Thermally stable helically plied cable

A cable, comprising:

• strength material including tensile load bearing elements;
• and bonding material surrounding said load bearing elements;
• said load bearing elements being helically plied at substantially constant helical angle selected to provide bonding material in sufficient quantity that thermal elongation of the cable produced by thermal elongation of said load bearing elements can be opposed by simultaneous increase in cable cross sectional area produced by thermal radial expansion of said bonding material.

A cable, comprising:

• strength material including tensile load bearing elements;
• and bonding material surrounding said load bearing element to form a cable matrix;
• said load bearing elements being plied at substantially constant helical angle selected to provide bonding material in sufficient quantity that thermal elongation of the cable produced by thermal elongation of said load bearing elements can be nulled by simultaneous increase in cable cross sectional area produced by thermal radial expansion of the cable matrix, whereby the cable remains essentially constant in length under varying temperatures.

A method of making a cable, comprising the steps of:

• combining a plurality of tensile load bearing elements which can change in length in response to variation in temperature with thermal radial expansion means for producing change in the cross sectional area of the cable in opposition to and substantially simultaneously with change in length of said load bearing elements;
• and
• controlling the quantity of said radial expansion means present such that overall cable length can be controlled under varying temperatures.

A cable fabricated by the process of combining a plurality of tensile load bearing elements which can change in length in response to variation in temperature with thermal radial expansion means for producing change in the cross sectional area of the cable in opposition to and substantially simultaneously with change in length of said load bearing elements;

• and controlling the quantity of said radial expansion means present such that overall cable length can be controlled under varying temperatures.

A glass fiber cable fabricated by the process of helically winding a plurality of glass fiber rovings to form successive layers of increasing diameter;

• surrounding the filaments of each roving with an uncured elastomeric resin having a curing agent or hardener in contact therewith to form an elastomeric cable matrix;
• and maintaining the helical angle of the initial and successive layers during lay-up at a substantially constant value selected to provide cured elastomeric resin in sufficient quantity that thermal elongation of the cable produced by thermal elongation of the filaments can be nulled by simultaneous increase in cable cross sectional area produced by thermal radial expansion of the cable matrix, whereby the cable remains essentially constant in length under varying temperatures.

A method of controlling thermal elongation of a composite stress member including a load bearing element, which method comprises controlling the cross sectional area of the stress member in accordance with transverse thermal expansion and contraction characteristics thereof such that variation in cross sectional area counteracts the effects of thermal elongation and contraction characteristics of the load bearing element on the length of the stress member, whereby the length of the stress member is controllable under varying temperature conditions.