U BOLTS

description

The “U”, shape of the bolt keeps it firmly in place, adding security and stability to the join. U bolts are used as framing fasteners and anchors for foundations and roofs, pipe and conduit holders and bolts for motor and engine shaft components.
U Bolts are used heavily in building and construction, offshore and onshore piping, Ship building, chemical, electromechanical and petrochemical industries, etc.

WHY U BOLT COATING?

Corrosion at pipe supports is one of the leading causes of process piping failures. It is the beam supports and saddle clamps that have historically caused the majority of problems.
The causes leading to Corrosion:
• Water is trapped.
• The paint system fails (atmospheric coatings soften in immersion service).
• Corrosion is initiated.
• Corrosion undercuts paint film.
• Crevice corrosion starts.
• Pipe fails.

So the solution is they simply and economically address the root cause of crevice corrosion by:
• Eliminating crevices.
• Eliminating water entrapment.
• Eliminating metal-to-metal contact.
• Allowing for ease of inspection and maintenance.
• Providing complete support to the piping system.

TYPES OF COATING

• Rubber Coatings
• Polyurethane Coatings
• PTFE Bonded

Rubber Coatings

Prevents paint failure and corrosion problems. A rubber lined U-bolt eliminates corrosion problems between steel U-bolt and pipe and thus saves your piping systems and extends lifetime. Also helps in reduction of noise and vibration.

RUBBER COATING MATERIALS

Natural Rubber: A combination of high tensile strength, high abrasion resistance, high load bearing capability, rebound elasticity, very good low temperature flexibility, excellent dynamic properties and low heat buildup makes Natural rubber indispensible in several applications.

Styrene Butadiene Rubber (SBR): Dynamic fatigue resistance, ageing, abrasion and heat resistance are some of the qualities of SBR. SBR being non-polar are poor conductors of electricity, they are also non-compatible with gasoline and oil applications.

Acrylonitrile Butadiene Rubber (NBR): Has excellent mechanical properties. NBR being polar has good resistance against gasoline, grease, mineral oils, alcohols (Methanol, Ethanol), however they have a considerably higher electrical conductivity compared to non-polar rubbers.

Neoprene: They have favorable flame-resistant properties and a higher level of ozone resistance comparable to other polymers. Gas permeability is distinctively superior. Being polar they are sufficiently oil resistant for many applications.

Ethylene Propylene Diene Monomer (EPDM): Exceptional heat and ageing properties. Ozone and weather resistance is excellent even after months of exposure to ozone rich air. The electrical insulating and dielectric properties or the breakdown and corona resistance is excellent. Resistance to chemicals and sea water is very good, however swelling takes place if exposed to gasoline or oils.

Silicon Rubber: Can survive long time exposure to hot air with intact elasticity. Extraordinarily resistant to ageing, weathering, ozone and high temperature. They have excellent low temperature flexibility and very high ignition temperature of upto 200ºC. The tensile strength, impact and abrasion resistance is poorer compared to other polymers.

FKM Viton Rubber: Has the best heat resistance of all rubbers. They resist swelling in most oils, acids and chemicals; however, their mechanical properties are distinctively lower compared to other polymers.

U Bolt Materials

GALVANIZED

HOT DIPPED

ZINC PLATED

304 STAINLESS STEEL (A2)

316 STAINLESS STEEL (A4)

TYPES OF U BOLT

GRIP TYPE

SILICON RUBBER

PTFE BONDED

D TYPE

POLYURETHANE COATED

PTFE BONDED

Polyurethane Coatings

The polyurethane coated U-bolt are a seamless, vulcanized material that can be applied to all types of U-bolts. These U-bolt’s are excellent for eliminating corrosion problems on piping in refineries, chemical plants, paper mills, rigs and the shipping industry. Polyurethane has good tensile strength and weather resistance, excellent abrasion, tear and hydrolysis resistance and a fair degree of chemicals resistance. They have better thermal stability than most general-purpose rubbers and plastics.

PTFE Bonded

PTFE coatings on the “U” bolts normally come as an inner lining on the rubber sleeve. This is done where low coefficient of friction and anti-stick properties is required on the pipe installation.

