Creator:H.A. Bowman and D.P. Johnson
Date Created:July 1957
Place Created:
Keywords:high pressure gage,
Context:construction and assembly instructions from National Bureau of Standards
**************************************************
NATIONAL BUREAU OF STANDARDS REPORT
5381
THE DETAILS OF CONSTRUCTION AND ASSEMBLE" OF THE NBS DESIGN MANGANIN HIGH PRESSURE GAGE
by
H. A. Bowman D. P. Johnson
Report to
Watertown Arsenal and Watervliet Arsenal Ordnance Corps, Department of the Amy
NBS
U. S. DEPARTMENT OE COMMERCE NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS
Functions and Activities
The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended hy Congress in Public Law 619, 1950. These include the development and maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials, devices, and structures; advisory services to Government Agencies on scientific and technical problems; invention and development of devices to serve special needs of the Government; and the development of standard practices, codes, and specifications. The work includes basic and applied research, development, engineering, instrumentation, testing, evaluation, calibration services, and various consultation and information services. A major portion of the Bureau's work is performed for other Government Agencies, particularly the Department of Defense and the Atomic Energy Commission. The scope of activities is suggested by the listing of divisions and sections on the inside of the back cover.
Reports and Publications
The results of the Bureau's work take the form of either actual equipment and devices or published papers and reports. Reports are issued to the sponsoring agency of a particular project or program. Published papers appear either in the Bureau's own series of publications or in the journals of professional and scientific societies. The Bureau itself publishes three monthly periodicals, available from the Government Printing Office: The Journal of Research, which presents complete papers reporting technical investigations; the Technical News Bulletin, which presents summary and preliminary reports on work in progress; and Basic Radio Propagation Predictions, which provides data for determining the best frequencies to use for radio communications throughout the world. There are also five series of nonperiodical publications: The Applied Mathematics Series, Circulars, Handbooks, Building Materials and Structures Reports, and Miscellaneous Publications.
Information on the Bureau's publications can be found in NBS Circular 460, Publications of the National Bureau of Standards (11.25) and its Supplement ($0.75), available from the Superintendent of Documents, Government Printing Office, Washington 25, D. C.
Inquiries regarding the Bureau's reports should be addressed to the Office of Technical Information, National Bureau of Standards, Washington 25, D. C.
NATIONAL BUREAU OF STANDARDS REPORT
NBS PROJECT	NBS REPORT
SHiSilS	July 1957	5381
0602-20-3623
THE DETAILS OF CONSTRUCTION AND ASSEMBLY OF THE NBS DESIGN MANGANIN HIGH PRESSURE GAGE
1*
H. A. Bowraan
and D. P,Johnson Mechanical Instruments Section Mechanics Division
Report to
Watertown Arsenal and Watervliet Arsenal Ordnance Corps, Department of the Any
U. S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS
The publication, reprinting, or reproduction of this report in any Form, either in whole or in part, it prohibited unless permission Is obtained in writingfrom theOffice of the Director, National Bureau of Standards, Washington 25, D, C. Such permission is not needed, however, by a Government agency for which a report has been specifically prepared If that agency wishes to reproduce additional copies of that particular report for its own use.
