Dubai Metro

The Dubai Metro System will be built around top-of-the-class modern trains, fully air-conditioned and customized to meet Dubai specific requirements. Each train will be approximately 75m long, consisting of 5 cars, with numerous double doors allowing fast and smooth flows of passengers in station. A key objective of the engineering studies is to minimise the impact on road traffic, and more generally, on city life during the works........

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Welcome to Pretread.com, your relayable source for ..neoprene bridge bearing, bearing pads, laminated elastomeric bearing, elastomeric bearing,.. moulded rubber products, precure tread rubber, tread liner,ptfe teflon sliding,ptfe teflon sliding, ptfe ptfe teflon pipe supports, molded rubber products, rubber gaskets, and rubber marine fenders. Our home page and connected links provide information on a wide range of rubber products.

Why use laminated elastomeric rubber bearings for bridges and buildings ?

A bridge basically consists of bridge deck supported by piers. In order to avoid damage by movements of vehicle and thermal expansion, loading to piers,bridge bearings are used to accommodate these movements so as to reduce reaction forces and bending movement to within safety limits of structure. Neoprene as well as Natural Rubber are ideal engineering material for bridge bearings as it is highly elastic and sufficiently soft to accommodate these movements without transmitting harmful stress and also it absorbs and isolate energies from impacts and vibrations. Bridge bearings are devices for transferring loads and movements from deck to piers.

Pretread.com is direct manufacturer of Laminated Neoprene Bridge Bearings and Laminate Elastomeric Bearings. We at pretread.com, manufacture neoprene bridge bearings, elastomeric, pads, high damping rubber bearing, expansion joints, PTFE sliding bearing, sliding bearings to AASHTO M 251- Bridge Bearings, AASHTO (American Association of State Highway and Transportation Officials) EN 1337-3:2005, BS / DIN specifications for first time in, Middle East from U.A.E. Laminated elastomeric bearings, bridge bearings, bridge bearing pads high damping bearing pads are manufactured mostly in neoprene elastomeric compounds.

Types of Bearings manufactured by us.

Plain and Laminated elastomeric bridge bearings

We manufacture plain and laminated elastomeric bearings for construction industry in neoprene and natural rubber compound confirming to BS/AASHTO/DIN standards.Plain elastomeric bearing pads or strips and compression moulded to specified thickness and sizes and laminated bridge bearing pads are manufactured with many layers of Mild Steel and elastomer layers in ..neoprene rubber compounds,.. unless other wise specified for natural rubber compound. Our specialization is in neoprene bridge bearings, elastomeric, pads, high damping rubber bearings are from our years of experience, and with support from our technical and marketing partners.

Laminated elastomeric bearing designing.

We offer in-house facility to design bridge bearings confirming to both AASHTO LRFD as well EN 1337-3:2005. We can varify ..load calculations.. for your bearings. On receipt of corbel size, load and movement details of your requirements, calculations and bearings sizes can be provided based on results on parameters compared AASHTO M251 or EN 1337:2005.

Bearing design AASHTO M 251

Bearing design sheet confirming to AASHTO LRFD

Bearing design EN 1337:2005

Bearing design sheet confirming to EN 1337-3:2005

High Damping Rubber Bearing (HDRB)

As an alternative to the lead rubber bearing,we offer high damping rubber bearing (HDRB) which is ideal for seismic isolation with one device - supporting the structure, providing the elastic restoring force and also the required amount of damping up to a maximum of 10-15% of critical. Moderate damping is achieved with this type of the bearing.

The HDRB isolation bearings are vertically stiff, capable of supporting vertical gravity loads, while being laterally flexible, capable of allowing large horizontal displacements. In effect, the ground is allowed to move back and forth under a base isolated during an earthquake, while leaving the building to remain "stationary." By means of its flexibility and energy absorption capability, with HDRB rubber bearings isolation system partially reflects and partially absorbs some of the earthquake input energy before this energy can be transmitted to the structure. The net effect is a reduction of energy dissipation demand on the structural system, resulting in an increase in its survisability.

Significantly reductions of structural and non-structural damage may be achieved through the use of HDRB rubber bearings seismic isolation. Reduction in elastic-force reductions by factors of 5- to 10- are possible. Expressed in simple terms with regard to building performance, this is roughly equivalent to a reduction of a Richter-magnitude-8 event to an event in the 5-to-6 magnitude range. Clearly, this is a very significant reduction. These potential benefits are greatest for stiff structures fixed rigidly to the ground, such as low- and medium-rise buildings, nuclear power plants, bridges and many types of equipment. Some of the heady duty bearings supplied by us and installed in structures in Pakistan has helped to minimize damages to the structure as will as human life.

Recent disasters caused in many parts of the world have due to earthquake has made many structural designer to start using with HDRB rubber bearings base isolation systems to building and structures. We have few Projects in hand are very keen to work on such Projects and you are requested to contact us.

Ptfe sliding bearings.

We offer both ptfe (Teflon) sliding pads as well as teflon sliding bearings. Ptfe Sliding bearing pads can be used for lower loads and Sliding Bearings (with laminated bearing or carbon steel backing alone)for higher loads. Both ptfe teflon sliding, teflon Sliding bearings as well as sliding bearing pads are supplied with appropriate thickness SS 316 L plates with mild steel backing plates for ptfe pipe supports.

Ptfe sliding bearings can be manufactured both in rectangular and disc type. Modern day construction requires large span movements for buildings and www.pretread.com has the solution for you. Especially in constructing Shopping Malls where spans are very wide and movements are over 100 mm movements, effective and economical solution is to use our ptfe teflon sliding bearing combination with laminated neoprene elastomeric bearing and as ptfe pipe supports.

