One of the most important valves used on a ship is the gate valve. Gate valves are typically made out of cast iron, cast carbon steel, ductile iron, gunmetal, stainless steel, alloy steels, and forged steels. Main gate valve parts include the spindle wheel, spindle rod, bonnet, valve disc, and bore or body. The opening of a gate valve will allow for only a full flow of liquid in one direction. There are valves that offer more functionality in the amount of liquid permitted to pass and in what direction, but for a simple and reliable open and close ship valve, the gate valve is perfect.

The spindle wheel is used to turn the spindle rod which in turn opens the gate in one of two ways depending on the type of stem installed. A Rising Stem Type which has a threaded stem that when operated, the stem rises above the actuator and the valve attached to the stem, opens. And a Non Rising Stem Type in which the stem valve itself is internally threaded and connected to the stem, so as to open and close without raising the stem above the actuator.

Important things to watch out for when owning and operating a gate valve is signs of leakage. The metal surfaces that come in contact with the flow of fluids can undergo wear and tear leading to leaking of the valve. Gland packing is used in the gate valve to stop such leakage around the spindle but this too can get damaged over time and should be regularly checked and reapplied periodically.  

Gate valves are suitable for most fluid transfer and can also be used with pipelines carrying steam, oil, air, and gas. Three main gaskets are used to ensure an airtight lock and a gate valve’s simple design makes it ideal when shopping in the market for a valve with a long life cycle.

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find the ship gate valve and spindle wheel parts you need, new or obsolete. For a quick and competitive quote, email us at or call us at +1-919-348-4040.

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In aviation, a stall is an aerodynamic condition in which an aircraft exceeds its critical angle of attack, and can no longer produce the required lift to maintain normal flight. While they use the same word, a flight stall is drastically different from an engine stall, which aircraft, as well as automobiles, can experience. An engine stall is a mechanical failure, while a flight stall is an aerodynamic failure and loss of lift.

The most critical component of a stall is a wing’s angle of attack, which is measured by the angle between the chord line (the imaginary line leading from the leading edge to the trailing edge of the wings) and the relative wind. The angle of attack is dependent on the shape of the airfoil, including its platform and aspect ratio. At a high angle of attack, the airflow over the wing is disrupted, and at the critical angle of attack, the airflow over the wing is disrupted enough to inhibit lift, resulting in the nose of the aircraft falling. The critical angle of attack for an airfoil never changes, but factors like weight, control surface configuration, and load factor, can change the airspeed at which an aircraft can stall.

In a stall, lift drastically decreases, which is reflected by a sudden pitch down of the nose of the aircraft. This can feel like the aircraft is falling and has no lift, but it is actually just a decrease in lift and a change in the aircraft’s level. A stall can be accompanied by a roll or yaw to one side if the aircraft is uncoordinated. If this happens and recovery procedures are not initiated, the aircraft can enter a spin, which is much more difficult to recover from.

In a stable aircraft, the nose dropping is often enough to regain the proper amount of lift for the airfoil. If this happens the aircraft is easily recoverable just by lowering its pitch attitude and increasing airspeed. Unstable aircraft, however, have more difficult stall-recovery requirements.

Stalls typically occur at slow airspeeds. For this reason, slow-speed flight, especially during approach and departure, are critical phases of flight, and pilots must be very careful during these moments to prevent a stall. However, stalls can occur at any airspeed, regardless of altitude.

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find all the airfoil parts and horizontal stabilizers for the aerospace, civil aviation, and defense industries. For a quick and competitive quote, email us at or call us at 1-919-348-4040.

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If you’re a novice with boating, but are interested in delving deeper into the field, it’s important to learn certain basics of how different boats use different mechanisms to function. A good place to start would be with smaller water jet driven boats. If you’ve ever surveyed a lakeside, you might have seen the jet driven boat at work. Look closely enough and you can see that water is being driven out from the jet placed behind the boat. This is basically how the boat is able to propel itself forward. You can find a basic and helpful description of this marine jet drive part below.

The waterjet is a mechanism that can create a propulsive thrust when water is forced in a rearward direction. The mechanism works in relation to Newton’s Third Law of Motion, which states that every action has an opposite and equal reaction. The discharge of a high velocity jet stream generates a reaction force in the opposite direction, which is transferred through the body of the jet unit to the craft’s hull, propelling it forward. Put in simpler terms, in the same way that a pistol has a recoil every time it fires a bullet, the jet experiences a forward thrust when it pushes water backwards. A deeper look into the mechanism will show you that water enters the jet unit intake on the bottom of the boat and is accelerated through the jet unit and discharged through the transom at a high velocity.

