15 CRR-NY 51.4NY-CRR

15 CRR-NY 51.4
15 CRR-NY 51.4
51.4 Standards for retreaded tires.
(a) No tire shall be retreaded (recapped), distributed, offered for sale or sold in this State for use on the public highways of this State unless such retreading is done in conformance with the following standards.
(b) Definitions.
For the purposes of this section the following terms shall have the following meaning:
(1) Full-treading.
The worn tread rubber is rasped or buffed off the top of the tread and over the shoulders as far as the new rubber is to extend.
(2) Top treading.
In top treading only the top of the old tread is rasped or buffed off. All the new rubber is applied just to the top of the tread.
(3) Undertread.
Rubber between the base of the anti-skid design and buffed tire body.
(4) Skid-depth.
The distance measured near the center-line of the tire from the base of the anti-skid design to the top of the tread.
(5) Natural rubber.
Natural rubber shall include all forms and types of tree, vine, or shrub rubber.
(6) Synthetic rubber.
Two types of synthetic rubber are commonly used in retreading. These are usually indentified as SBR synthetic rubber and BR synthetic rubber. The former is a butadine-styrene rubber and the latter a type called stereo synthetic rubber made from butadine and sometimes also called polybutadine or PBD.
(7) Cold rubber.
Cold rubber is a type of synthetic rubber polymerized at approximately 41 degrees Fahrenheit, as distinguished from hot rubber polymerized at approximately 122 degrees Fahrenheit.
(8) Reclaimed rubber.
Reclaimed rubber is any rubber derived from the processing or treatment of vulcanized rubber or cured scrap rubber.
(c) Material requirements.
(1) The purpose and intent of this section is to establish within reasonable limits general guides for the selection of tread rubber and other materials which will give the ultimate user the highest possible tread wear under normal operating conditions. Therefore, the minimum quality tread rubber used must be of a grade and quality level which is considered as a manufacturer's highest quality exclusive of premium grades designed for high abrasion resistance.
(2) Labelling.
Tread rubber shall show whether it is natural rubber, cold rubber, or synthetic rubber and will also show rate of cure, such as, fast cure or regular cure on each box.
(3) Standard dimensional tolerances.
For the purpose of measuring the width and thickness of tread rubber, a cut should be made straight across the full width of the tread rubber with a sharp knife. The cut should be made not less than three or more than six feet from the outside end of the roll and also it must be away from the point where the weight of the roll or other pressure may have distorted the dimensions.
(i) Thickness includes cushion, if used, but does not include backing.
(a) For nominal gauges of 13/32 inch and less, a tolerance of minus 0/64 inch and plus 3/64 inch is established. This excludes tread rubbers containing traction producing additives.
(b) For nominal gauges of 14/32 inch and up to and including 18/32 inch, a tolerance of minus 1/64 inch and plus 2/64 inch is established.
(c) For nominal gauges of 20/32 inch and up to and including 24/32 inch, a tolerance of minus 1/64 inch and plus 3/64 inch is established.
(d) For nominal gauges of 26/32 inch and up to and including 32/32 inch, a tolerance of minus 2/64 inch and plus 4/64 inch is established.
(ii) Width.
(a) For tread rubber sizes with a base width of six inches and less, a tolerance of plus 1/16 inch and minus ⅛ inch is established.
(b) For tread rubber sizes with a base width of more than six inches, but not more than 12 inches, a tolerance of plus ⅛ inch and minus ⅛ inch is established.
(c) For tread rubber with a base width of over 12 inches, a tolerance of plus ¼ inch and minus ¼ inch is established.
(iii) Bevel or wing width.
(a) Wing width control.
(1) For “wing-size” tread rubber with a base width of six inches or less, the center line of the crown should coincide with the center line of the base within 1/16 inch.
(2) For “wing-size” tread rubber with a base width of six inches but not over 12 inches, the center line of the crown should coincide with the center line of the base within ⅛ inch.
