THE EGG

The Egg is a vibration-attenuating track fastener, appropriate for direct fixation environments - at grade, aerial structures and tunnels. In service in the U.S. since 1983, the Egg owes its excellent acoustical performance and superior maintenance records to its unique design. Vertical forces are cushioned as rubber is placed in shear when the Egg deflects under load from passing trains.

Egg Direct Fixation Fastener
Egg Direct Fixation Fastener

THE EGG: DIRECT FIXATION FASTENER

STANDARD EGG - DIRECT FIXATION FASTENER

of
Egg Direct Fixation Track Fastener Line Drawing
of
Egg Direct Fixation Track Fastener Line Drawing
of
Egg Direct Fixation Track Fastener Line Drawing

The Egg is a vibration-attenuating track fastener, appropriate for direct fixation environments - at grade, aerial structures and tunnels. In service in the U.S. since 1983, the Egg owes its excellent acoustical performance and superior maintenance records to its unique design. Vertical forces are cushioned as rubber is placed in shear when the Egg deflects under load from passing trains. The Egg can now be found in installations across the U.S.

The Egg track fastener is specifically designed to reduce ground-borne vibration, the cause of secondary noise in buildings neighboring transit tracks. The Egg name is derived from its characteristic oval shape.

Egg-type fasteners consist of two metal components, the Top Plate and Frame, bonded together with elastomer. Ductile iron was selected as the best suited for all metal components for reasons of strength, endurance, corrosion resistance and economics. Except under unusual conditions, rubber is the elastomer of choice due to its superior spring performance and enduring life-time characteristics (i.e. dynamic stiffness).

The rail rests on the Top Plate which is oval. Its side surface is angled with respect to the vertical. There is a corresponding angled oval surface built into the outer containment Frame which supports the Top Plate and also houses the anchor bolt holes. The Top Plate is suspended on a belt of elastomer, bonding it to the mating angled surface of the Frame. This allows the Top Plate to “float” and geometry dictates that vertical forces be transmitted largely in shear and only partially in compression. This is perhaps the single most significant feature explaining the unique acoustical effectiveness of the Egg-type design.

Equally important, the geometry also provides “fail-safe” maintenance of track gauge. Thus, the Egg-type design creates the vital combination of lateral integrity and vertical softness. Reacting to overload, or the unlikely event of elastomer failure, the Top Plate sinks further and further into the “nest” provided by the Frame. As it does, lateral stability is not only maintained, but is increased - a huge safety benefit, particularly on curves.

The belt of elastomer separating the two metal components, not only dampens rail forces, but also provides excellent electrical isolation.

Vertical stiffness can be adjusted to customer preference by altering elastomer thickness and/or varying hardness. Typical static stiffnesses are in the range of 50,000 and 75,000 pounds per inch. Stiffness range is approximate. Contact us for more details.

of

Egg Direct Fixation Track Fastener

of

Egg Direct Fixation Track Fastener

Egg Direct Fixation Track Fastener
Egg Direct Fixation Track Fastener

TECHNICAL DETAILS - STANDARD EGG

DIMENSIONS

Body Length     17” 

Body Width     9” 

Width Across Anchor Bolt Flanges     12-15”

Rail Seat Elevation     2 3/4” (70mm)

Rail Base Width     5 1/2” (115# RE Rail)

Cant     Available with no cant and 1:40 cant

 

WEIGHT

Body only     50 lbs 

Gage adjustment clip     0.5 lbs

Pandrol “e” clip     1.7 lbs 

 

Metal Parts     Top Plate, Containment Frame and Gage Adjustment Clip are all ASTM 536, Grade 65-45-12 Ductile Iron Castings

Elastomer     Natural Rubber

Assembly     Metal parts fully bonded together with elastomer

Anchor Bolts     7/8” diameter bolts or studs meeting or exceeding ASTM A-325. Use lock washers in either case. If stud, nut should also meet or exceed A-325

Rail Clips     Pandora “e”-2055 clips

EGG FOR GUARD AND RESTRAINING RAIL APPLICATIONS

of
Egg Direct Fixation Track Fastener Line Drawing
of
Egg Direct Fixation Track Fastener Line Drawing
of
Egg Direct Fixation Track Fastener Line Drawing

These pre-operation views of installed Eggs for Guard and Restraining Rail show their similarity to the standard Egg. The obvious difference is the fact it is bigger and has an increased rail seat dimension to accommodate the guard rail assembly. Vertical stiffness is comparable to that of the standard Egg.