FOREWORD
This report describes in detail the construction of a type of manganin wire pressure gage used successfully by the National Bureau of Standards for measurements of pressures up to 200,000 pounds per square incho
The work was conducted in connection with a program for the improvement in techniques of high pressure measurements, supported initially by the Watertown Arsenal (Order No. TR3-3002) and later by the Watervliet Arsenal (Order No. TR3-0110),
W« Ramberg, Chief Mechanics Division
E. C. Lloyd, Chief Mechanical Instruments Section
THE DETAILS OF CONSTRUCTION AND ASSEMBLE OF THE NBS DESIGN MANGANIN HIGH PRESSURE GAGE
by
Ho Ao Bowman and D0 P0 Johnson
lo INTRODUCTION
Tha NBS design manganin wire high pressure gage, Figure ljhas given eatisfactory service to pressures of 200,000 pei in use over an extended period of time at the National Bureau of Standards0 This report provides detailed instructions for the fabrication of the various members of the gage, and a step-ty-step description of the assembly of these members into the completed unito Although not strictly a part of the gage assembly, there are described certain tools which facilitate the removal of the gage from the high pressure vessels
The historical development of the gage, its calibration, methods of use, etCo, are not reported on here since such topics are adequately covered elsewhere in high pressure literature (see bibliography at end of report)e Also discussion of choices of materials and configurations are not included except insofar as are necessary to the proper understanding of the fabrication and assembly processa
The NBS gage is essentially a ^terminal manganin wire resistor immersed in the high pressure fluid in a configuration wherein strains, other than hydrostatic, are nd.nimi.zeda It is designed to be contained in a Harwood Engineering Coapaiy high pressure vessel (Harwood drg D1082),
and hence the Harwood jam nut (Harwood drg B1100) associated with the vessel is an integral part of the gageQ This gage may be housed in any high pressure vessel with a bore one inch in diameter, 3 3A inches long, and whose jam nut contains a hole 1/2" in diameter <>
For purposes of discussion the fabrication of the complete gage is divided as followst
ko The ceramic mandrel B« The manganin coil and its leads Co The high pressure electrically insulated header Do The assembly of the gage Eo Insertion for pressure seasoning Fo Removal of the gage from the high pressure vesselo 20 FABRICATION OF THE CERAKIC MANDREL The mandrel is made of steatite (Qeneral Ceramics Company, type BN 3030) which may be formed into precisely dimensioned parts 0 It is obtained in the form of one=inch diameter rods which a re first machined as shown in Figure 2» Upon completion of this lathe job, sereral small (No> 80 drill) holes are drilled in the end shanks, and floors of the grooves in order that the various wire members of the coil may be held firmly in place0 The approximate locations of these holes are shown in Figures 3a and 3b 0 A hole is drilled in the floor of each groove at the upper end of the mandrel, and one hole is drilled in the wall of the shank at this endo The shank hole and one floor
bole are shown in figure 3a« Care must be exercised in drilling the shank hole to avoid breaking through the inner wall of the shank. At NBS these holes are drilled by hand with the No. 80 drill in a pin vice, it having been found that fewer green (i.e. unfired) steatite mandrels are broken when drilling by hand rather than with drill press and drilling jig. At the base end of the mandrel, four such shank holes are drilled, two on each side of the shank. Again, a single hole is drilled in the floor of each of the two grooves. Figure 3b shows two of the shank holes and a floor hole<>
The steatite mandrel is next fired in a ceramic kiln as follows: lo Increase temperature at the rate of 2*C per minute
until a temperature of 1270*C is attained0 20 Hold this temperature for one hour0 3o Allow the furnace to cool slowly to room temperature (about 16 hours cooling time). This schedule was worked out to reduce the green mandrel to a fairly dense unit with near zero porosity0 The success of firing is easily checked by placing a small drop of Skrlp fountain pen ink on the fired surfaceo If the ink remains in a small well defined spot the firing cycle was successful. If, on the other hand, the ink disperses, the material is still porous <, It should be pointed out that the manufacturer of green steatite rod will usually fire the rod which they have made when requested by the purchaser, in which case, proper firing is almost certainly assuredo
• u -
During the firing process, the mandrel will shrink about 16% radially and 8% longitudinally with respect to the axis of the original green rodo
30 FABRICATION OF THE MANGANIN COIL
The wire sensing element coil is made of B+S No. 36 (<>00£n diameter) manganin wire which is Insulated by a double layer of silk® Depending upon the melt, it will have an ohndc resistance of U-1/2 to 12 ohms per footo Two lengths of wire are cut, each having a resistance of one-half of the desired total resistance of the completed unit plus about 2°*l/2% plus 3A inch to allow for heat treatment and trimming o
