What You Need to Know to Ace the Statics Section of the Mechanical FE Exam

So, you've signed up for the Fundamentals of Engineering (FE) Mechanical test, and you are starting to think about studying - great! The FE is an important step in getting your professional engineering license, and for many schools, it is a requirement that you at least attempt the FE before graduating. Of course, you want to pass on the first try and avoid paying for the exam a second time! This post will share some of the tactics that I used when I studied for and passed the FE Mechanical exam.

The Blog Covers:

1. Background

2. Statics Sections

3. Study and Preparation Ideas

4. Resources for Exam Preparation

5. Test Day Tips

1. Background

Statics is the first of the "meaty" topics in the FE Mechanical exam and was likely one of your first real engineering classes. This is a good thing because statics has been fundamental to all your studies! However, this can be a bit daunting too since it has probably been a while since you took the class.

The exam specification from the National Council of Examiners for Engineering and Surveying (NCEES) shows us that the exam will have 9-14 statics questions¹. Given that the test is 110 questions in total, statics will likely be around 10% of the total material you will face on exam day. Personally, I think it feels like more than 10% once you include any statics involved in problems for other sections like Mechanics of Materials. Since many mechanical engineering classes build statics right into the subject matter, this will be a good section to score some quality points!

2. Statics Sections

NCEES says that the statics portion of the test is broken into the following subtopics:

A. Resultants of force systems

B. Concurrent force systems

C. Equilibrium of rigid bodies

D. Frames and trusses

E. Centroids and moments of inertia

F. Static friction

I thought that it was helpful to categorize my study questions as I was preparing. This kept me from over-studying one subtopic and neglecting another. If you happen to know that you are proficient with calculating moments of inertia or concurrent force systems, focus on the subtopics that are harder for you. The goal is to go into test day with an overall comfort with statics, not mastery of just a couple subtopics.

The other thing to keep in mind is that statics problems are generally among the more simple and straightforward problems on the test. The advantage to this is twofold. Firstly, it makes it easier to practice a wide variety of problems in less time. If you are confident going into the test, you will be able to quickly solve at least a few of the statics problems. This is important because it can free up time for you on the back end of the test when the topics are more specific and take a little longer to solve.

3. Study & Preparation Ideas

I used a few different ideas to keep me on task and organized when studying for my FE. Hopefully these can also help you!

The first piece of advice is to get familiar with the FE Handbook, which is available free from NCEES once you have an account. The handbook has all the information and equations you will need to solve FE problems. The book is going to be your best friend when studying and during the test. At the time of this writing, the statics section of the handbook is only seven pages long. You will want to know how to get to these pages quickly using the search pdf function, which you will have access to on test day. You will also want to practice identifying which category your practice problems fall into and navigating quickly to the right section. This will help you for any section of the FE, not just statics.

The statics section of the handbook has information to find areas and centroids, moments of inertia, and other geometrical properties for a variety of shapes. Some of this information can even be useful in other sections of the exam like Mechanics of Materials. You will also see information for solving systems with trusses, friction problems, and force resolution into x and y components. Most of these topics only have a handful of equations associated with them, which will make life easier for you under the pressure of the exam. Remember to identify which section in the handbook applies to your practice problems. On test day, you will know exactly where to look for information!

The second method that helped me study for the statics section was something that may or may not work for you. I like to see as many problems as possible before an exam, and I am confident in my arithmetic skills. With this in mind, I will sometimes practice problems until my equation only has one variable left. At this point, you know that it is all just algebra and arithmetic to solve for your answer. In order to save time and get more practice, I will often move on to the next problem at this point. Not everybody likes this method, but it is something that I have used judiciously in the past. Give it a try if you feel comfortable with your algebra and arithmetic skills!

The final piece of advice for studying is time management. I would recommend signing up for the FE well ahead of the test day if possible. This will put it on your schedule and force you to start thinking about the test. You will be more likely to be motivated for studying if you are registered. The other aspect of time management is how you handle time during the test. Timing yourself is a great way to simulate a little pressure like on test day. It also helps you see which problems you struggle with and which ones are easy - plus you can notice improvement over time. Not all your studying needs to be timed, but I like to mix in some timed problems. The final tip for time management is to be sure to set aside a fixed time to study in advance. It takes discipline, but studying 1-2 hours a week for two months will yield better results than 8 hours of study the day before the test.

4. Resources for Exam Preparation

The number one resource for preparing for the test is the FE Handbook. It is the one thing you will be guaranteed to see during the test! Again, I recommend becoming very familiar with the handbook layout and using it during all of your practice. For practice problems, NCEES sells a practice booklet, which can be useful and shared among a group of friends to make it more cost effective. School of PE offers many resources that can be useful for your preparation too. Overall, it is a good thing to gather up a pool of practice problems and resources from several different sources. Many universities also offer FE review sessions or tutoring, which can be a great way to get more one-on-one assistance.