Polytetrafluoroethylene (PTFE), is a thermoplastic member of the fluoropolymer family of plastics. PTFE has a low coefficient of friction, excellent insulating properties, and is chemically inert to most substances. It also can withstand high heat applications and it is well known for its anti-stick properties

Fields of application:

• For galvanized and SS pipes in offshore and onshore piping
• Shipbuilding, chemical and petrochemical industries.
• Gas distribution systems, LPG and LNG plants.
• HVAC

Features & Advantages:

• Reduce or eliminate noise and fatigue due to vibration of pipework against the supporting structure
• Prevention of galvanic corrosion due to the contact of dissimilar metals in the presence of an electrolyte
• Prevention of wear and / or crushing of composite, thin wall or non-ferrous pipework
• Fire retardant rubber molded components do not support the surface spread of flame
• Low evolution of toxic gases
• A wide range of standard sizes
• Operational temperatures range from -50ºC to + 200ºC continuous, 220ºC intermittent.
• Serrated inner-face on “grip-type” provides positive pipe retention.

cross section of u bolts

DIMENSIONS

NOMINAL PIPE SIZEINTERNAL LENGTHTHREAD LENGTHINTERNAL WIDTHCENTERDIAMETERHALF ROUND PAD DIMENSIONS
ABCDEFGHI
1/4 x 1/23 5/16″2 3/8″15/16″1 3/16″1/4″2 1/4″3/4″3/8″3/8″
1/4 x 3/43 7/16″2 3/8″1 1/8″1 3/8″1/4″2 1/2″3/4″3/8″3/8″
1/4 x 13 1/2″2 3/8″1 3/8″1 5/8″1/4″2 3/4″3/4″3/8″3/8″
3/8 x 3/43 7/16″2 3/8″1 1/8″1 1/2″3/8″3″3/4″3/8″1/2″
3/8 x 13 9/16″2 3/8″1 3/8″1 3/4″3/8″3 1/4″3/4″3/8″1/2″
3/8 x 1 1/43 3/4″2 1/2″1 3/4″2 1/8″3/8″3 5/8″1″1/2″1/2″
3/8 x 1 1/24″2 1/2″2″2 3/8″3/8″3 7/8″1″1/2″1/2″
3/8 x 24 9/16″2 1/2″2 7/16″2 13/16″3/8″4 5/16″1″1/2″1/2″
1/2 x 24 5/8″2 1/2″2 7/16″2 15/16″1/2″4 7/8″1″1/2″5/8″
1/2 x 2 1/25 3/16″3″3″3 1/2″1/2″5 1/8″1″1/2″5/8″
1/2 x 35 3/4″3″3 5/8″4 1/16″1/2″5 7/8″1″1/2″5/8″
1/2 x 3 1/26 3/8″3″4″4 1/2″1/2″6 3/8″1″1/2″5/8″
1/2 x 46 3/4″3″4 5/8″5 1/16″1/2″6 15/16″1″1/2″5/8″
1/2 x 58″3″5 5/8″6 1/8″1/2″8 1/2″1″1/2″5/8″
5/8 x 69 7/16″3 3/4″6 3/4″7 3/8″5/8″9 5/8″1 1/2″3/4″3/4″
5/8 x 811 7/16″3 3/4″8 3/4″9 3/8″5/8″11 5/8″1 1/2″3/4″3/4″
3/4 x 1013 3/4″4″10 7/8″11 5/8″3/4″14 1/4″1 1/2″3/4″7/8″
7/8 x 1216″4 1/2″12 7/8″13 3/4″7/8″16 3/4″1 1/2″3/4″1″
7/8 x 1417 1/4″4 1/2″14 1/4″15″7/8″18″1 1/2″3/4″1″
7/8 x 1619 1/4″4 1/2″16 1/4″17″7/8″20″1 1/2″3/4″1″
1 x 1821 5/8″6″18 1/4″19 1/8″1″22 1/2″1 1/2″3/4″1 1/8″
1 x 2024 5/8″6″20 1/4″21 1/8″1″23 1/2″1 1/2″3/4″1 1/8″
1 x 2427 5/8″6″24 1/4″25 1/8″1″28 1/8″1 1/2″3/4″1 1/8″
1 x 3035″6″30 1/4″31 1/8″1″34 1/8″1 1/2″3/4″1 1/8″
1 x 3640 1/4″6″36 1/4″37 1/8″1″40 1/8″1 1/2″3/4″1 1/8″