Ptfe teflon pipe supports

In application as pipe supports, PTFE Slide Bearings are superior to conventional expansion plates, rollers and rocker arm type supports. Ptfe Teflon pipe supports, accommodate expansion, contraction and other reciprocating motions of any structure that moves as a result of thermal expansion, Seismic or differential forces. Laminated Bearings for pipe support applications must operate at high loads and low speeds, and under these both conditions the self-lubricating properties of PTFE are exposed to maximum. This factor, together with its no stick-slip and anti-weathering characteristics, is the principle reason on why PTFE has proved to be so successful as a slide bearing material.

Advantages of ptfe sliding pipe supports.

The simplicity of the bearing design and its ease of fabrication and installation make the unit cost efficient. The costs of a construction can be reduced by designing for expansion rather than strain. Coefficient of friction over the bearing surface remains constant, even under worst case conditions. bearings are maintenance free - PTFE is inherently self - lubricating, while dirt particles are absorbed into the material. Only simple protection is required against the significant increases of dirt.

Design / Selection of ptfe sliding pipe supports.

AARP offers a specialist service, based on many years experience in the use of PTFE and its application to slide bearings to assist in the design of bearing systems. Low friction sliders with coefficient of friction less than 0.1 are available. They are designed specifically for the loads and movements required. Most assemblies are also designed to be compatible with our range of standard sliders and glides, Also 'stand alone' Slide Bearing Sandwich Plates are available. ptfe teflon sling beaing assemblies AARP Slide Bearings consist of a single PTFE pad hot bonded to MS plate which can be welded to plate supports and the top polished to mirror finished stainless steel plate to slide over it. The assembly is designed to ensure that the PTFE pad is covered by the S/S plate throughout the expected design movements. The basic element is a 2.5 mm PTFE sheet, hot bonded to 4 to 8 mm mild steel backing plate for straight forward field installation by welding. Where operating conditions require them, thermal insulation and vibration damping pads may be bonded between the PTFE sheet and the backing plate as plain neoprene pads or in some cases as lamainted elastomeric bearings to be installed between the backing plate and the structure. To allow operation at high ambient temperature, a hot bonding system is used for bonding, and the adhesives are cured under strictly controlled conditions, of 140 degrees C and 200 Kg pressure to ensuring that the bond is stronger than the PTFE itself. Usualy such bonding is carried out in a special hydraulic press As standard glass filled PTFE as well as black filled ptfe also is used as the bearing material, where much higher bearing loading as well as lower deformation under loads are required.

ARP-NEOSLIDEPAD

Building structural design has taken a considerable change over the last decade. The sizes of spans have grown bigger, difference of internal and external temperature has become greater and global warming has changed climatic changes. These factors have exerted great demand on elastomeric bearing design and requirements. New polymer types and combinations with Stainless Steel have paved way for new designs. Thus we offer a combination of elastomeric bearing with ptfe known as ARP-NEOSLIDEPAD for PTFE sliding bearing requirements.

ARP-NEOSLIDEPAD - (PTFE Sliding bearing system with Stainless Steel Top and Neoprene Protective Seal) are specially designed, manufactured and assembled with a combination of polyamide or steel reinforced neoprene bearing pad with PTFE top and a SS 316 L plate sliding over top as a whole unit protected with a soft neoprene seal.

Lead Rubber Bearings LRB

A lead rubber bearing is a bigger laminated bearing manufactured from layers of rubber, sandwiches together with layers of steel, except for that in middle of bearing there will be a solid lead "plug." Top and bottom of the bearing is fitted with steel plates, which are used to attach bearing to building through its foundation.

Lead rubber bearings are designed in such a way that bearing is very stiff and strong in vertical direction, but flexible in horizontal direction. Lead, inserted as center core of bearing dissipates the energy of earthquake while the rubber, reinforced with steel plates, provides stability, supports structure and isolates vibrations.

Bearing Installation

General information on installation of bearings are available from Installation - Bridge Bearings and will provide bearing installation procedure on laminated bearing pot bearings as well as ptfe teflon bearings.

Other rubber products manufactured by us.

In addition to neoprene bridge bearing, bearing pads, laminated elastomeric bearing, elastomeric bearing,.. moulded rubber products, precure tread rubber, tread liner,ptfe teflon sliding,ptfe teflon sliding, ptfe ptfe teflon pipe supports, molded rubber products, rubber gaskets, and rubber marine fenders. tire retreading equipment,ptfe teflon sliding moulded rubber products, molded rubber, shock absorber mountings, molded rubber products etc.

Tire Retread Materials - Tread Liner

For truck tire retreading we offer camelback, precure tread rubber, moldcure rubber etc from our Middle East Plant, situated in Seif-Zone Sharjah, Dubai, U.A.E.More information on Retread materils, precure rubber and pctr tread inner are available form this site.

Our quality assurance.

We are the first and only laminated bearing manufacturing facility in Middle East to have an in-house bearing testing facility to carry out tests confirming to AASHTO specification in accordance with Acceptance Testing on either Level I or Level II as well as Short/Long-Duration Compression Test. Our bearing testing machine can test bearings up to Vertical load of 4200 kN with horizontal shear load up to 400kN and movement up to 100 mm meeting AASHTO (American Association of State Highway and Transportation Officials) or EN 1337-3:2005 specifications

Under one roof with stringent quality control, with technical and marketing support from our Technical Partners we manufacture neoprene bridge bearings, ptfe pipe supports, laminate elastomeric bearings, bearing pads, pot bearings, PTFE sliding bearings etc to EN 1337-3:2005, AASHTO M 251- Bridge Bearings,AASHTO(American Association of State Highway and Transportation Officials.

This web site has a wealth of information on our product lines and general information which we try to updated quite often. We hope you will find our site very informative and will contact us for further details and inquires.Click on below link, to obtain regular archive on our site.