Week 14 challenge

AIM:

To design a butterfly valve and apply to apply GD&T symbols to the drawing and finally to apply all the parts in the butterfly valve to make it as one assembly file and the assembly consist of all the parts. this process are done by using Siemens NX cad.

DESIGNING SOFTWARE:

Siemens NX cad 12.0.1

INTRODUCTION:

A butterfly valve is from a family of valves called quarter-turn valves. In operation, the valve is fully open or closed when the disc is rotated a quarter turn. The "butterfly" is a metal disc mounted on a rod. When the valve is closed, the disc is turned so that it completely blocks off the passageway.Butterfly valves are used where space is limited. Unlike gate valves, butterfly valves can be used for throttling or regulating flow as well as in the full open and fully closed position. The pressure loss through a butterfly valve is small in comparison with the gate valve.Butterfly valves are often distinguished by the three main types: zero, double, or triple offset.There are several standards available worldwide that describe the symbols and define the rules used in GD&T. One such standard is American Society of Mechanical Engineers (ASME) Y14.5. This article is based on that standard, but other standards, such as those from the International Organization for Standardization (ISO), may vary slightly. The Y14.5 standard has the advantage of providing a fairly complete set of standards for GD&T in one document. The ISO standards, in comparison, typically only address a single topic at a time.

COMPONENTS ARE IN THE BUTTERFLY VALVE:

• BODY
• SHAFT
• RETAINER
• DISC PLATE
• LEVER HANDLE
• NUT

BODY:

The one of the major component in butterfly valve is body that is fit between two pipe flanges. The following sets of the command used for Body designing in NX CAD

• Sketch
• Extrude
• Counterbore

SHAFT:

In order for the disk to be held in the proper position, the stem must extend beyond the bottom of the disk and fit into a bushing in the bottom of the valve body.The disc plate and lever are assembled to this shaft.

RETAINER:

Retainer is a kind of washer fixed on the body of butterfly valve. Butterfly valves comprise a valve seat comprising a generally S-shaped cross-section and a valve seat retainer configured with appropriately shaped cooperating surfaces.

DISC PLATE:

When valve is fully opened or closed the disc is rotated a quarter turn.Disc is mounted on shaft. When the valve is closed, the disc is turned so that it completely blocks off the passageway.When the valve is fully open, the disc is rotated a quarter turn so that it allows an almost unrestricted passage of the fluid.Two methods are used to secure the disk to the stem so that the disk rotates as the stem is turned. In the first method, the disk is bored through and secured to the stem with bolts or pins. The alternate method involves boring the disk as before, then shaping the upper stem bore to fit a squared or hex-shaped stem. This method allows the disk to "float" and seek its center in the seat. Uniform sealing is accomplished and external stem fasteners are eliminated. This method of assembly is advantageous in the case of covered disks and in corrosive applications.

LEVER HANDLE:

Lever is mounted at an end of shaft outside the body. Hand lever is usually used in small sized Butterfly valves.Basically lever handle is used to open and close the Butterfly Valve. It provides ease of operation at the expense of speed. It can be adjusted to various positon with the help of the gearbox.

NUT:

It is fixed at the top end of shaft to keep the lever and retainer on position. It is used to hold the component at the same position to add some threads inner side of the nut to make the nut stronger to hold the component.

ASSEMBLY OF THE BUTTERFLY VALVE:

In the assembly we will put all the components in the one assembly file and use the move command to move the object in the respective place and use the certain commands to constrain all the components together and made the one complete assembly of butterfly valve the mainly use the commands they are

• Infer center/axis
• Touch
• Align

FINAL OUTPUT OF THE ASSEMBLY:

CONCLUSION:

To design a butterfly valve and to apply the GD&T to the drawing and assemble all the parts by using Siemens NX cad 12.0.1 is successfully completed.