These two pieces are formed into helices by winding, with turns touching, on a highly polished length of 3/6U" diameter drill redo Winding tension should be 8 to 10 ounces, and the outside diameter of the finished helix will be about 0.065". When the helix is removed from the mandrel a l/2n length should be bared at one end and a l~lA" length at the other. Each wire is then stretched so that the helical portion is equal to about 3A" 1«®8 than is required to fill one of the spiral grooves in the ceramic mandrelo They are then mounted on the mandrel, passing the l/2n bare length through the hole in the floor of the groove at the base end of the mandrel, and the 1-lA" bare end through the floor hole at the opposite end. No effort should be made to stretch the helix to fill the entire length of the groove« Four short (about 1-1/2") lengths of 0o010n diameter gold
 5 -
wire are threaded through the #80 holes In the base end shank of the mandrel, and two are silver brazed to each free end of manganin at this end (see Figure 3b )0 This brazing process is best performed by a gas oxygen flame rather than a gas-air flame, since the higher temperatures thus developed will cause the silver brazing alloy to flow out more quickly, so there is less chance for damage to the manganin wire0
The brazing alloy bead should be rather large, and the three wires (2 of gold and one of manganin) which protrude from this bead should be separated by large angles<> This eliminates any possibility of inter-mlttent short circuiting of the leads in the immediate vicinity of the
beado
In this brazing process borax flux is used which may be removed by immersing the entire mandrel in boiling water for several minutes 0 The mandrel should be rinsed in another container of boiling water 0
The mandrel and the supported wires are next placed in an oven at 130* C to 1U0*C for U8 hours, during which interval the resistance will decrease by somewhat less than 2% and the length of each helix will be increased by about 3A"« This slack may be taken up at the upper end of the mandrel, and each helix should now fill its groove almost perfectly0 It is not desirable that the helix be wrapped tightly around the mandrel, so the free end of the manganin at the upper end of the mandrel should be adjusted in length to allow a slight amount of play of the helix0 Ordinarily about 1/2 to 3A inches of wire will have to be removed from each piece0
« 5 **
One of the two free ends of manganin should be passed through the
hole In the upper shank, and the two free ends silver-brazed together
as shown in Figure 3a0 The flux removal in this step is accompolished
by playing a tiny stream of near-boiling water directly upon the flux
covered brazing bead taking great care to prevent any wetting of the
rest of the assembly®
The overall coil resistance should now be slightly above the
desired final resistance0
Uo FABRICATION OF THE ELECTRICALLY INSUIATED HIGH PRESSURE HEADER
This member of the NBS high pressure gage assembly is made up of
several individual elements which will be taken up individually0
Ao MA.IH BOOT o This element is made of Vega Tool Steel (manu»
factured by the Carpenter Steel Company) and is hardened to
Rockwell C57 to C59o The finished dimensions are shown in
Figure Uo Unless otherwise indicated, tolerances of ±.003"
are satisfactory. Requirements for finishing surfaces and
corners are shown in Figure So Where no other requirement is
called for NBS practice has been to grind exterior surfaces to
a finish of 32 raieroinches, The element should be carefully
checked for hardness after heat treatment and prior to the
performance of any finish grinding,, A radius (o00f>" - o010")
should be left on all cornerso
Bo INSUIATING BUSHING,, These bushings, Figure 6, have been made
from a number of materials (sapphire, quartz, etc0) all of
which work satisfactorily,, Present Bureau practice is to use
Solenhofen Lithographic limestone. This material machines
>
well; however, it should not be heated daring machining since it is believed that the physical characteristics may be unfavorably altered by such heating0
After machining, the completsd bushing is immersed in melted paraffin at a temperature of about 125°C. This temperature is maintained for several minutes and the paraffin Is allowed to cool to solidification, at which time the bushings are removed from the cold paraffin with a knife. Paraffin remaining on the surface of the bushing and in the hole is removed by scraping (not heating)0 This process is intended to replace part of the water contained in the i rrt er-crysta1line spaces by paraffin and reduce the surface conductivity0 THE EIECTRODEo These elements are made of cold rolled steel as shown in figure 7. In step 1, effort should be made to have the gold wire emerge from the pool of silver brazing alloy near the longitudinal axis of the cold rolled steel rod. In step 2, the piece is chucked up in a four jaw chuck and aligned so that the emergence of the gold from the brazing alloy is near the longitudinal axis of the .17U" surface to be turnedo In step 3, the piece is chucked up on the .17U diameter, cut to length and the finish-machining performed as indicatedo
Do OUTER EXTRUSION RING. This square cross section ring fitting on the .815" diameter of the main body, Figure U, is made of annealed 18-8 stainless steelo Its I.D. is ?8l8n and its 0oD„ is »998"o Its length is .090" (all dimensions ±*001")o E0 O-RINGSa The small O-rings in the packing socket, Figure 8, are lA" OD x 1/8" IDo The large O-ring, adjacent to the outer extrusion ring, Figure U, is 15/16" OD x 3A" IoD0 Both rings are commercially available (these are both standard sizes) in numerous materials0 They should be made of a compound which is not affected by the hydraulic fluid to which they will be exposad0
Fo EXTRACTION BOUe This element, Figure 9A, is made of 3/16" x 9/l6" stainless steel tubing. After machining as shown, a flat is milled on the 1/2" diameter and a U-terminal soldering strip is attached as shown in Figure 9B.