(3) For “wing-size” tread rubber with a base of over 12 inches, the center line of the crown should coincide with the center line of the base within ¼ inch.
(b) Bevel width. For all “Bevel” tread rubber, the center line of the crown should coincide with the center line of the base within 1/16 inch.
(iv) Wing edge thickness. A maximum edge thickness of 7/64 inch is established.
(a) The thickness should be measured by using calipers with graduations in 64th's of an inch.
(b) The calipers should have the jaws opened at 7/64 inch and the wing edge inserted. If the edge is admissible, it meets the required dimension.
(v) Center line position. The center point of the center line mark should be within 1/16 inch of the actual measured center of the crown of the tread rubber when the crown width is 10 inches or less, and it should be within ⅛ inch of the measured center of the crown when the crown width is over 10 inches.
(4) Padding stock.
The padding stock shall be suitable for filling in worn (low) spots under tread rubber and made from a fast cure compound compatible with natural and synthetic rubber.
(5) Filler strip stock.
The filler strip stock shall be a minimum of 4/32 inch thickness at the center line. This stock shall be suitable for filling around the complete circumference of the tire being retreaded to insure the proper undertread, and shall be made from a fast cure compound compatible with natural and synthetic materials.
(6) Cement.
Vulcanizing cement used for adhesion of conventional tread rubber to the buffed tire shall be made with natural rubber and the necessary cement must be capable of being vulcanized and suitable for the use intended. Special cements made for the adhesion of particular compounds such as those used in extrusion application of tread stock must be specifically compounded to meet all necessary requirements as an adhesive and bonding agent—both before and after cure. It is not required that this type of cement be made of any specific rubber type, or that the solvent be a petroleum distillate alone.
(7) Rubber solvent.
The rubber solvent shall consist entirely of petroleum distillate, and shall be water-clear, free from foreign material, acid, water, or antiknock materials. When subjected to distillation in accordance with an applicable method, the solvent shall show an initial boiling point (I.B.P.) of 100 degrees to 140 degrees Fahrenheit, and an end point (E.P.) of 250 degrees to 300 degrees Fahrenheit, with no oily residue.
(8) Age limits and storing conditions for repair materials and tread rubber of all types, including strip stock for extrusion machines.
Tread rubber for pneumatic tires of all types, repair materials and unvulcanized accessories should be stored in a dry place, protected from the elements and direct exposure to sunlight and the temperature of the storage area should be kept below 80 degrees Fahrenheit. Under these conditions, tread rubber and repair materials should be expected to remain in a satisfactory condition for six months after date of receipt from the manufacturer. Colder storage conditions extend the shelf life, without harm to the product. Warmer storage conditions shorten the shelf life. Tread rubber and repair materials exposed to temperatures of 80 degrees to 95 degrees Fahrenheit, can be expected to have their shelf life reduced 25 percent and if stored at temperatures of 95 degrees to 110 degrees Fahrenheit, a reduction of 50 percent or more can be expected. Tread rubber and repair materials will not tolerate temperatures of over 110 degrees for more than a very short time without danger of vulcanization. If the tread rubber and repair materials are exposed to temperatures which cause freezing or hardening of the stock (which can occur at temperatures below 40 degrees Fahrenheit) the stock must be carefully restored to its original condition by warming it at a temperature between 70 degrees and 90 degrees Fahrenheit. Tread rubber, repair materials and all unvulcanized accessories are made to meet exacting standards and to perform under existing field conditions, and at the same time to be as satisfactory as possible for shelf aging. Because these materials are shipped to widely varied climates and are subjected to all types of storage the possibility of deterioration is always present. The storage period and conditions specified reflect general industry experience. Violation of these specifications may be reflected as an appreciable deterioration of a percentage of the material affected and does not mean that such material is unusable or subject to failure because of age.
(d) Inspection of tire.
