I saw a few engines with what I would call a ring gear for automatic transmission use, which may be typically seen on RVs or other commercial vehicles. In one brief stop, Jason made a point of showing us that the valve covers were completely free from operating hardware. Jason said, “This reduces the time that may is needed to check anything under the valve cover since no other equipment requires dismantling.”
As we arrived at the engine block processing area, there were graphic displays and an engine block which is used to demonstrate the construction details of the bottom of the engine. Close inspection shows a 5 character laser etched serial number and a data matrix symbol that is assigned to each engine. The data matrix symbol looks like a 1” x 1” square with random dots. In this display, the engine’s serial number is carried through to each connecting rod cap. However, each is preceded by its numeric position in the engine. As the engine is built, the numbers and squares are scanned by the various electronic monitors and sensors to verify correct installation and record data for that engine.
This memory device resides in the engine cradle and it accompanies the engine throughout its production. Every scanned part, torque and inspection is recorded to this chip and the data is retained as a permanent record and keyed on the engine serial number.
The MaxxForce 11 and 13 blocks feature “Smart Engineering” called “Dry Decking” where coolant and pressurized oil is not allowed to flow from the block to the head via the head gasket, thereby eliminating the possibility that coolant will mix with oil. Oil and coolant are directed to the head via the water pump housing connections on the face of the engine. This eliminates the possibility that the head gasket will ever fail. Cross coolant flow technology in the block assures even cooling throughout engine which reduces cylindrical distortion and assures long life.
The engine block is the first Class 8 engine in the industry that is made from compacted graphite iron (CGI). The material of the block contributes to very low noise, vibration and harshness (NVH) which increases owner comfort, provides light weight, and dissipates sound wave transmissions. In the design, each main bearing cap has a unique signature that can only be matched to its original position. The main bearing caps are line bored and hydraulically fractured. In the pictures you can see that the thousands of facets make it impossible to mismatch bearing caps. The unique feature of this technology assures precision alignment of the main bearing caps, which assures better crankshaft alignment over the million plus miles that this engine will be in service.
Engine crankshafts arrive from global suppliers and are ready to be installed in the engine block. Crankshafts are transitioned to the engine block by a special lift gig. The fitting of the crankshaft is done in one precision movement and is gently lowered onto a set of upper main bearings.
Each engine block begins its assembly process by being hoisted approximately 4 feet off the floor via a unique lift. At height, a pin is pulled and the engine is allowed to spin via gravity vertically 180° degrees. With the bottom of the engine facing up, it is walked over to an engine stand on the line and mated to 4 holding pegs. The engine stand is integrated onto a horizontal mover, which propels the engine forward at a slow but deliberate pace. The stand holds an electronic asset tag that records every single process while the engine is moving on the line. The tag will record component installation, part verification, alignments, torques and other data that will become part of the permanent record for that engine.
As the engine moves down the line it arrives at the crankshaft installation station. The crankshafts come pre-machined and ready for installation. The main bearings on this engine come in 2 pieces, an upper and a lower bearing. The upper bearing facing toward the block has 2 oil passage holes where the bottom bearing in the cap does not. A person inserts the bearings under observation by a camera and if the camera does not see the 2 holes the operator is notified by a signaling device that the install is not correct. The crankshaft is then fitted by robot since it always lands the piece right where it’s supposed to go. The next process will see where the caps and bearing are installed over the journals and 2 large bolts are dropped through the cap holes and started. Moving forward, the 14 main bearing caps bolts are torqued by a twin socketed robot arm.
Robotics play an essential role in the manufacturing process by scanning, recording and applying the torque to the engine components. In this photo a robot is preparing to torque the main bearing caps. Prior to this station, a worker placed numbered caps and bearings and inserted the bolts. Upper and lower main bearings are different and are scanned by a computer to assure correct positioning and assembly.
At the next station pistons, rings, wrist pins connecting rods, bearings and caps are installed. Jason demonstrated that the 11 uses an aluminum piston whereas the 13 uses a steel piston. Although both engines are approximately the same size and weight, the pistons define the application of the engines. The 11 offers less rotational mass and as such yields improved fuel economy. The 13 on the other hand is provided with more mass which provides increased torque and horsepower. Proprietary in nature, the design of the crown of the piston is called a combustion bowl. By shaping the charge and applying higher fuel pressures, the fuel is broken up into fine particles that are more easily burned resulting in more power and less soot.
L to R. One can see the offset difference between the MF15 and the other big bore piston rods. The offset rods use “Sure Lock” technology. Details of the shaped bowl in the crown of the piston. MF15 rod assembly and wrist pins. Big Bore offset rod, cap and piston.
–> For greater detail .. “Click” on the small pictures <--
MaxxForce® Engine Plant Tour – Part 2