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DTI Washer

DTI Washer manufacturer in India 

DTI Washer manufacturer, DTI Washer supplier,DTI Washer  exporter, DTI Washer trader in India - Bhalla Fasteners

DTIs, are single use mechanical load cells used to indicate when the required tightening torque has been achieved in structural fastener assemblies.

Direct tension indicators are hardened washer shaped components with 4 to 6 small arch-like protrusions on the bearing surface that are designed to deform in a controlled manner when subjected to appreciable tightening torque.

Basically the Direct tension indicators washers work on the principle that appreciable tightening force on the bolt nut assembly the arch like protrusions collapse under the applied load and this indicates that the required torque has been applied in tightening the assembly. The gaps in between the washer and nut are normally checked with thin feeler gauges. In some cases the protrusions are filled with certain silicone material which flows out from the protrusions and through the crevice in the washer towards the outer edge thus indicating that appreciable torque has been applied in tightening the assembly. These washers are known as Squirter Washers because the silicone is squirted out from the protusions as the washer flattens out with increasing load. 

High quality alloy steel/C-65 spring steel material used in the manufacture of direct tension indicators washers shall be designed, processed, heat treated, and protectively coated as required. These direct tension indicators washers are manufactured to conform to required international standards for chemical composition, load, and dimensions.

Functioning

DTIs are a function of induced tension. As the fastener assembly is tightened, the arch-like protrusions are compressed and the change in distance between the base of the protrusions of the DTI washer and the protrusion apex correlates to a value of tensile force induced into the fastener. This distance can be verified by insertion of a tapered feeler gage between the protrusions to the bolt shank. The number of instances the bolt shank can be reached by the feeler gage is then compared to either the results of a pre-installation verification procedure or the manufacturer's instructions.

DTI washers indicate the amount of torque applied to tighten the assembly is a function of induced tension. As a fastener assembly is tightened, the arch-like protrusions are compressed and the change in distance between the base of the protrusions of the DTI washer and the protrusion apex, indicate the amount of tensile force induced into the fastener assembly.

Common uses of DTI washers are in machinery and heavy structures like road and rail bridges and also building structures. Inspection entails that structural engineers randomly check the fastening units with tapered feeler gauges. Though the washers are made to international standards the same can be cross checked by using torque indicating wrenches which give a reading of the applied torque. Nowadays it is mandatory for design engineers to specify the use of DTI washers because of this inherent characteristic.

DTI Washer can sit on the structural member or be separated by a washer, but it should never be installed with the bumps facing the member and it should never be touching a rotating surface.

Bhalla Fasteners manufacture these DTI washers according to the ASTM F959 & EN-14399-9 standards. DTI Washersby defination stands for ‘Direct Tension Indicator Washers’ and is mostly used to measure the bolt tension developed during the tightening process  regardless of the torque resistance of the bolt. At Bhalla Fasteners we usually manufacture these  washers in  C-45, 8.8 and 10.9 grades in sizes M12 to M36 Bhalla Fasteners is among the largest manufacturers of DTI washers in India and exporter to Europe and is known for the high-quality, reliable products that we produce.

DTI Washer is the world’s simplest cost effective solution to control the tensioning of bolts. These unique, patented fasteners deliver consistent, reliable bolt tension, along with installation and inspection efficiency. They are used every day to achieve required tension loads on bolts in countless applications including: structural steel buildings and bridges, studs used in the petro-chemical industry, anchor bolts and SAE cap screws for automotive applications. This washer is also known as ASTM F959 Washer.

Bhalla Fasteners is the leading manufacturer, supplier, exporter, trader of DTI washer in Kolkata, Coimbatore, Salem, Chennai, Hosur, Hyderabad, Andhra Pradesh,Gujrat, Karnataka, Kerala,  Perambur, Ennore, Ambattur, Pune, Mumbai, Nasik, Aurangabad, Nagpur, Chandrapur, Ichalkaranji, Jalgoan, Kohlapur, Sriperumpudur, Meerut, Durgapur, Kharagpur, Kalyani.

Bhalla Fasteners is the leading  manufacturer, supplier and exporter of DTI washers in USA ,UK ,Poland, Germany ,France, Spain, Belgium, Greece, Denmark, Estonia, Hungary, Austria, Portugal, Finland, Czech Republic, Sweden, Latvia, Lithuania, Slovakia, Croatia, Bulgaria, Austrailia, Scotland, Panama, Ireland, Netherlands, Italy, Canada, Mexico, Brazil, Argentina, Colombia, Cuba, Peru, Chile, Costa Rica, Paraguay, Uruguay

Bhalla Fasteners is the leading manufacturer, supplier, exporter, trader of DTI washers  in Kolkata, Coimbatore, Salem, Chennai, Hosur, Hyderabad, Andhra Pradesh,Gujrat, Karnataka, Kerala,  Perambur, Ennore, Ambattur, Pune, Mumbai, Nasik, Aurangabad, Nagpur, Chandrapur, Ichalkaranji, Jalgoan, Kohlapur, Sriperumpudur, Meerut, Durgapur, Kharagpur, Kalyani.

Loading Indicating Washer manufacturer in India-Bhalla Fasteners 

Load indicating washers (LIW) are used to develop the correct tension when installing A325 or A490 structural bolts used in construction. Standard DTIs and loading indicating washers are made to ASTM F959. Load indicating washers may be available for other bolt grades and made on order.

DTI washer weight chart 

I Size/GradeOD Min. [mm]OD Max. [mm]ID Min. [mm]ID Max. [mm]Thickness Min. [mm]Thickness Max. [mm]Number of ProtrusionsWeight [kg/pc]
M12 25.730.213.313.42.64.640.017
M16 32.436.816.7516.853.25.540.023
M20 40.44620.9521.053.66.050.029
M22 42.450.623.0523.153.66.050.045
M24 48.455.225.1525.254.07.060.048
M27 54.162.128.328.44.07.060.089
M30 58.169.031.4531.554.07.070.097
M36 70.182.837.7537.854.87.080.116

Product
DTI Washer