Bolt Cross

Wheel bolt dimensions?

Hi,

I am trying to figure out the diameter of the wheel bolt in a car wheel, a car that breaks with locking it's wheels in these conditions:
- the mass of the car is 1500 kg
- all the weight of the car is shifted on the front wheels
- only the front wheels brake
- the friction coefficient between tire and road is 0.5
- a wheel has 5 bolts that are placed on a circle of 50 mm radius centered in the wheel center
- the total radius of the wheel+tire is 316 mm
- the car produces a torque of 285Nm at 1800 rpm
- the modulus of shearing (I'm not sure if the translation is correct, I'm not a native English speaker) is 100 MPa (the maximum effort that the steel can hold before breaking)

Thank you!

Kind of abusive on the car, maybe?

first lets find the force the road applies to the wheels
normal force is mg
so frictional force is 0.5mg
F = 0.5(1500)(9.81)
F = 7360 N

summing forces about the center of the locked up tire we can determine the force the wheel bolts create to resist the braking load. I'll assume the friction force between the wheel and hub is zero so that all force is carried by the bolts.

7360(316) - Fb(50) = 0
Fb = 46500 N

Assume each bolt is equally loaded on two tires (10 bolts)
each bolt carries
46500/10 = 4650 N

so each bolt cross sectional area is found by dividing by the shear modulus (good job on the english)

A = 4650/100x10^6
A = 4.65x10^-5 m^2

as area for a circle is (pi)r^2
(pi)r^2 = 4.65x10^-5
r = 0.00385 m
so round up to
r = 4 mm
d = 8 mm

This is a minimum and has no factor of safety.

Find Bolt Cross On eBay Below:

SPORTSMAN 80 POUND CROSSBOW ARROWS bolts ARCHERY cross bow hunting pistol new LB
SPORTSMAN 80 POUND CROSSBOW ARROWS bolts ARCHERY cross bow hunting pistol new LB
$29.99
80 lb Pistol Fiberglass Crossbow Archery Cross bow w h 3 Aluminum Bolts hunting
80 lb Pistol Fiberglass Crossbow Archery Cross bow w h 3 Aluminum Bolts hunting
$38.99
Pistol Crossbow With Arrow Holder w 3 Cross Bow Bolts Arrows 80 LB NEW
Pistol Crossbow With Arrow Holder w 3 Cross Bow Bolts Arrows 80 LB NEW
$34.95
20 PCS 15 150 180 lb Aluminum Hunting Crossbow Bow Bolts Arrows Scope Cross Bow
20 PCS 15 150 180 lb Aluminum Hunting Crossbow Bow Bolts Arrows Scope Cross Bow
$32.48
120LB DRAW CROSSBOW +2 BOLTS ADJUSTABLE CROSS BOW + 2 ARROWS LAST ONE HUNTING
120LB DRAW CROSSBOW +2 BOLTS ADJUSTABLE CROSS BOW + 2 ARROWS LAST ONE HUNTING
$87.00
Crossbow w 5 Arrows Bolts Cross Bow 50 lb Pistol Hand Held Gun Archery Mini NEW
Crossbow w 5 Arrows Bolts Cross Bow 50 lb Pistol Hand Held Gun Archery Mini NEW
$44.13
NEW Mission MXB 400 Cross Bow With Pro Package W Scope Quiver Bolts Case Rope
NEW Mission MXB 400 Cross Bow With Pro Package W Scope Quiver Bolts Case Rope
$1,599.00
BladesUSA Eagle2 D Crossbow Bolts 14 Inch Aluminum Dart For 150 Pound S Cross
BladesUSA Eagle2 D Crossbow Bolts 14 Inch Aluminum Dart For 150 Pound S Cross
$13.80
BladesUSA Eagle2 D Crossbow Bolts 14 Inch Aluminum Dart For 150 Pound S Cross
BladesUSA Eagle2 D Crossbow Bolts 14 Inch Aluminum Dart For 150 Pound S Cross
$13.62
Cross Bow Bolts 12 count
Cross Bow Bolts 12 count
$10.00
5 PCS 15 150 180 lb Aluminum Hunting Crossbow Bow Bolts Arrows Scope Cross Bow
5 PCS 15 150 180 lb Aluminum Hunting Crossbow Bow Bolts Arrows Scope Cross Bow
$8.48
Self Cocking ALUMINUM PISTOL SYSTEM 80 lb CROSSBOW CROSS BOW W 3 BOLTS
Self Cocking ALUMINUM PISTOL SYSTEM 80 lb CROSSBOW CROSS BOW W 3 BOLTS
$49.00
180LB CAMOUFLAGE HUNTING CROSSBOW + 4x20 SCOPE + 14 BOLTS camo cross bow 180 lb
180LB CAMOUFLAGE HUNTING CROSSBOW + 4x20 SCOPE + 14 BOLTS camo cross bow 180 lb
$139.89


Recently Purchased Bolt Cross:


pistol crossbow with arrow holder w3 cross bow bolts arrows 80 lb new, bladesusa eagle2d crossbow bolts 14inch aluminum dart for 150pound s cross, 120lb draw crossbow 2 bolts adjustable cross bow 2 arrows last one hunting, 80 lb pistol fiberglass crossbow archery cross bow wh 3 aluminum bolts hunting, cross bow bolts 12 count, crossbow w 5 arrows bolts cross bow 50 lb pistol hand held gun archery mini new, self cocking aluminum pistol system 80 lb crossbow cross bow w3 bolts, new mission mxb 400 cross bow with pro package w scope quiver bolts case rope , 20 pcs 15 150 180 lb aluminum hunting crossbow bow bolts arrows scope cross bow, 5 pcs 15 150 180 lb aluminum hunting crossbow bow bolts arrows scope cross bow, sportsman 80 pound crossbow arrows bolts archery cross bow hunting pistol new lb, 180lb camouflage hunting crossbow 4x20 scope 14 bolts camo cross bow 180 lb



Comments are closed.