5. Test Day Tips

So, you have studied hard and are headed to the testing center - time to put all your practice to use! When I took my exam, I did some "light" review beforehand. I looked over solutions to several problems that I had worked out but did not attempt any new ones. It is a long exam, so make sure to eat ahead of time and bring a snack for your mid-exam break. Try to stick to your normal routine and activities. It can also help to plan a fun activity for after the exam as extra motivation. You should be able to relax when you see the statics questions pop up on the exam - you know exactly where to find equations and are well prepared!

Prepare for your FE Mechanical exam with School of PE! We offer numerous course options like Live Online and OnDemand to best fit our students' busy schedules and learning preferences. Sign up today!

Reference

¹ https://ncees.org/wp-content/uploads/FE-Mechanical-CBT-specs.pdf

About the Author: Michael Wise

Michael Wise is an electrical engineer currently working in the power industry. He holds a master's degree in electrical engineering and a bachelor's degree in mechanical engineering.

Diesel Engine Components and Their Functional Applications

In general, engines convert heat energy into mechanical energy by exploiting gas onto the piston and crankshaft assembly. The amount of energy depends on the rotational speed of crank shafts as per specifications. An internal combustion engine (ICE) is more efficient than a steam engine because an ICE is simple to start and disengage. An ICE is widely used in the field of transportation.

Important components of internal combustion engines include:

1. Fuel system

2. Lubrication system

3. Air intake system

4. Exhaust system

5. Cooling system

6. Electrical system

1. Fuel System

In an engine, fuel reaches the cylinder bore through the following path:

Fuel tank -> Water separator -> Feed pump -> Filter -> Injection pump -> Injector nozzle -> Cylinder 

• The fuel tank is for storing fuel. Generally, it is made of sheet metal. Most fuel tanks have a fuel gauge to check the fuel level and a drain plug to drain fuel.
• The water separator is used for separating dirt and water from the fuel. 
• The feed pump is used to feed fuel to the filter and injection pump.
• The fuel system must pressurize the fuel to open the nozzle. The pressure required to inject fuel into the combustion chamber to offset the pressure of compression is typically 350 to 450 psi. This work is mainly done by the injection pump.
• The injector nozzle injects fuel into the combustion chamber. The injector nozzle atomizes fuel, which is the breaking up of fuel into small particles. The fuel must be atomized when it enters the combustion chamber. Atomization occurs at a pressure between 1,500 to 4,000 psi.

2. Lubrication System

Various purposes of lubrication include: 

• Reduces the wear and prevents seizure of rubbing surfaces
• Reduces the power needed to overcome frictional resistance
• Removes heat from the piston and other parts
• Separates piston rings and cylinders
• Removes foreign material from the engine

In this system, the engine parts are lubricated under pressure feed. The oil is stored in the oil sump, from where an oil pump takes the oil through a strainer and delivers it through a filter to the main gallery. From the main gallery, the oil flows to the main bearings. After lubricating the main bearings, some of the oil falls back to the sump, some is splashed to the cylinder walls, and the remaining oil goes through a hole to the crankpin. From the crankpin, the oil travels to the piston pin through a hole in the connecting rod web where it lubricates the piston rings. For lubricating camshaft and timing gears, the oil is led through the separate oil line from the oil gallery. The valve tappets are lubricated by connecting the main oil gallery to the tappet guide surfaces through drilled holes. Our FE mechanical exam review course thoroughly explains the fundamental concepts and functional applications of mechanical engineering equipment parts.

Oil Cooler

An oil cooler is used for cooling lubricating oil. Higher temperatures will reduce the viscosity of oil, which causes a harmful oil film to form between moving parts. To eliminate this, an engine oil cooler is used. 

3. Intake System

Air flows into the cylinder bore through the following path:

Air cleaner -> Turbo charger -> Intake manifold -> Inlet port -> Inlet valve -> Cylinder bore

• The air cleaner is a filter that prevents dust from entering the cylinder bore. Filters generally have pores on the surface, which are measured by microns. The lowest micron value typically has better filtration. A filter set contains outer and safety filters in heavy diesel engines for better filtration.
• The tuber charger is a very important part in an engine that compresses air from the air filter. Turbo chargers have two impellers fixed on the same shaft. These impellers are driven by exhaust air. Generally, the air sucked in by the air filter is compressed before entering the cylinder bore, which results in high efficiency. The shaft will rotate at the speed of approximately 100,000 rpm to result in a longer engine life.
• The intake manifold is a pipe that transports air from the turbo charger to the inlet port.
• The inlet valve is a valve that allows air into the cylinder bore. The opening and closing of the valve is controlled by a camshaft.

Ready to test your knowledge? Explore our practice exams now!