So FINAL ASSEMBLY OF THE GAQE This process is best performed in the following steps:
lo Sweat lU" lengths of stranded #28 copper wire (teflon insulated) into the No0 70 hole in the electrode elements of the insulating high pressure header. Use 50-50 lead-tin rosin-core solder for this purpose. The outside diameter of the teflon insulation should be no greater than .050" (since it must pass through the hole in the bushing and the No. 55 holes in the main body of the header, see Figure 8).
The teflon insulation on the Hi" length of wire is worked up the wire until it is flush against the tip of the electrode and no wire is visible (see Figure 8)« A limestone bushing is slipped over the free end of each wire and run up to the tapered surface of each electrodeo One of these wire-electrode-bushing assemblies is placed in each of the four packing sockets in the main body of the header as shown in Figure 8«
A lA" * 1/8" O-ring is inserted between the exposed portion of the electrode and the „283n diameter section of the packing socket» This will require care to avoid bending or breaking the gold wire attached to the end of the electrode„ The 1/8" 10 O-ring is stretched over the end of the electrode which causes the OD of the O-ring to become greater than the »283n space allotted„ Hence, when the O-ring is forced into this opening a tight seal is formedo
A 1/2" x 20 TPI nut is placed on the extraction bolt, Figure 9, followed by a Harwood Engineering Coapaiy jam nut to fit their high pressure vesselo The four teflan insulated wires protruding from the base of the main body of the header are pushed through the hole In the extraction bolt, and this bolt is firmly screwed into the main body base threads 0
 10 -
8. The ends of these four teflan insulated wires now protrude from the upper end of the extraction bolt, and they are soldered to the U"terminal soldering strip attached to the upper end of this bolt as shown in Figure 9B«
9« Check the insulation resistance of each circuit to ground by a megohm bridge. It should be at least 1000megohms In each circuito
10. The following procedure is important and should be carefully followed. The final step in assembly is the attachment of the coil} however, the electrical resistance of each of the four circuites to ground should be checked out under pres-sura<> The method of inserting and removing the coil from the pressure vessel are described in sections 6 and 7 of this report. A megohm bridge should be used in the measure-mentSo The insulation resistance should increase from 1000 megohms with increasing pressure (probably due to the deformation of the 0-ring). Use only non-conducting fluids such as gasoline or varsol. When it is established that the header functions properly under pressure the coil mandrel may be attached to the main body of the header by a U-li0 machine screw with the base end of the mandrel adjacent to the header. After trimming to a convenient length the four gold leads protruding from the shank holes in the mandrel base are fused to the four gold leads attached to the header electrodes using a very hot gas-oxygen flame0
No flux is necessary. These gold-to-gold fusion junctions are shown in figure 3bo This fusion should be performed as rapidly as is possible to avoid any unnecessary heating of the assembly*) 60 INSERTION FOR PRESSURE SEASONING The insertion of the assembly into the high pressure vessel is readily accomplished and requires no tools® To do thisp the following steps are followed1
lo Place an annealed stainless steel extrusion ring on the
o8l5 diameter of the high pressure header main body. 2o Follow this extrusion ring with a 15/16" x 3A" O-ring. When this O-ring is stretched onto the main body of the header, its outside diameter will be increased enough to make a slight interference fit with the I.D. of the pressure vesselo 3. Slide the jam nut back up to the upper end of the
extraction bolt in order that the operator may visually check on the process, and push the main body of the header into the 1" I.D. portion of the pressure vesselo U« Slide the jam nut forward (well lubricated) and screw it all the way home. If everything is fitted together properly, no wrench will be required0 Several applications of pressure should be applied to the manganin coil to well above the anticipated working pressure range. The coil resistance at atmospheric pressure should be noted between each high
pressure application,} There is a slight decrease in this atmospheric pressure resistance between the first few high pressure applications, however, this resistance valve will eventually become stable, at which time the coil may be assumed to be pressure seasoned. This "pressure seasoning" should be performed at a pressure as high as convenient, but in no case should it be less than 120,000 psio
If the manganin coil resistance at atmospheric pressure becomes fixed at a value lower than desired, it can be increased by slightly scraping the loop of wire at the upper end of the mandrel. If it stabilizes at a value higher than desired, this loop of wire may be shortened, however, this latter procedure may alter the coil characteristics due to the high temperatures imposed when silver brazing the wires together again.
