A&K has numerous frog designs available in either Bolted Rigid or Manganese Cast Steel construction. Your A&K Rail and Track Specialists will assist you in selecting the proper design and construction to meet your traffic specifications. Frogs can be furnished to A.R.E.A. and A.M.C. specifications, or modifications can be made for your particular trackage.
Frog Diagram


How To Order Frogs

When ordering standard frogs, please specify the following:
1. Frog Design
2. Frog number or angle
3. Weight and section of rail
4. Overall length
(All measurements should be taken on the gauge lines).

How To Determine The Number of a Frog
The frog number is the ratio of its length (measured on center line of frog) to its width, or the number of inches in length necessary for it to spread one inch in width. For example, a No. 3 frog spreads 1 in 3, a No. 5 spreads 1 in 5, a No. 8 spreads 1 in 8, etc.

To determine the number of a straight frog, measure across the frog point at place (A) where the distance between the gauge lines is an even number of inches: measure again where the distance (B) is an inch greater than at (A); the number of inches (C) between the two measured sections (A and B) is the number of the frog as shown above.

To the left is a table of frog numbers and their corresponding angles.
Frog No. Frog Angle
5 11 -25'-16"
6 9 -31'-38"
8 7 -09'-10"
9 6 -21'-35"
10 5 -43'-29"
11 5-12'-18"
12 4 -46'-19"
14 4 -05'-27"


Solid Manganese Steel Self Gaurded Frog

Solid Manganese Steel Self Gaurded Frog
Solid Manganese Steel Self Gaurded Frog


A&K Solid Manganese Frogs

These one piece Solid Manganese Cast Steel Frogs are recommended by A&K's Rail and Track Specialists for location subject to heavy traffic and moderate speeds.
Frog Lengths
Group A Rails
Frog
No. 		Total
Length 		Toe
Length 		Heel
Length 		Var.
Radius
4 5'-1" 15" 3'-10" 23"
5 5'-6' 18" 4'-0" 3'-2"
6 6'-0" 22" 4'-2" 4'-10"
7" 6'-10" 2'-1" 4'-9" 6'-9
8 7'-10" 2'-5" 5'-5" 8'-11"
9 8'-10" 2'-9" 6'-1" 11'-5"
10 9'-9" 3'-0" 6'-9" 14'-2"
Group B Rails
Total
Length 		Toe
Length 		Heel
Length 		Var.
Radius
5'-1" 15" 3'-10" 23"
5'-5' 17" 4'-0" 3'-2"
5'-11" 21" 4'-2" 4'-10"
6'-7" 2'-0" 4'-7" 6'-8"
7'-7" 2'-4" 5'-3" 8'-10"
8'-5" 2'-7" 5'-10" 11'-3"
9'-4" 2'-10" 6'-6" 14'-0"
Group C Rails
Frog
No. 		Total
Length 		Toe
Length 		Heel
Length 		Var.
Radius
4 5'-1" 15" 3'-10" 23"
5 5'-5" 17" 4'-0" 3'-2"
6 5'-10" 20" 4'-2" 4'-9"
7 6'-3" 23" 4'-4" 6'-8"
8 7'-3" 2'-3" 5'-0" 8'-9"
9 8'-1" 2'-6" 5'-7" 11'-2"
10 8'-11" 2'-9" 6'-2" 13'-11"
Group D Rails
Total
Length 		Toe
Length 		Heel
Length 		Var.
Radius
5'-1" 15" 3'-10" 23"
5'-5' 17" 4'-0" 3'-2"
5'-10" 20" 4'-2" 4'-9"
6'-2" 22" 4'-4" 6'-6"
6'-11" 2'-1" 4'-10" 8'-7"
7'-9" 2'-4" 5'-5" 11'-0"
8'-7" 2'-7" 6'-0" 13'-8"
Group E Rails
Frog
No. 		Total
Length 		Toe
Length 		Heel
Length 		Var.
Radius
4 5'-11" 2'-1" 3'-10" 23"
5 6'-5" 2'-1" 4'-4" 3'-3"
6 7'-4" 2'-11" 4'-5" 5'-0"
7 8'-1 1/2" 2'-11" 5'-2 1/2" 7'-0"
8 8'-11" 2'-11" 6'-0" 9'-2"
9 9'-9" 2'-11" 6'-10" 11'-6"
10 11'-4 1/2" 3'-9" 7'-7 1/2" 4'-8"


Quantity of Hook Twin Plates
Frog
No. 		Type 1 Rails Type 2 Rails Type 3 Rails
Mark L23 L27 H23 H27 H31 H35 LR23 LR27 LR31 L23 L27 H23 H27 H31 H35 LR23 LR27 LR31 L23 L27 H23 H27 H31 H35 LR23 LR27 LR31
5 4 2 4 2 0 2 0 2 0 4 2 4 2 0 2 0 2 0 4 2 4 2 0 2 0 2 0
6 4 2 4 2 0 2 0 2 0 4 2 4 2 0 2 0 2 2 4 2 4 2 2 2 0 2 2
7 4 4 2 4 0 2 2 2 0 4 4 2 4 0 2 2 2 2 4 2 4 4 2 2 0 2 2
8 6 2 2 4 2 0 2 4 0 6 4 4 4 2 0 0 4 2 4 4 4 4 2 2 0 4 2
9 8 2 2 4 2 0 2 4 0 6 4 4 6 0 0 2 4 2 4 4 6 6 2 0 0 4 2
10 8 2 4 6 0 0 4 4 0 6 4 6 6 2 0 2 4 2 6 4 6 6 2 0 2 4 2


A&K Bolted Rigid Frogs

This type of frog is used in yard and industrial tracks where the traffic is light on both sides of the frog.

Data for A.R.E.A. Plan No. 323-59 Frogs
Frog Number 4 5 6 7 8 9 10 11 12
A.R.E.A. Plan
Reference 		322-59 322-59 322-59 323-59 323-59 323-59 324-59 324-59 324-59
Angle 14º15' 11º25'16" 9º31'38" 8º10'16" 7º09'10" 6º21'35" 5º43'29" 5º12'18" 4º46'19"
Frog Length 8'-0" 9'-0" 10'-0" 12'-0" 13'-0" 16'-0" 16'-6" 18'-8 1/2" 20'-4"
Toe Length 3'-4" 3'-6 1/2" 3'-9" 4'-8 1/2" 5'-1" 6'-4 1/2" 6'-5" 7'-0" 7'-9 1/2"
Heel Length 4'-8" 5'-5 1/2" 6'-3" 7'-3 1/2" 7'-11" 9'-7 1/2" 10'-1" 11'-8 1/2" 12'-6 1/2"


Rail Bound Manganese Steel Frogs for rails 112 lb. and heavier
This type of frog is used for heavy or high speed mainline service where the traffic is approximately equal on both sides of the frog.


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