4. Exhaust System

Exhaust gases flow through the following path in an engine:

Cylinder bore -> Exhaust valve -> Exhaust port -> Exhaust manifold -> Turbocharger -> Muffler

• To reduce engine noise, the exhaust is passed through the muffler. The exhaust gases have a higher pressure than atmosphere; if these gases were to be released directly to the atmosphere, a loud, unpleasant noise would sound, similar to the sound of firing a gun. The muffler is used to cool the exhaust gases.

5. Cooling System

There are many purposes of cooling an engine, including: 

1. To maintain an optimal temperature for efficient work in all conditions.
2. To avoid excess heat and to protect engine components including cylinders, cylinder head, pistons, and valves.
3. To maintain the lubricating property of the oil. 

There are two types of cooling:

1. Air cooling 
2. Water cooling

Every cylinder in an engine is surrounded by water jackets. The water in the jackets absorb heat from the cylinders. The heated water conducted through the radiator helps cool the water.

There are three types of water cooling methods:

1. Direct or non-direct method 
2. Thermosiphon method
3. Forced circulation method

Mechanical engineers preparing for the FE exam are strongly encouraged to review heating and cooling systems prior to taking the FE Mechanical exam.

6. Electrical System

The electrical system of an engine is comprised of the following parts: 

1. Starter Motor
2. Alternator
3. Battery 

The starter motor is used for rotating the flywheel. A starter motor receives its power supply from the battery. The pinion of the starter motor engages with the teeth of a flywheel ring and rotates, which then rotates the crankshaft. This rotation of crankshaft leads to the movement of pistons in the cylinders. The piston will suck air and fuel into the combustion chamber, which causes the engine to start. After reaching a specific rpm, the starter motor withdraws its pinion from the flywheel.

The alternator is fixed on the engine and includes a pulley. The belt is used to drive the shaft of the alternator. The main job of the alternator is to charge the batteries.

In general, two batteries, each with a 12 volt capacity, are used.

Introduction to Basics of Boiler Components for Mechanical Engineers

The most important components of boilers include fuel oil systems, super heaters, and ash removal systems. As a mechanical engineer, it is extremely critical to understand the various components of boilers. Heat transfer is an important topic for undergraduate mechanical engineers preparing to take the FE Mechanical exam to understand. Heat transfer is thoroughly reviewed in our FE Mechanical exam review course. 

Table of Contents

1. Fuel Oil System

2. Super Heaters

3. Ash Removal

4. Common Types of Boilers for Engineering Applications

1. Fuel Oil System

Oil-fired boilers may use a light grade oil, typically diesel, or a heavier grade residual oil that is often referred to as "Bunker Fuel." Light oils have a low viscosity and do not require pre-heating. They are pumped from the storage tank to the burner, which is equipped with an atomizing tip that sprays the oil into the furnace in the form of a fine mist. The mist mixes very rapidly with the combustion air, ensuring efficient and clean furnace operation. Heavy residual fuel oils are viscous and require pre-heating for proper atomization. The most commonly used residual fuels are typically more viscous. The temperature required to achieve optimal atomization may differ between fuels.

2. Super Heaters

Steam leaving the boiler is routed through the super heater element, which is located in a high-temperature zone of the furnace. The moisture quickly evaporates because the steam is no longer in contact with the water in the drum. The actual difference between the saturation temperature and the actual steam temperature is called the degree of superheat. Although superheating does add additional energy to the steam, the primary objective is to provide a margin of safety by ensuring that the steam does not immediately begin to condense prior to giving up its superheat energy component. Super heaters are commonly used in water tube boilers. The nature of the process determines whether a super heater is required; a super heater is not generally used unless there is a specific need.

3. Ash Removal 

Environmental legislation in most jurisdictions imposes strict constraints on particulate emissions. Therefore, removing entrained fly ash is usually a mandatory requirement on solid-fuel boilers. For large boilers, electrostatic precipitators, bag houses, and scrubbers are widely used. One of the most common methods employed on small to medium sized boilers is the multi-cyclone grit arrester; it has low capital costs and a degree of efficiency that will satisfy all but the most stringent requirements. Understanding boiler components and heat transfer mechanisms is critical for the FE Mechanical exam. Our FE Mechanical exam review course thoroughly covers the topics of heat exchangers, boiling, and condensation. 

4. Common Types of Boilers for Engineering Applications 

(i) Fire tube boilers: 

Fire tube boilers have the advantage of relatively low capital and operating costs. These types of boilers are predominantly used in industries and processes that have modest steam demands at low to medium pressure. Physical size constraints impose limits on operating pressure and because of their large mass, fire tube boilers are not well suited to large, rapid changes in steam loads. 

(ii) Water Tube Boilers 

The water circulation through the tubes of a water tube boiler follows a defined path. This process ensures that a relatively small quantity of water will be rapidly distributed by heat, which results in an efficient operation. Water tube boilers can be brought up to working pressure much more quickly than fire tube equivalents.