7o REMOVAL OF THE QAGE FROM THE HIQH PRESSURE VESSEL When the gage is finally installed In its pressure vessel, it should not be unnecessarily removed0
With the proper tools, removal is easy. A slotted spacer made of cold rolled steel, Figure 10, is placed around the extraction bolt and its base rests upon the top of the Harwood jam nut. The 1/2" x 20 TP1 nut on the extraction bolt is run down lightly against the top of this slotted spacer. With one wrench holding the spacer from rotating, a second wrench is used to back the jam nut out of the vessel. After several turns of the jam nut the assembly becomes loose and may be removed by hand. Caution: Do not attenpt to remove the
=> 13 -
slotted spacer until play In the extraction bolt indicates that the
r
main body of the header has been withdrawn from the square cross section extrusion ring0 This should occur after the assembly has been raised 1-3A" by jam nut rotation0
When the gage assembly is removed in this manner, the stainless steel extrusion ring and the 3AM * 15/16" O-ring will ordinarily be left in the vesselo A bent wire hook can be used to lift out the O-ring, however, the extrusion ring will remain tightly wedged against the pressure vessel IoDo since the high pressure applications usually expand the OD of this ringo The extrusion ring extraction tool, Figure 11, will remove this ring in a minute or two0 Although the gage assembly nay be jacked out of the high pressure vessel by the contained hydraulic pressure, the mechanical shock on the manganin coil may have an adverse effect on its characteristics, hence, for the removal of the gage assembly, the procedure outlined herein is recommendedo
8. FINAL CHECK-CUT Prior to calibration of the gage by any of the methods listed in the bibliography, the following check-out procedure should be conducted:
A. The resistance between ground and any of the four lead wires should be a minimum of 250 megohms0 This is equivalent to a minimum resistance of 1000 megohms for each individual circuit previously measured (section 5-10)0
. lu -
If the resistance is appreciably less than this amount the gold wires to the coil should be cut (th«y may bs easily fused together again) and the resistance of each circuit rechecked to determine the malfunctioning circuito The trouble, if argr, will frequently be a partial short circuit between the lead wire and the header main body due to slippage of the teflon insulation away from the electrodes (Note that Figure 8 shows this insulation abutting the electrode)0 Another possibility of trouble is that certain portions of the assembly have become wet by atmospheric moisture or by water. This may be corrected by insertion of the assembly in a dessicator or it may be baked for several hours at 50°Co
Moisture in the assembly may exist but not affect insulation resistance The assembly, when attached to a Mueller Bridge shows the presence of such moisture by causing a "wet kick" on the galvanometer associated with the bridge0 Under such circumstances, when the bridge battery is keyed into the circuit, the galvanometer will exhibit a violent deflection in one direction, followed by a slow drift in the opposite direction. It is frequently possible to correct this difficulty by washing the moisture away from the assembly (by alcohol for example). If this fails a dessicator or heat should be used as explained above0
 15 -
BIBLIOQRAPHI
For readers interested in other phases of the manganin wire high pressure gage art, the following references are cited.
Subject Historical Development
Manganin Gage Construction
Calibration vsa Piston Gage
vso Water Freezing
(1)
(2) (3)
(U) (5)
vs0 Mercury Freezing (6)
Pressure Seals in NBS (7) Gage
Reference
"The Physics of High Pressure", Po Wo Bridgmen, G» Bell & Sons, London, 19U9, ppo 70-71o
Ibid, pp. 72-73o
"Construction and Properties of the Manganin Resistance Pressure Gage", Adams, Goranson and Oibson, RoSolo fly 230 (1937).
"The Piston Gage as a Precise Measurements Instrument", Johnson and Newhall, ASME, 75, 3, 301 (1953)o
"The Utilization of the Phase Transition Between Water and Ice VI in the Calibration of a Manganin Wire Pressure Gage, NBS Report U378, Bowman, Johnson, Cross, Ives and Hillo
"The Use of Electrical Resistance in High Pressure Calibration", Po Wo Bridgroan, R.Sol. 2U, May 1953, Po UOlo
V
"A Versatile Closure for High Pressure Vessels", Johnson, Bowman, Cross, Hill and Ives, Jour. ISA 3^ 7, 1956, pp0 2-3o
Four Terminal Connector
Pressure Vessel 7cm Nut
Heodcr find Coil Assembly
Exiruiion Vinp
J/h* %' °'rini
Figure I Completed Gag
/jotj? The '/qdeep spirajgrooves coi in the. major o.d. of iht mondrc! jhou/a be m the form of a double, or interlocking, 4 ihrea.a± per mck ton fiyura tion.
pRFUMINAKr flftCHINb WORK ON THfe
»STE«riT£ Mandrel (wire lockmj holes noi shown here)
Shorten this loop to decrease coil resistance.
