- We are a professional manufacturer of U bolts with independent forging, bending and surface treatment workshops. We control the entire production process, from inspection of raw materials to the packing of the finished product. All our U-bolt clamps are tested for size and tensile strength before delivery and are assured to be free of defects.
- We have a wealth of experience working with global engineering contractors and hardware distributors. We fully understand the standard requirements of the European, African, Canadian and South East Asian markets. We offer a wide variety of product types including standard, stainless, galvanized and heavy-duty customized U bolt solutions.
- Our professional sales and technical team offers fast one-stop service. We are fast in replying to specification confirmation, sample application and bulk order requests. We have flexible OEM cooperation and stable batch delivery to establish long-term win-win cooperation with our customers all over the world.
u bolt
Stop pipe slippage before it starts.
Heavy‑duty grip at factory prices.
Corrosion fails? Switch to Sinsun.
Contact usU Bolts Factory | Stainless Steel & Galvanized U Bolt Clamp - Sinsun
Sinsun is a professional U bolts factory and reliable global top supplier. We manufacture premium stainless steel U bolts, galvanized U bolts and square U bolt clamps. Get standard 2 inch & 4 inch U bolts with stable clamping performance for industrial & construction projects.
Get a Quick QouteU Bolts Factory – Sinsun Top Fastener Supplier & Manufacturing Partner
U bolts factory with 17+ years of experience. Partner with a leading fastener supplier for round, square, stainless steel and galvanized U bolts. Direct pricing & fast lead times.
WHAT IS A U BOLT?
U bolts (sometimes called U bolt clamps or bolt U clamps) are a type of threaded fastener in the form of a U with two threaded ends and nuts to suit. In Europe they are called boulons en U, and in Spanish speaking countries they are pernos en U.In addition to tubular and circular structural components, these specialized fasteners feature fixed support and stable clamping. U bolts with diameters of 2 inches and 4 inches are commonly used in pipeline fixing and mechanical mounting jobs around the world.
Sinsun is the professional U bolt manufacturer with mature integrated production lines and strict quality control systems. Most generic suppliers provide only finished products in standard sizes and single surface treatment options. The material, bending angle and anti-corrosion coating will be chosen according to the client's actual working environment. All of our U bolt products conform to ISO and DIN industrial standards, featuring a uniform thread pitch and smooth twisting radian. This is to avoid pipe abrasion and loose clamping.
Global procurement clients complain about deformed bending, thread slippage, and the short anti-rust life of low quality U clamps. We address these core pain points by using one-time precision bending and high-standard heat treatment technology. Our stainless steel U bolts and hot dip galvanized U bolts provide stable clamping forces in long term vibration and outdoor exposure. We also support non-standard size customization to meet specific engineering and mechanical installation requirements.
Send inquiry Now
Round U Bolts (Round bend U Bolts)
Send inquiry Now
Square U Bolts
Send inquiry Now
Stainless Steel U Bolts
Send inquiry Now
Galvanized U Bolts
Send inquiry Now| Pipe OD (mm) | Rod Diameter (d) | Inside Width (mm) | Leg Length (mm) | Grade |
| 20 – 22 | M6 | 25 | 50 – 80 | 8.8 |
| 25 – 28 | M8 | 32 | 60 – 100 | 8.8 |
| 32 – 35 | M10 | 40 | 70 – 120 | 8.8 |
| 38 – 42 | M12 | 50 | 80 – 150 | 8.8 |
| 48 – 52 | M16 | 60 | 100 – 200 | 8.8 |
| 60 – 65 | M20 | 75 | 120 – 250 | 8.8 |
| 76 – 82 | M24 | 90 | 150 – 300 | 8.8 |
We also produce imperial sizes (1/4″ to 1½″ rod diameters, UNC threads), fine thread pitch upon request, and custom inside widths up to 300 mm. All dimensions follow DIN 3570 or ASME B18.31.5 standards.
| Parameter | Specification |
| Standards | DIN 3570 (piping & structural supports) / ASME B18.31.5 (threaded ends) / ISO 9001:2015 |
| Bend Types | Round (semicircular), Square (90‑degree), Semi‑Round (flattened), Offset (unequal legs), Forged Top |
| Material | Carbon steel (Q235, C1022, 10B21, 35K), stainless steel (SS304 / SS316), alloy steel (40Cr, 35CrMo, SCM435) |
| Strength Grades | 4.8, 8.8, 10.9 (metric) / Grade 5, Grade 8 (imperial) / A2‑70, A4‑80 (stainless) |
| Thread Type | Metric coarse & fine; UNC / UNF inch threads; fine thread UNF available |
| Surface Finish | Hot‑dip galvanised (ASTM A153, 45‑85 µm), electro‑zinc plated (ASTM B633), black oxide, Dacromet (zinc flake), powder coating, plain |
| Leg Length | 50 mm – 500 mm (2″ – 20″) custom |
| Inside Width | 20 mm – 300 mm (0.8″ – 12″) custom |
| Rod Diameter | M6 – M36 (metric) / 1/4″ – 1½″ (imperial) |
| Thread Tolerance | 6g (plain finish), 6h (plated finish) |
| Tensile Strength (Class 8.8) | ≥800 MPa |
| Yield Strength (Class 8.8) | ≥640 MPa |
| Rolled Threads | Yes – standard on all orders (superior thread structure and torque transfer) |
Main Applications of U Bolts
Engineering for pipelines and plumbing
U bolt clamps are necessary fixing parts for water pipes, gas pipes and industrial fluid delivery pipelines. Standard 2 inch U bolts and 4 inch U bolts are perfectly suited to common pipeline specifications to stabilize pipe positions. They effectively reduce vibration and displacement of the pipeline caused by the pressure of fluid flow. Galvanized U-bolts are widely used in outdoor municipal plumbing systems for long-term anti-rust protection.
Construction of buildings & steel structures
Square U bolts are best for fixing square steel tubes, structural supports and building guardrail frames. Their right angle bend design fits square components snugly, without offset or shaking. The bolt is used for joining and fastening auxiliary steel structures in building frames and bridge projects. High-strength forged U-bolts ensure long-term stability of the overall structure during construction.
Equipment - Mechanical & Agricultural
There are different kinds of bolt U clamps for fixing equipment bases, suspension parts, mechanical auxiliary components, etc. They resist loosening during mechanical operations due to vibration, and improve equipment service life. Square U bolts are ideal for agricultural machinery frames and tool mounting structures. Standard round U bolts fix different industrial devices to roller and tubular part fixings.
Marine & Offshore Plants
316 stainless steel U bolts are adapted to harsh marine environments with strong corrosion resistance to salt water. They repair pipelines on offshore platforms, ship deck pipelines and coastal facility supports. These bolts can offer stable clamping performance in conditions of high humidity and strong wind. They rarely oxidize or deform after long-term exposure to the marine outdoor environment.
For U-bolts, Standard wrenches and torque wrenches work best to control tightening force and avoid bolt deformation.
real customer feedback
Hot FAQ
Why Select Sinsun for U Bolts
Keep In Touch
TO KNOW MORE ABOUT Sinsun, PLEASE CONTACT US！
We are committed to providing you with the best quality service and look forward to communicating with you to solve problems together and bring you a better experience.
our experts will solve them in no time.