Jet drive boats have many benefits to them as opposed to stern driven boats because they are often more efficient with a steering effect that provides 360° thrusting ability for docking, and in addition, offers the flexibility to work with multiple different water jets. On top of that, jet driven boats are often smoother, quieter, and require much less maintenance than other drive shaft parts. For more information on water jet engines, rudder parts and other boating details, contact the team at Buy NSN. 

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find all the unique parts for the aerospace, civil aviation, and defense industries. For a quick and competitive quote, email us at or call us at 1-714-705-4780.

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Each model of aircraft is uniquely suited to its intended application. Regardless of what functions an aircraft has to serve, a commonality across all aircraft is the need for reliable landing gear. Aircraft landing gear come in two distinctions: fixed gear and retractable gear. As with any aircraft component, each type has its advantages and disadvantages. This blog will provide an explanation of basic aircraft landing gear types, their features, and functionalities.

Fixed gear landing equipment is advantageous due to its low cost, simplicity, and the fact that it is perpetually deployed. It’s always there, so the pilot will never need to worry about malfunctions while lowering the landing gear. However, this also creates drag which slows the plane and hinders its overall performance. Retractable landing gear is designed to hide the landing gear in the fuselage of the aircraft during flight. This increases aerodynamics allowing for better performance, higher airspeed, and decreased drag. The biggest disadvantage of this landing gear is its weight, cost, and lack of availability to the average consumer. Retractable landing gear is typically limited to high-performance or military aircraft.

For the average aviator, fixed gear is going to be the best choice. Within the family of fixed gear landing equipment, there are two main designs: conventional, or tailwheel, and tricycle. Conventional landing gear features two main wheels slightly ahead of the plane’s center of gravity and a third wheel in the rear for stability. As its name would suggest, it is the most commonly used landing gear. Think of tricycle landing gear as the opposite of conventional. This configuration has the main wheels in the rear and a stabilizing third wheel in the front. This allows pilots to apply more pressure to the brakes upon landing without the risk of the plane nosing over.

Aircraft with fixed gear landing on water or snow can affix pontoons or skis to their fixed landing gear, and some planes, called flying boats, are even built so the fuselage itself is buoyant enough to land on water. Regardless of your aircraft or landing gear type, Buy NSN has the products every aviator needs.

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find all the unique parts for the aerospace, civil aviation, and defense industries. For a quick and competitive quote, email us at or call us at 1-919-348-4040.

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When we think of aircraft functionality, we tend to forgo the importance of the wheels and brakes. Although the main functionality of aircraft is to fly, wheels and brakes are what enable the aircraft to both start movement, and safely land at their various destinations. They are expensive and important components, and often are subjected to great deterioration with every flight. With wear and tear of any aerospace part comes the need for maintenance, repair, and overhaul (MRO).

Wheels and brakes find the need for MRO services once the tire tread or brake friction becomes worn to limit. These components have the ability to be replaced a certain number of times before they should undergo full overhaul for safety. Intervals are set to limit the amount of changes that a tire can undergo before a full overhaul is required, and brakes follow a similar schedule. Despite these guidelines, many operators neglect overhaul and stick to simply changing their tires, often leading to great corrosion that can cause the unit to become irreplaceable. Overhaul is important as corrosion is a major problem with environmental extremes that parts are subjected to during constant use.

Contrary to popular belief, it is the sharp turns during operation that wear a tire and brake system more than the aircraft landing process. Factors that also decrease the life expectancy of tires and brakes include increase of flights during the summer and thus hot conditions and runways, as well as compact inner city airports. Improvements and breakthroughs of tire and brake technology on newer aircraft are helping to steadily increase life expectancy. Nevertheless, legacy aircraft with unchanged technology have long lifespans and continue to have great wear and tear with their continued use.

Independent MRO services are quickly growing as a competitor to original equipment manufacturers around the world, especially for smaller airlines and those that operate with mixed wheel and brakes. With these airlines, independent MRO serve a better opportunity for servicing their fleets and operations. Nevertheless, with each flight, aircraft come closer and closer to the need for servicing.

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find aircraft parts including the wheels and brakes you need, new or obsolete. For a quick and competitive quote, email us at or call us at +1-919-348-4040.

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The aerospace and defense industries are hectic industries that require a lot of information to be shared in a small amount of time. Part sourcing needs to be quick and efficient in order to accommodate for costly situations such as Aircraft on Ground (AOG). The NSN system was developed by the U.S. Department of Defense and is a key reason why the federal supply chain runs so efficiently today.