Manoanin Entering N? SO hole in -the mandrel shank
N?80 hole
ih floor of
groove
\
Scrape here io
inert at* coil
resistance F^ure 3 a
#r End of H4«idr*l
Gold-io-go/J Fug Ion Bead
Gold
Leads
Figure 3 b
3ase End of Mandrel
Mfli/v JBcody Dim £n3/o#s
Fic. 4
Break Corner
Slight Radius (opyi .006"-.oto") bright Polish
Re mo vi Scale and grind to sue. No polish Required.
Do not undercui. Leave slight radius'
Distorted Sketch of| High Pressure Header Showing Certfun
Features
Noras I. Break all corners very lightly with paper
Z. A'.B.3. ex pine nee md/ca tes that the O.D. anof ends are best formed uith high spindle speeds and very light cuts. Use carbide lathe tool with large clearance ar^le a. Avoid heating the work.
Figure 6 Fabrication of the Lithographic Limestone Insulating Bushing
c.fi.s. rod
o/o " diagold wire, bead of stiver branny alloy
Step i. brflzing gold wre to rod (see text)
c.k.s.
vbrazing alloy1 Step 3 (See Text)
this diameter a snuo fit ,n the A/?S5 hofe in the bushirg.
M? 70 drill fabrication of the
Electrode (see text)
Fig. 1
'±ocr er)d polished to remove tool marks
this es*d chucked in lathe	/
Step Z. (See text)
'/e x '/r o -ring \ (distortion due to\ being forced into underlie hole)
" gold lead w/re
electrode.
no. ze stranded wtre^ sweated into bole /s m ctectrode. // //
teflon insulation on wire/ slipped forward until flush with end of electrode //
\ lithographic limestone boshing
Details of Packing Socket in Header Main Body
teflon insulation
stranded wire
Abrt: /} flat is milled on the
'/t" diameter- section to which ts attached a 4-termina/ soldering stri/o.
Teflon insulated Wires to electrodes in heodtr
mi/led -flat
Figure 3b
A •torrninal Soldtrihg St tip at upper end of extraction bolt
f/G /O
C.frS.
6CAIS /-/
D/?//l 6 Mass J2 DffP 6M&TA>C£/r T0££Pr// PS T///?£4D.
sjwcvrsIOA/G
F/G //- 4
PA/?r Z C/P.S
PART 3 C/F.S.
PAPT 4 C/?.S.
THE NATIONAL BUREAU OF STANDARDS
Functions and Activities
The functions of the National Bureau of Standards are set forth in the Act of Congress, March 3, 1901, as amended by Congress in Public Law 619, 1950. These include the development and maintenance of the national standards of measurement and the provision of means and methods for making measurements consistent with these standards; the determination of physical constants and properties of materials; the development of methods and instruments for testing materials, devices, and structures; advisory services to Government Agencies on scientific and technical problems; invention and development of devices to serve special needs of the Government; and the development of standard practices, codes, and specifications. The work includes basic and applied research, development, engineering, instrumentation, testing, evaluation, calibration services, and various consultation and information services. A major portion of the Bureau's work is performed for other Government Agencies, particularly the Department of Defense and the Atomic Energy Commission. The scope of activities is suggested by the listing of divisions and sections on the inside of the front cover.
Reports and Publications
The results of the Bureau's work take the form of either actual equipment and devices or published papers and reports. Reports are issued to the sponsoring agency of a particular project or program. Published papers appear either in the Bureau's own series of publications or in the journals of professional and scientific societies. The Bureau itself publishes three monthly periodicals, available from the Government Printing Office: The Journal of Research, which presents complete papers reporting technical investigations; the Technical News Bulletin, which presents summary and preliminary reports on work in progress; and Basic Radio Propagation Predictions, which provides data for determining the best frequencies to use for radio communications throughout the world. There are also five series of nonperiodical publications: The Applied Mathematics Series, Circulars, Handbooks, Building Materials and Structures Reports, and Miscellaneous Publications.
Information on the Bureau's publications can be found in NBS Circular 460, Publications of the National Bureau of Standards ($1.25) and its Supplement ($0.75), available from the Superintendent of Documents, Government Printing Office. Inquiries regarding the Bureau's reports and publications should be addressed to the Office of Scientific Publications, National Bureau of Standards, Washington 25, D. C.
NBS