Equipment

Our equipment can be categorized into two groups:

       ● Prestressing Equipment

       ● Heavy Load Lifting Equipment

PRESTRESSING EQUIPMENT:

Stronghold system was officially launched in 1974 at the FIP Convention in New York, USA. It was among the leading few systems in the world at the time that was developed for multi-strand prestressing. Since its launch it has been incorporated in innumerable projects world-wide with many notable structures including cable-stay bridges being built on the Stronghold system.

Our prestressing jack ranges from mono-strand jacks that are typically used in post-tensioned slabs and in pre-tensioning applications to multistrand jacks that are employed for post-tensioning in bridges and other heavy civil structures.

We have a large selection of jacks to stress a range of different cable sizes. These jacks possess the universal ability to stress any form of cable composed of wires or strands that is individually anchored by means of wedges. Whatever the pattern or angular disposition assumed by the cable, Stronghold jacks can stress a given strand with only 30cm of end projection irrespective of the strand orientation.

Please note that from time to time we update our equipment inventory based on the market needs. Therefore, in addition to our Stronghold jacks we also carry stressing equipment from other vendors that are custom made and compatible with our Stronghold system. Accordingly, we are in position to offer prestressing services without requiring a third party assistance/equipment.

De-tensioning jacks are employed in pre- tensioning applications when the strands projecting beyond the precast section that has attained its desired concrete strength have to be de-tensioned. Our inventory includes such jacks with de-tensioning capability upto 1000 metric tonnes.

Stronghold pump Type-B are the commonly used pumps to operate the Stronghold pre-stressing jacks. These pumps operate at high pressure for stressing and low pressure for retracting. A double control valve separates stressing and lock-off operations, the latter being pre-set before delivery. A manual relief valve enables pressure to be gradually reduced, so ensuring uniform transfer of jacking force to the cable. A large capacity oil tank is incorporated fitted with a tubular indicator gauge. The pump is mounted on a pair of wheels for maximum mobility.

Grouting Machines

Stronghold grouting machines MX-5 and MX-7 are the two models for grouting applications with different capabilities.

Model MX-5

It is the most commonly used model and weighs 770 lb. (350 Kg) when empty. It has two chassis wheels plus a front caster for greater mobility over irregular ground. A second caster is mounted for towing the machine horizontally. Two vertically mounted pans of 3.17 cu. ft. (90 liters) capacity each ensure continuous mixing and delivery to the pump. This has a triple worm drive for pumping the grout continuously to the point of injection. The MX-5 will develop a maximum pressure of 220 Psi(1.52 MPa) and a maximum delivery of 53 cu.ft. (1500 liters) per hour.

Model MX-7

The MX-7 is an electrically driven high pressure grout injection machine incorporating two horizontally mounted independent mixing pans of 9.36 cu. ft. (265 liters) capacity to ensure continuous delivery. The machine will develop a maximum pressure of 234 psi (1.61 MPa) when displacing an optimum grout output of 2.74 cu. ft (76 litres) per minute. Overall dimensions are 2.23m x 0.87m x 1.5m.

HEAVY LOAD LIFTING EQUIPMENT:

Stronghold has special flat jacks ranging from 40 ton lifting capacity to 200 ton lifting capacity and of different over-all heights. We are in a position to undertake lifting jobs independent of any foreign assistance both technically and equipment wise. We have available with us over 100 jacks of different capacity at present.

The tallest jack has an overall height of 325mm with a lifting capacity of 200 tons. These are typically utilized when adequate space is available for jacking. Where available space is limited our smaller jacks e.g. 40 tons jacks with overall height as little as 30 mm are utilized.