The premise behind the National Stock Number (NSN) system is uniformity and a set standard of communication. During WWII, the military found it difficult to quickly and efficiently source parts from manufacturers as there was no formal naming system. A part could have multiple names depending on the manufacturer that made it. This lack of a formal naming system led to inconsistencies in stock levels as there would be a surplus of components in one area and a deficit in another. In response to these issues, the DoD set out to form a uniform system that could be understood across countries with language barriers.

The key part of the NSN system is the 13-digit identification number that is assigned to all components that are sourced, stocked, and procured within the federal supply chain. NSNs are made up various subcategories that each provide more information about the individual component. The first four digits of the NSN are known as the federal supply group classification code (FSCG), which is further broken down to the federal supply group (FSG) and the federal supply class (FSC). The FSG is the first two numbers of the NSN and details which of the broad groups the component belongs to. In the aerospace industry federal supply group 15: aircraft and airframe structural components is important. The following 2-digits are the federal supply classification, which is the exact sub-category that the component belongs to. FSCG 1510 is under FSG 15 and includes fixed wing aircraft components.

The remaining nine digits of the NSN include the 2-digit country code and the 7-digit National Item Identification Number (NIIN). The NIIN is a random number assigned to the component, unlike the FSC or FSG the NIIN doesn’t further classify an item. A NIIN more or less tells you what the item is. The DLA uses a sequential system to generate the NIINs. It is possible to source parts using their NIIN, however it is more common to source parts using the full NSN.

NSNs and NIINs are not necessarily something to compare, but rather understand how they work together to identify an individual component. Without NSNs or NIINs it would be very difficult to tell one fastener from the next for example. Even larger aircraft components such as landing gear assemblies benefit from a clear naming system. Buy NSN stocks many different NSNs and NIINs that are all helpfully categorized on our website,

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A piston is part of a reciprocating engine with the purpose of transferring the force from the expanding gases in the cylinder to the crankshaft. In steam  reciprocating engines, valves are necessary to control the entry and exit of gases at the proper time in the piston’s cycle to ensure the engine is functioning properly. Piston engines mounted on aircraft have utilized several different types of valves over the years.

Sleeve valves were first patented by Charles Yale Knight, and were initially used in luxury automobiles such as Mercedes-Benz and Peugeot. Early sleeve valves used alternating twin sliding sleeves, but those used in aircraft, notably by Bristol, used a single sleeve that rotated around a timing axle set at 90 degrees to the cylinder axis. Named the Burt-McCollum valve after the two inventors that developed it separately, the greatest advantage of the sleeve valve was its mechanical simplicity and ruggedness, as well as consuming less oil than other sleeve valve designs. Sleeve valves were frequently used in both aircraft and automobiles up until the 1940s, when their replacement was introduced.

Poppet valves, also known as mushroom valves, control the timing and fuel quantity flowing into an engine like any other valve. Poppet valves operate the marionette as they move in response to remote motion transmitted by the engine, and instead of sliding or rocking over a seat to uncover a port the way that sleeve valves do, they lift in a movement perpendicular to the port. Because there is no movement in the seat, there is no need for lubrication. The issue with piston poppet valves lies in metallurgy and heat management.

In the early days of poppet valves, the metal used to make poppet valves was not resilient enough, and the rapid opening and closing of valves would cause the cylinder heads to rapidly wear out. This meant that the poppet valves would need to be re-ground every two years or so, causing high maintenance costs. Modern poppet valves are made from high-quality stainless steel, which averts this issue. Overheating was also a serious concern, causing excessive piston valve wear and defective sealing. This was solved by adding valve cooling systems, as well as sodium-filled valve stems that acted as a heat pipe to divert heat away from the valve head.

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Like other forms of aviation technology, aircraft propellers are not fixed and unchanging, but instead evolved, changed, and improved over the years, developing into different types depending on the needs of their users. In this blog, we will break down and examine some of the most common types of propellers.

The first type of propellers developed were fixed pitch propellers. As their name implies, fixed pitch propellers cannot change their pitch (the angle the propeller blades face) and are typically made from a single piece of material. Fixed-pitch propellers were first made from wood, in the years before World War 2. Wooden propellers are not carved from a single piece of wood, but instead five or more separate plies of wood that are laminated together to prevent warping.

Modern innovations have created other types of propellers. The first are controllable pitch propellers, which have a hydraulic system built into the propeller. This allows the pilot to adjust the pitch of the propeller while in flight, which gives them more control over the handling and flight characteristics of the aircraft. Propeller adapters also have a big advantage over some traditional propellers. 

Constant speed propellers use hydraulic or electrical means to adjust the blade pitch, which lets them compensate for increased or decreased power. This occurs automatically, so that if engine power increases the blade angle increases as well, and if the engine power decreases the blade angle decreases to match it. This is done to keep engine RPM constant, which improves the engine’s health.