(1) Careful inspections shall be made by a skilled operator, and shall include placing the tire on a mechanical spreader under adequate lighting, distorting the natural contour of the tire sufficiently to expose any evidence of ply separation, impact breaks, or other defects without damaging the bead.
(2) Inspection standards.
Tires that have a known separation between the plies shall not be retreaded, and should be destroyed. No tires to be accepted for retreading may contain any of the following weaknesses or injuries.
(i) Ply separation.
(ii) Ply fabric injury in the bead area; also chafed fabric injuries in tubeless tires.
(iii) Broken, damaged, bent, or exposed bead wires.
(iv) Flex breaks.
(v) Loose cords on the inner ply or evidence of having been run underinflated or overloaded.
(vi) Tread separation, other than that which can be removed in the buffing operation.
(vii) More than surface weather checking.
(viii) Generally weakened condition due to age, moisture, and/or exposure.
(ix) Tubeless tires with porous liners or defective splices in liners.
(x) Any passenger motor vehicle casing containing an impact, bruise, or “X” type break, cut or any other type of casing injury requiring what is commonly known as a section repair.
(xi) Wear extending to the fabric.
(xii) Any cracks, such as radial or groove cracks which extend to the fabric or which cannot be removed without exposing the fabric.
(xiii) Any passenger motor vehicle tire previously repaired, except a satisfactory nail hole repair.
(xiv) Any open liner splice which shows exposed fabric.
(xv) Any two-ply tire which is so worn that the cords of the top or outside ply will be damaged during the buffing operation.
(3) Moisture.
All tires to be processed shall be thoroughly dry and all cords free of moisture.
(4) Nail holes.
All nail holes must be thoroughly cleaned and inspected for extent of casing injury. If casing is punctured only and does not require a full section repair or reinforcement, the nail hole may be filled and treated in the conventional manner so as to provide a sound tire body for processing.
(e) Processing.
(1) Buffing.
The tire shall be uniformly buffed using a matrix template or other satisfactory system of measurement to insure proper matching of buffed crown contour with matrix tread contour and overall diameter. The buffed surface should be of a smooth texture and free from moisture, loose cords and foreign material which would affect adhesion properties between casing and tread rubber. Proper buffing dimensions for each matrix must be posted in the buffing room. These should include:
(i) Matrix identification.
(ii) Buffed tread width.
(iii) Buffed crown contour.
(iv) Overall buffed width.
(v) Overall buffed diameter.
(vi) Bead to bead dimensions where specified by matrix manufacturer.
(vii) Overall diameter and cross-sectional data.
with minimum and maximum measurements.
(2) Cementing.
The cementing process should begin within a reasonable time after the buffing operation is completed to avoid the hazards of an oxidized surface. Each container of cement shall be tested for freshness. If solvent is used as a thinner, this too must be tested for presence of oil or water. Tires to be cemented must be free from moisture and foreign material such as buffing dust, dirt, loose cords, etc. Extreme caution must be taken on air lines used to blow dust from the surface of a tire. Efficient moisture traps must be located as close as possible to the air release valve to prevent moisture from being blown onto the surface of the tread area.
(3) Building.
(i) Full tread. Shall be made with wing-type tread rubber, and shall extend over shoulders.
(ii) Top tread. Shall extend only across the tread area, thus conforming with that tread known commercially as a top tread.
(iii) If the breaker is exposed on any portion of the buffed area, it shall be covered with a suitable protective padding stock or cushion gum before applying the tread rubber.
(iv) Splicing. Tread rubber shall be skived or butted at one end. The tread rubber shall then be applied to the tire and shall be centered over the entire circumference. After the backing is removed, the cushion surface shall not be handled or touched. The other end of the tread rubber shall then be skived or butted to match the end previously skived or butted.
