U-bolt torquing method
AssigneeConsolidated Metal Products, Inc.
InventorFreddie Madden
Life of this patent
Estimating the term…
Abstract
A method of determining the optimum torque for securing a U-bolt assembly calculated according to the formula T=UL.multidot.d.multidot.K.multidot.LF, where T is the optimum torque, UL is a calculated value for the ultimate tensile load of one U-bolt leg, d is the diameter of the threaded end of one U-bolt leg, K is a torque coefficient of friction associated with the U-bolt assembly, and LF is a chosen load safety factor. A tool used in securing the U-bolt assembly includes at least one surface having torquing indicia located thereon and a radius for testing the bend radius on the U-bolt. The torquing indicia includes U-bolt assembly designation data and a corresponding optimum torque value.
Claims4
A method of installing a U-bolt assembly, comprising the steps of:
- providing a U-bolt assembly comprising a U-bolt made of a material having an ultimate tensile strength, the U-bolt having two bends and two end-threaded legs, each bend having a radius and each leg having a diameter and a cross-sectional area, and a nut for being threaded on the end of each leg of the U-bolt;
- calculating a predicted reduction in strength of the U-bolt as a result of one of the bends in the U-bolt according to the formula B=[(R/D)X]+C, B being said predicted reduction in strength, R being the bend radius of one of the bends in the U-bolt, D being the diameter of one of the legs of the U-bolt, X being a regression coefficient and C being a regression constant;
- calculating an ultimate tensile load of one of the legs of the U-bolt according to the formula UL=CA.multidot.TN.multidot.B, UL being said ultimate tensile load, CA being the cross sectional area of one of the legs of the U-bolt, TN being the ultimate tensile strength of the U-bolt material and B being said predicted reduction in strength;
- calculating the optimum torque used to tighten the nut on each of the legs of the U-bolt according to the formula T=UL.multidot.d.multidot.K.multidot.LF, T being said optimum torque, UL being said ultimate tensile load, d being the diameter of the threaded end of one leg, K being a torque coefficient of friction associated with the U-bolt assembly, and LF being a chosen load safety factor;
- and
- threading one nut on the end of each of the legs of the U-bolt and applying said optimum torque to each nut.
Dependencies are inferred from the claim text.