Two-position propellers have two preset pitch angles that the pilot can switch between freely while in flight. Reversing propellers are constant speed propellers that are able to add negative pitch to the blades, which produces negative thrust, and effectively turns the propeller into a brake of sorts. This is used to shorten the amount of runway needed when landing larger aircraft.

Full feathering propellers are constant speed propellers that have the ability to turn in the wind in the event of engine failure. This helps eliminate drag and windmilling.

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When it comes to connecting components together within an aircraft, sturdiness is key. The two components should be solid and continuous, without any wiggle room. Under no circumstances should the coupling experience any sort of vibration. In general, vibrations jeopardize the strength and tension of a fitting or joint. While it may seem like a comfort issue, vibration can actually cause significant damage to the hardware of an aircraft. If a loose fitting is not adjusted the vibration can even lead to failure of the component.

One cause for vibration between hardware pieces is an incorrect balancing of the shaft coupling. Like all other aspects of aircraft systems and components, balance is a heavily regulated. A component is either balanced by a manufacturer, or it is balanced by the addition or subtraction of material during construction or maintenance. International Standards Order 1940-1:2003 outlines the balance quality requirements for rotors in a rigid state. The balance quality grade is used to define the limits of residual unbalance.

There are multiple options when it comes to correctly balancing a shaft coupling. An additional weight can be added to one side or plane only. This is known as static balancing and is typically used when the length/diameter ratio is less than one. If you were to imagine a cylinder, static balancing is the equivalent of drilling a hole in just one side. Dynamic balance is used if the length/diameter ratio is greater than one. For this balancing technique, adjustments are made to more than one area on our cylinder example.

The actual balancing of a shaft coupling can be split up in light of the placement of the shaft coupling on the aircraft. A manufacturer will cover the specified balance quality for a component. To ease assembly, components can be balanced in part, fitted, and then further balanced up to the industry standard. An alternative way of balancing a shaft coupling is to fit and balance one half of the shaft first. The other half of coupling can be assembled individually, with each of the components singularly balanced. The benefit of this way of balancing is the ability to interchange the various components of a system.

For example, individual brake discs can be removed and replaced, without having to rebalance the entire brake system. Ultimately this increases the rate of efficiency of any repair and maintenance, which in turn, mitigates the cost of aircraft maintenance. Due to their location within an aircraft or their load bearing properties, certain mechanisms dictate balancing procedures. For example, gear couplings must be balanced using a combination or sub-assembly. The relationship between the hub and the sleeve are not lined up until they are under a load, therefore any prior balancing would be incorrect.

Balance is a key characteristic of a sturdy, well-functioning system. If balance is not given the correct amount of care and attention, vibration will occur which leads to further issues down the line. 

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One of the most common, yet crucial, components in the construction of a vessel are its valves. They serve a wide array of functions ranging from regulating the flow of liquids to assisting in the operation of hydraulic lifts. However, one type of valve seems to appear more frequently than others, and that is the gate valve.

A gate valve has two variations: a rising stem and a non-rising stem. Rising stem gate valves are typically made from cast or forged steel. Its modus operandi is simplistic in that the round handle rotates a threaded shaft which is attached to its centerfold. The stem will rise as it opens the valve followed by a descent as it closes the valve. One can spot if the valve is opened or closed by observing the amount of stem that appears. A flush stem correlates to a closed valve while an exposed stem means it’s open.

The non-rising gate valve is intended to function in tight spaces, abandoning the rising stem mechanism of its counterpart. This module utilizes a rotating wheel, or handle, that turns either left or right corresponding to its opened and closed positions. When the handle is turned towards the left the valve is opened. When it’s turned towards the right it reflects a closed position. In both cases the handle is flush with the pipe as the operating processes inside are able to open and close the valve without the need to raise the stem.

Wear and tear comes naturally to these valves as they are designed to function against the current.  Proper maintenance and monitoring of these valves is critical in preserving their longevity and avoiding unnecessary leaks or malfunctions. In essence, a proactive approach proves beneficial in the long run.

A key concept to remember is that these valves are designed to be either fully closed or fully opened. An issue can arise if the measurements on the valves aren’t adequate, which will result in a change in the consistent flow of fluid.

Although these two valves are common components, they contribute a major part in the successful completion of a vessel.

At Buy NSN, owned and operated by ASAP Semiconductor, we can help you find all the valves and ship and marine parts you need; we’re always available and ready to help, 24/7x365. For a quick and competitive quote, email us at or call us at +1-919-348-4040.

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