The Egg for Guard and Restraining Rails is in many ways the same as the Egg track fastener for standard track. The obvious difference, of course, is the fact it is bigger and has increased rail seat dimension to accommodate the guard rail assembly.

It will have comparable vertical stiffness.

Essential differences include:

  • Four anchor bolts rather than two
  • Anchor Bolts of 1” diameter
  • Two different Pandora Clips, the e-2055 and 2061

Please note that guard rail block design includes two 1/4” shims. It is recommended to retain this design because there are standard insulators that fill the void created when one or both shims are removed to compensate for expected head wear of the guard/restraining rail.

The Egg fastener is specifically designed to reduce ground-borne vibration, the cause of secondary noise in buildings neighboring transit tracks. The Guard/Restraining Rail Egg contains many of the characteristics and advantages of the standard Egg for normal track.

Egg fasteners consist of two metal components - the Top Plate and containment Frame - bonded together with elastomer. Ductile iron was selected for all metal components because of its strength, endurance, corrosion resistance and economics. Rubber is the elastomer of choice, with corrosion resistance and economics. Rubber is the elastomer of choice, with rare exception, due to its superior spring performance and enduring lifetime characteristics (I.e., dynamic stiffness).

The Guard or Restraining Rail assembly rests on the Top Plate. Its side surface is angled with respect to the vertical. There is a corresponding angled surface built into the outer containment Frame that supports and also houses the anchor bolt holes. The Top Plate is suspended on a belt of elastomer, bonding it to the mating angled surface of the Frame. This allows the Top Plate to “float” and geometry dictates that vertical forces be transmitted largely in shear and only partially in compression. This is perhaps the single most significant feature explaining the unique acoustical effectiveness of the Egg-type design.

Equally important, the geometry also provides “fail-safe” maintenance of track gauge. Thus, the Egg-type design creates the vital combination of lateral integrity and vertical softness. Reacting to overload, or the unlikely event of elastomer failure, the Top Plate sinks further and further into the “nest” provided by the Frame. As it does, lateral stability is not only maintained, but is increased - a huge safety benefit, particularly on curves.

 

TECHNICAL DETAILS - GUARD AND RESTRAINING RAIL

DIMENSIONS

Body Length     23” 

Body Width     10” 

Width Across Anchor Bolt flanges     12”

Rail Seat Elevation     2 3/4” (70mm)

Rail Base Width     10 1/2” (115# RE Rail)

 

WEIGHT

Body only     70 lbs 

Gage adjustment clip     0.5 lbs

Pandrol “e” clip     1.7 lbs 

 

Metal Parts     Top Plate, Containment Frame and Gage Adjustment Clip are all ASTM 536, Grade 65-45-12 Ductile Iron Castings

Elastomer     Natural Rubber

Assembly     Metal parts fully bonded together with elastomer

Anchor Bolts     1” diameter bolts or studs meeting or exceeding ASTM A-325. Use lock washers in either case. If stud, nut should also meet or exceed A-325

Rail Clips     Pandora “e”-2055 clips and "e"-2061 clips

EGG FOR TURNOUT APPLICATIONS

of
Egg Direct Fixation Track Fastener Line Drawing for Turnout
of
Egg Direct Fixation Track Fastener Line Drawing for Turnout
of
Egg Direct Fixation Track Fastener Line Drawing for Turnout

The Egg for Turnouts contains many of the same advantages and characteristics of the standard Egg for normal track.

Egg fasteners consist of two metal components - the Top Plate and containment Frame - bonded together with elastomer. Ductile iron was selected for all metal components because of its strength, endurance, corrosion resistance and economics. Rubber is the elastomer of choice, with corrosion resistance and economics. Rubber is the elastomer of choice, with rare exception, due to its superior spring performance and enduring lifetime characteristics (I.e., dynamic stiffness).

The rails or turnout components rest on the Top Plate. Its side surface is angled with respect to the vertical. There is a corresponding angled surface built into the outer containment Frame that supports and also houses the anchor bolt holes. The Top Plate is suspended on a belt of elastomer, bonding it to the mating angled surface of the Frame. This allows the Top Plate to “float” and geometry dictates that vertical forces be transmitted largely in shear and only partially in compression. This is perhaps the single most significant feature explaining the unique acoustical effectiveness of the Egg-type design.

