Welcome To

An Introduction to Hex Head Cap Screw Products

© Brighton-Best International, Inc.

Brighton Best was founded in 1925

With 20 US locations, BBI is the largest master distributor of commercial fasteners

Stocking over 80,000 SKUs, BBI offers the most comprehensive line of fasteners in the Industry

Brighton Best International

Learning Objectives

Identify the Grades

Understand the Grade Characteristics

Name the Available Finishes

What Makes L9 Special

Who Uses Hex Caps?

K n o w n b y t w o n a m e s , h e x h e a d c a p

s c r e w s o r s i m p l y , h e x c a p s c r e w s , h e x

h e a d c a p s c r e w p r o d u c t s a r e a l e a d i n g

l i n e f o r i n d u s t r i a l s u p p l i e r s a r o u n d

t h e w o r l d . Av a i l a b l e i n m u l t i p l e

g r a d e s a n d f i n i s h e s b a s e d o n t h e

a p p l i c a t i o n , o u r H e x C a p s a r e s o u r c e d

b o t h d o m e s t i c a l l y a n d i m p o r t e d .

Hex Cap Products

Primary Markets

Industrial

Automotive

Electrical

Power/Energy

Military

Rail

Municipal

Hex Head Cap Screws vs. Hex Bolts

A cap screw has a flat washer face underneath the head

Washer Face

• Hex bolts do not

Cap screws are chamfered on the end easing its insertion into a tapped hole.

Tightening

• Hex bolts require a nut

Cap screws fall under ASTM J429Specs

• Hex bolts fall under ASTM A307

Cap screws have tighter tolerances than Hex boltsTolerances

What is on a Buyer’s Mind?

What Grade is Required? Hex cap screws come in 3 grades based on

strength.

What finish do they need? It is important to know whether the end

user needs them plain or plated

Domestic or Imported? Some applications require domestic

material, while others do not. Whether domestic or import, all hex caps fall under the same specifications and are made under IFI standards.

Is it inch or metric? Knowing whether the need is inch or metric

is critical to servicing the buyer’s needs.

• An assembly operation not requiring excessive strength

• Electrical repair• General Hardware

Applications

Applications

HeadMarking

Specification Fastener Discription

Material Nominal Size Range (in.)

Proof Load (psi)

Yield Strength Min.

(psi)

Tensile Strength Min.

(psi)

No Head Mark ASTM SAE J429

Bolts, Screws Low or Medium Carbon Steel

¼ thru ¾¾ - 1 ½

55,00033,000

57,00036,000

74,00060,000

Plain, Zinc CR+3

Grade 2

HeadMarking

Specification Fastener Discription

Material Nominal Size Range (in.)

Proof Load (psi)

Yield Strength Min.

(psi)

Tensile Strength Min.

(psi)

Three Radial Lines

ASTM SAEJ429

Bolts, Screws Low or Medium Carbon Steel

¼ thru 11 – 1 1/21 ½ - 3

85,00074,00055,000

92,00081,00058,000

120,000105,00090,000

Grade 5

M A N U F A C T U R E D F R O M M E D I U M C A R B O N S T E E L , M E T R I C H E X H E A D S M A D E T O C L A S S 8 . 8 A R E S I M I L A R T O A G R A D E 5 I N S T R E N G T H .

Nominal Size Range (mm)

Proof Load (Mpa)

Min. Yield Strength (MPa)

Min. Tensile Strength (MPa)

All sizes below 16mm

580 640 800

16mm – 72mm 600 660 830

Plain, Zinc-Blue

Metric 8.8

HeadMarking

Specification Fastener Discription

Material Nominal Size Range (in.)

Proof Load (psi)

Yield Strength Min.

(psi)

Tensile Strength Min.

(psi)

Six Radial Lines ASTM SAE J429

Bolts, Screws Medium Carbon,

Quenched and Tempered

¼ - 1 1/2 120,000 130,000 150,000

P R O D U C E D U S I N G M E D I U M C A R B O N S T E E L , T H E G R A D E 8 H E X C A P S C R E W S A R E U S E D I N A U T O M O T I V E A N D O T H E R H I G H - S T R E S S E N V I R O N M E N T S . A V A I L A B L E I N P L A I N A N D Z I N C - Y E L L O W F I N I S H E S , B B I S U P P L I E S G R A D E 8 P R O D U C T S F R O M T H E U . S . A N D T A I W A N . Plain, Zinc-

Yellow CR+3

Grade 8

P R O D U C E D U S I N G M E D I U M C A R B O N S T E E L , T H E C L A S S 1 0 . 9 M E T R I C H E X C A P S C R E W S , A R E C O M P A R A B L E T O A G R A D E 8 I N S T R E N G T H . A V A I L A B L E I N P L A I N A N D Z I N C - B L U E F I N I S H F O R C O R R O S I O N R E S I S T A N C E .

