Anchor Bolt

Anchor Bolt Production Completed

High Strength Anchor Bolt

Wind turbine anchor bolt raw material is 42CrMoA and other equivalent materials. It is purchased from large and qualified steel mills. Each steel round bar went through ultrasonic flaw detection before delivery. According to GB/T 4162 standard, reaches Class A level. LongTeng guarantee high strength anchor bolts supplied can meet or even higher than the technical specifications required in bidding documents.

Our high strength anchor bolts for wind turbine are manufactured following strict standard production process: anchor bolt is heat treated and then threaded: anchor bolt is tested after heat treatment, then peeled and drawing is processed to the specified medium diameter size. Peeling process can remove oxide scale and decarburization layer generated during heat treatment; and the last is screw thread.

Anchor Bolt Package Method
Anchor Bolt Stock For Customer

Note: The middle part of wind turbine anchor bolt is not machined, it is one-time forming and thread precision is better.

Patent for High Strength Anchor Bolt

High Strength Wind Turbine Anchor Bolt Production Process:

Production Process Flow

Purchase raw materials according to plan (designated steel mill materials and grades) → Raw material Inspection → rough straightening → heat treatment (medium frequency induction heat treatment) → inspection (performance test) → peeling and fine alignment (100% ultrasonic flaw detection, fluorescent magnetic particle inspection, etc.) →Unloading→Machining (Chamfering)→Coded→Thread Rolling→Inspection (Threading Precision Gauge, Medium Diameter Micrometer, etc.)→ Anchor Bolt Tension Detection→ Anchor Bolt Anticorrosion Treatment (Dakro, coated according to customer requirements) Grease + heat shrinkable tube, etc.) → inspection → packaging → storage.

Inspection Equipment

Anchor Bolt Test after Production:

Tensile Test: We make 100% tensile test to steel bars according to client’s request, tensile strength is 70% of the yield strength.(A bit higher than actual tensile strength).The elongation or re-condensation within ≤±0.02mm/m.

Anti-Corrosion Test: We use anti-corrosion grease+anti-corrosion belt +PVC tube+sealing nut to achieve the purpose. After 1000 hours’ salt spray test, there will be no corrosion on the products’ surface.

Anchor Cage Bolt Assembly Parts:

Anti-Corrosion Treatment Anchor Bolt
Cap and Nut for Anchor Bolt

Dimension of Class 10.9 Anchor Bolt - Longteng

Anchor BOLT Grade 10.9
D NomDiameter at smooth partPitchCross SectionYield forceUltimate force

Dimension of Class 8.8 Anchor Bolt - Longteng

Anchor BOLT Grade 8.8
D NomDiameter at smooth partPitchCross SectionYield forceUltimate forceWeight/meter

Mechanical Properties of Available Anchor Bolt Grades

GradeDiaTensile Strength Rm/MPa2% Elongation Limit RP 0.2/MPaStress Under Proof Load SPf/MPaElongation after fracture A/%Reduction oF Area after Fracture Z/%Rockwell Hardness /HRCBolt Length mm-40 ℃ Impact Absorb Energy K/J
8.8M16 ~M56830660600125223341200027

Our anchor bolt products have super high yield strength(up to 1100 MPa) and tensile strength(up tp 1220 MPa). Regarding impact energy, our grade 8.8 anchor bolt everages 60J , grade 10.9 everages 35J which means our products performance much higher than standard requirements.

Recognized Steel Grades for Anchor Cage Bolts

Anchor Bolt Steel StandardSteel Grade&Tensile Strength
ISO 4014Grade 8.8
ASTM A615 / A615MGrade 75 (690 MPa [100 ksi] minimum tensile strength)
ASTM A722 / A722M(1035 MPa [150 ksi] minimum tensile strength)
ASTM A193 / A193MGrade B7 (860 MPa [125 ksi] minimum tensile strength)

Chemical Composition Comparsion of Anchor Cage Bolt Rod

CountryChemical Composition Comparsion of Anchor Cage Bolt Raw Material
Steel GradeCSiMnPSCrMo