Equally important, the geometry also provides “fail-safe” maintenance of track gauge. Thus, the Egg-type design creates the vital combination of lateral integrity and vertical softness. Reacting to overload, or the unlikely event of elastomer failure, the Top Plate sinks further and further into the “nest” provided by the Frame. As it does, lateral stability is not only maintained, but is increased - a huge safety benefit, particularly on curves.

The belt of elastomer separating the two metal components not only dampens rail forces, but also provides excellent electrical isolation.

Vertical static stiffness are comparable to the Egg for normal track - in the range of 50,000 and 75,000 pounds per inch. These values are approximate - contact us for more details.

Because of the constantly changing geometry of turnout rails, it is impractical to produce individual Eggs for specific locations. Instead, Turnout Eggs contain a standard pocket in their Top Plate. The turnout manufacturer will supply these plates (according to ATP specifications and drawings) with their special trackwork. Aside from drawings, we can also provide the turnout manufacturer with live samples to confirm and otherwise improve their understanding of the need.

Up to now, the sizes we offer (Type I, II and III) have readily suited the turnouts typically used in transit service. However, if the need arises, we already have designs for larger units (Types IV, V, etc.).

The Frame is supplied with four anchor bolt locations, two on each side of the rail. Openings for anchor bolts are not slotted, therefore do not permit gage adjustment. If this becomes an issue, the design can be altered to include this feature.

Locating anchor bolts at the perimeter of the Frame yields important advantages:

  • When properly torqued, no rail force can reach the anchor bolts.
  • Under abnormal conditions, any force that might finally reach the bolts would first be buffered by the cushioning effect of the elastomer isolating the Top Plate from Frame.

Fasteners are usually mounted directly on the concrete invert, however, if elevation between adjacent fasteners exceeds 1/16”, metal or appropriate plastic shims should be installed which must provide bearing surface under the full fastener “foot-print”.

of
of
Egg Direct Fixation Track Fastener Line Drawing - Turnout
Egg Direct Fixation Track Fastener for Turnout

TECHNICAL DETAILS - TURNOUT APPLICATIONS

DIMENSIONS & WEIGHT

  Type I Type II Type III
Body length 759mm 929mm 1270mm
Body width 395mm 395mm 395mm
Rail seat 70mm 70mm 70mm
"Pocket" length 588mm 730mm 1080mm
"Pocket" width 127mm 127mm 127mm
Weight (fastener only) 45kg 59kg 90kg

 

Metal Parts     Top Plate, Containment Frame are Ductile Iron Castings

Elastomer     Natural Rubber

Assembly     Metal parts fully bonded together with elastomer

Anchor Bolts     1” diameter bolts or studs meeting or exceeding SAE J429 Grade 5. Use lock washers in either case.

Miscellaneous   

  • 5/8” Steel Pocket plate. A-36 (by turnout supplier)
  • 3/16” HDPE Pocket pad
  • 5/8” Grade 5 bolts & nuts to secure Pocket plate
of

Progress Rail offers a full line of trackwork, components and fasteners for heavy haul and transit railways, and is a leading manufacturer of specialty trackwork in North America, the United Kingdom and Australia.

TRACKWORK & FASTENERS

SALES CONTACTS

CLASS 1 RAILROADS

 

Maggie Kukovich

Director - Sales   

EMAIL
TRANSIT, SHORT LINE, CONTRACTORS & INDUSTRIAL

 

Ed Saam

West Director - Sales 
Libertyville, IL
Phone: 224-545-0524         

EMAIL
INTERNATIONAL SALES
 

David May

International Sales Director 
Phone: +1-469-934-8284      

EMAIL
 

Adam Todd

Director, International Business Development
Phone: +44 (0) 7966 337924       

EMAIL

 

Luiz Melo

Business Development Director, LATAM
Phone: +55 (31) 3779-6729
Cell: +55 (11) 97019-0338          

EMAIL
 

Simon Kentfield

PRS UK Sales Director 
Phone: +44 (0) 114 2841 634
Mobile: +44 (0) 7808 897092     

EMAIL

 

Rob de Beer

Infrastructure - Business Development Manager, Australia 
Phone: +61 (0) 408 010 983 

EMAIL
 
SENIOR VICE PRESIDENT - TRACK INFRASTRUCTURE
 

Patrick Jansen

Office Phone: 256-505-6588
Cell Phone: 256-520-6249     

EMAIL
 
VICE PRESIDENT SALES - NORTH AMERICAN TRACK
 

Jeff Harris

Phone: 205-901-9931   

EMAIL