(v) Stitching. Stitching or rolling of tread rubber shall then be accomplished starting at the center and working to the edges so that air pockets will be eliminated. Wrinkles at edges of tread (on wing dies) shall be thoroughly stitched. Edges of top tread rubber shall be tight. All air pockets must be eliminated. The use of mechanical stitchers or tread builders is recommended for efficiency. However, their operation must be checked for extrusion or thinning out of original tread rubber die size which causes thin spots, open slices, tread cracking, etc.
(vi) Extrusion. Application of strip stock as used in extrusion machines shall follow directions of equipment manufacturer.
(4) Curing.
(i) shall be started as soon as practicable after the building operation has been completed. Curing temperatures, time, and pressure shall accurately follow mold and rubber manufacturers directions. A correlation between the curing characteristics of the tread rubber and heating characteristics of the mold is necessary. Extra curing time must be taken into consideration when using filling strips or padding stock and the rubber cured accordingly.
(ii) Curing equipment. Molds and/or matrices shall be so designed and installed with sufficient heat so that:
(a) Temperatures to within plus or minus 5 degrees Fahrenheit tolerance will be maintained according to mold and/or tread rubber manufacturer's recommendation;
(b) Necessary precaution should be taken to provide uniform drainage of condensate from the molds, if steam;
(c) Necessary precautions should be taken to obtain uninterrupted flow of current to molds, if electric;
(d) Proper sizes of curing tubes and rims shall be inserted in accordance with matrix manufacturers specifications and in accordance with side wall thickness of tire.
(iii) Molds shall be equipped with instruments in good condition, located to indicate mold temperature accurately. They shall be so designed as to cure retreaded tires without damage or distortion.
(iv) Air pressure recommended by equipment manufacturer must be maintained and controlled through accurate gauges as close to each outlet as possible in order to insure proper reading.
(5) Final finishing.
After curing, the retreader shall make a final examination of the tire, checking inside to insure that nail holes and loose cords have been properly treated and that the tire is not buckled. The outside of the tire shall be checked to insure adequate moldings and curing. The tread shall be straight and not porous. Each tire shall be trimmed cleaned and/or painted.
(6) Tread thickness.
The tread rubber used shall be of such thickness as to provide the following amount of undertread to adequately meet requirements. Undertread thickness should be gauged after the tire has been retreaded and does not necessarily reflect tread rubber thickness.
Tire sizeUnder treadSkid depth
Passenger: Conventional Designs
Less than 7.00″ cross section9/329/32
7.00″ cross section and larger2/3210/32
Passenger: Mud and Snow Designs
Less than 7.00″ cross section2/3212/32
7.00″ cross section and larger2/3214/32
Commercial Truck Tires
(Less than 20″ bead diameter)
Less than 7.50″ cross section3/32*
7.50″ cross section and larger4/32*
Large Truck Tires
(20″ bead diameter and larger)
Less than 9.00″ cross section4/32*
9.00″ cross section and larger5/32*
Equal to that of new 100 level tire of same size and type–minus tolerance 2/32″.
(f) Control instruments.
The effective use of time clocks, heat gauges, mold and/or matrix temperature gauges is required for the control of heat, time and air pressure. These gauges should be calibrated regularly to insure their accuracy.
(g) Warranty.
In order that the consumer may know that the retreaded tire purchased actually complies with the specifications set forth in these standards, all tires must carry a guarantee against defects in workmanship and material as well as give satisfactory service under normal operating conditions.
(h) Labelling.
No person, firm, association or corporation shall sell, offer or expose for sale, or having in his possession with intent to sell any motor vehicle tire or motorcycle tire which has been retreaded or recapped unless the fact that such tire has been retreaded or recapped and the name and address of the person, firm, association or corporation which has done the retreading or recapping is plainly shown by a mark or label in the English language on both side walls thereof. (General Business Law, § 391.)


Equal to that of new 100 level tire of same size and type–minus tolerance 2/32″.
15 CRR-NY 51.4
Current through May 15, 2022
End of Document