Nominal Size Range (mm)

Proof Load (Mpa)

Min. Yield Strength (MPa)

Min. Tensile Strength (MPa)

5mm – 100mm 830 940 1040

Plain, Zinc-Blue

Metric 10.9

L 9 H e x C a p S c r e w

H i g h e r H e a d a l l o w s f o r i n c r e a s e d w r e n c h a b i l i t y

1 8 0 , 0 0 0 p s i m i n T e n s i l e S t r e n g t h

L 9 H e x N u t

L a r g e r t h a n s t a n d a r d n u t w a l l s

L 9 P r e v a i l i n g T o r q u e H e x N u t

F o r a s s e m b l i e s s u b j e c t t o v i b r a t i o n

L 9 S A E o r U S S F l a t W a s h e r s

H R C 4 0 - 4 5 a n d p l a t e d f i n i s h e s t h a t a s s i s t i n t o r q u e , w i t h s i n g l e c h a m f e r i n s i d e d i a m e t e r .

Made in the USA

The L9 Fastening System

I nch P ro duc t s Met r ic P ro duc t

18 -8 He x Ca p s A 2 He x Ca p s

(D i n 931 , 933 )

316 He x Ca ps

18 -8 F u l l Th r e a d e d He x Ca p s

Stainless Hex Cap Products

Series Property Marking Diameter Range Tensile Strength ksi

18-8 F593C

F593D

¼ - 5/8

¾ - 1 ½

100 - 150

85 - 140

316 F593G

F593H

¼ - 5/8

¾ - 1 ½

100 – 150

85 - 140

A2 (DIN 931, 933) A2-70 ALL 700 MPa

Diameter and Thread Comparison

Course and Fine Threaded Fasteners

The thread length is the number of threads per inch. So for ¼-20, you have a 1/4’ diameter fastener with 20 threads per inch.

Course threaded fasteners have fewer threads per inch than fine threaded products.

COARSE FINE

M6-1.00 M6-0.75

M8-1.25 M8-1.00

M10-1.50 M10-1.25

M12-1.75 M12-1.50

M14-2.00 M14-1.50

M16-2.00 M16-1.50

M20-2.50 M20-1.50

M22-2.50 M22-1.50

M24-3.00 M24-2.00

M27-3.00 M27-2.00

M30-3.50 M30-2.00

M36-4.00 M36-2.00

M42-4.50 M42-2.00

M48-5.00 M48-2.00

COARSE FINE

¼-20 ¼-28

5/16-18 5/16-24

3/8-16 3/8-24

7/16-14 7/16-20

½-13 ½-20

9/16-12 9/16-18

5/8-11 5/8-18

¾-10 ¾-16

7/8-9 7/8-14

1-8 1-14

1 1/8-7 1 1/8-12

1 ¼-7 1 ¼-12

1 3/8-6 1 3/8-12

1 ½-6 1 ½-12

Tensile Strength

Comparison

Tensile strength is the maximum stress level that a fastener can withstand before it exhibits structural loss. That is to say the maximum amount of pressure a fastener can be pulled before it breaks.

Head and Wrench Size

Want to know what wrench size goes with each diameter?

Bolt Diameter Wrench Size

#6 ¼

#8 ¼

#10 5/16

#12 5/16

¼ 7/16 or 3/8

5/16 ½

3/8 9/16

7/16 5/8

½ ¾

9/16 13/16

5/8 15/16

¾ 1 1/8

7/8 1 5/16

1 1 ½

1 1/8 1 11/16

1 ¼ 1 7/8

Grade 5 Hex Cap Possibilities

Finding Hex Caps in BBIsWeb-Ordering System

A. How many inch grades of hex cap screws does BBI carry?

B. How many families of Grade 5 hex cap screws does BBI offer?

C. What ASTM specification does hex cap screws fall under?

D.Are hex cap screws available imported and domestic?

E. Are Grade 8 hex cap screws stronger than Grade 5 hex cap screws?

F. What is the head marking for a L9 hex cap screws?

G. What finishes are available for Grade 2 hex cap screws?

Questions

A. Three, Grades 2, 5 and 8

B. 8

C. J429

D.Yes

E. Yes, their tensile strength is 92k min vs. 120k min, 120k

max vs. 150k max

F. L9

G. Plain and zinc-plated

Answers

On beha l f o f t he en t i r e B r i gh ton Bes t f am i l y, we wan t t o thank you f o r t ak ing a f ew m inu tes

t o l ea rn more abou t who we a re , ou r

va lue - sys tem and ou r p roduc t s .

Eve ry t ime you p l a ce an o rde r w i th us , you a re g i v i ng us an oppo r tun i ty t o p rove ou r

commi tment t o se rv ing you .

Thank you f o r the oppo r tun i ty and p r i v i l ege o f work ing w i th you .

WrapUp