Monometallic diaphragm valve is used for corrosive and high temperature fluid flow control. The body, diaphragm, and plug of the valve are welded together to form an integral leakproof unit for containing the fluid as it passes through the valve from inlet to outlet

Ebihara, B. T.

Vary, A.

English

NASA Technical Reports Server

For Cooling, I-
or Pressurizin 
Assembly Clamp 
Outi Inlet 
August 1966	 Brief 66-10365 
NASA TECH BRIEF 
NASA Tech Briefs are issued to summarize specific innovations derived from the U. S. space 
program and to encourage their commercial application. Copies are available to the public from 
the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Diaphragm Valve for Corrosive and High Temperature Fluid Flow Control

Has Unique Features 
Plug Weld
	
Valve Plug 
The problem: 
Metallic, weld-sealed valves (usually of the bellows-
seal construction) used for corrosive and high tem-
perature fluid flow control, are costly to fabricate and 
are often large and cumbersome, and may not provide 
reliable pressure and vacuum-tight fluid enclosures.
The solution: 
A monometallic diaphragm valve in which the 
body, diaphragm, and plug are welded together to 
form an integral leakproof unit for containing the 
fluid as it passes through the valve from inlet to out-
let.
(continued overleaf) 
This document was prepared under the sponsorship of the National
	 Government assumes any liability resulting from the use of the 
Aeronautics and Space Administration. Neither the United States
	 information contained in this document, or warrants that such use 
Government nor any person acting on behalf of the United States
	 will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19660000364 2020-03-11T17:40:52+00:00Z
How it's done: 
Flow control is achieved by varying the position 
of the conical end of the plug with respect to its cylin-
drical inlet passage seat. The movement of the plug 
with respect to the valve body is achieved by means 
of a differential thread action provided by the two 
threaded portions of the stem. A finer thread engages 
the bonnet and a coarser thread engages the plug, 
resulting in a fine adjustment for throttling and flow 
control. A bleed passage in the valve body connects 
the cavity between the diaphragm and body with the 
outlet or low pressure side of the valve. The cavity 
between the diaphragm and the bonnet is tapped for 
venting, or for pressurizing to counter the internal 
pressure if necessary. In addition, the bonnet side of 
the diaphragm can be heated or cooled by means of 
these inlet and outlet passages provided in the bonnet. 
The body, plug, and diaphragm are welded together to 
form a pressure- and vacuum-tight fluid enclosure, 
and the bonnet is sealed by gaskets or packing. The 
diaphragm is formed from thin plate and series of 
annular convolutions are die stamped into it to en-
sure ease of flexure. 
Notes: 
1. Many alternate embodiments may be made in the 
basic valve design and particularly in the dia-
phragm movement. Coarser action may be attained
by reversing the threads on the stem. The shape 
of the plug and seat may be altered for different 
fluids and flow rates. An alternate valve design 
incorporating a pneumatic positioner that imparts 
an axial motion to the stem is preferable in cases 
where galling or seizing of the differential threads 
in the bonnet and plug are likely. 
2. Monometallic diaphragm valves of 321 stainless 
and HS25 (L605) have been fabricated and success-
fully tested at temperatures up to 1000°F in a 
two-phase mercury system. A version of this valve 
will be used in a two-phase potassium system at 
temperatures of about 1300°F. 
3. The body, diaphragm, and plug may all be mono-
metallic to prevent differential cell corrosion. 
4. Inquiries concerning this innovation may be di-
rected to:
Technology Utilization Officer 
Lewis Research Center 
21000 Brookpark Road 
Cleveland, Ohio 44135 
Reference: B66-10365 
Patent status: 
No patent action is contemplated by NASA. 
Source: Alex Vary and B. T. Ebihara 
(Lewis-304) 
Brief 66-10365	 Category 05


Diaphragm valve for corrosive and high temperature fluid flow control has unique features

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server