Mechanical Drawing Symbols

This technical drawing shows the machine parts assembly using joining by threaded fasteners.
"Assembling (joining of the pieces) is done by welding, binding with adhesives, riveting, threaded fasteners, or even yet more bending in the form of a crimped seam. Structural steel and sheet metal are the usual starting materials for fabrication, along with the welding wire, flux, and fasteners that will join the cut pieces. As with other manufacturing processes, both human labor and automation are commonly used. The product resulting from fabrication may be called a fabrication. Shops that specialize in this type of metal work are called fab shops. The end products of other common types of metalworking, such as machining, metal stamping, forging, and casting, may be similar in shape and function, but those processes are not classified as fabrication." [Metal fabrication. Wikipedia]
This mechanical engineering drawing example was designed using ConceptDraw PRO diagramming and vector drawing software extended with Mechanical Engineering solution from Engineering area of ConceptDraw Solution Park.

This engineering drawing shows different types of geometry of butt welds.
"Welds can be geometrically prepared in many different ways. The five basic types of weld joints are the butt joint, lap joint, corner joint, edge joint, and T-joint (a variant of this last is the cruciform joint). Other variations exist as well - for example, double-V preparation joints are characterized by the two pieces of material each tapering to a single center point at one-half their height. Single-U and double-U preparation joints are also fairly common - instead of having straight edges like the single-V and double-V preparation joints, they are curved, forming the shape of a U. Lap joints are also commonly more than two pieces thick - depending on the process used and the thickness of the material, many pieces can be welded together in a lap joint geometry." [Welding. Wikipedia]
This engineering drawing example was redesigned using the ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: Butt Weld Geometry.GIF.
[commons.wikimedia.org/ wiki/ File:Butt_ Weld_ Geometry.GIF]
The engineering drawing example "Butt weld geometry" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

This engineering drawing present weld type symbols and fillet weld symbols.
The weld type symbol is typically placed above or below the center of the reference line, depending on which side of the joint it's on. The symbol is interpreted as a simplified cross-section of the weld.
"Fillet welding refers to the process of joining two pieces of metal together whether they be perpendicular or at an angle. These welds are commonly referred to as Tee joints which are two pieces of metal perpendicular to each other or Lap joints which are two pieces of metal that overlap and are welded at the edges. The weld is aesthetically triangular in shape and may have a concave, flat or convex surface depending on the welder’s technique. Welders use fillet welds when connecting flanges to pipes, welding cross sections of infrastructure, and when fastening metal by bolts isn't strong enough." [Fillet weld. Wikipedia]
The engineering drawing example Welding symbols is included in the Mechanical Engineering solution from Engineering area of ConceptDraw Solution Park.

"Hydraulics is a topic in applied science and engineering dealing with the mechanical properties of liquids. At a very basic level hydraulics is the liquid version of pneumatics. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on the engineering uses of fluid properties. In fluid power, hydraulics is used for the generation, control, and transmission of power by the use of pressurized liquids. Hydraulic topics range through some part of science and most of engineering modules, and cover concepts such as pipe flow, dam design, fluidics and fluid control circuitry, pumps, turbines, hydropower, computational fluid dynamics, flow measurement, river channel behavior and erosion." [Hydraulics. Wikipedia]
This hydraulic schematic example was redrawn using ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: Skjematikk.GIF.
[commons.wikimedia.org/ wiki/ File:Skjematikk.GIF]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
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The engineering drawing example "Hydraulic schematic" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow." [Directional control valve. Wikipedia]
This example engineering drawing showing the directional control valve usage with fixed volume pump and hydraulic cylinder is redesigned using the ConceptDraw PRO diagramming and vector drawing software from Wikimedia Commons file: DCV 19.jpg.
[commons.wikimedia.org/ wiki/ File:DCV_ 19.jpg]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
[creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.

This example engineering drawing showing the hydraulic directional control valve usage with floating motor and pressure compensated pump is redesigned using the ConceptDraw PRO diagramming and vector drawing software from the Wikimedia Commons file: DCV 17.jpg.
[commons.wikimedia.org/ wiki/ File:DCV_ 17.jpg]
This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license.
[creativecommons.org/ licenses/ by-sa/ 3.0/ deed.en]
"Directional control valves are one of the most fundamental parts in hydraulic machinery as well and pneumatic machinery. They allow fluid flow into different paths from one or more sources. They usually consist of a spool inside a cylinder which is mechanically or electrically controlled. The movement of the spool restricts or permits the flow, thus it controls the fluid flow. ...
The spool (sliding type) consists of lands and grooves.The lands block oil flow through the valve body. The grooves allow oil or gas to flow around the spool and through the valve body. There are two fundamental positions of directional control valve namely normal position where valve returns on removal of actuating force and other is working position which is position of a valve when actuating force is applied. There is another class of valves with 3 or more position that can be spring centered with 2 working position and a normal position. ...
Directional control valves can be classified according to:
(1) number of ports;
(2) number of positions;
(3) actuating methods;
(4) type of spool." [Directional control valve. Wikipedia]
The fluid power equipment drawing example "Directional control valve" is included in the Mechanical Engineering solution from the Engineering area of ConceptDraw Solution Park.