Installation of Conduits and Cables For Fire Suppression System
GI Conduits Installation
- Mark the cable route as per the approved shop drawing.
- Install the saddles using fisher and screw. If necessary, the GI conduit will be cut to the length required and threaded. Threading will be processed by stock and dies.
- Rotate the stocks and dies two and a half turns in clockwise direction and in a counter clockwise direction, to clear away the accumulated swart. This will enable the thread to be cut cleanly and efficiently without fear of stripping. Once completed, file across the leading edge of the thread and reamer the inner periphery. This prevents cable snagging on burred edges.
- Saddles shall support horizontal/vertical runs at interval not more than 1 meter. Bends shall be supported with two saddles on each side.
- Draw in boxes shall be provided after every two bends or more that 15 meters of straight runs.
- Conduit sockets complete with thread joint two lengths of conduits. In case of crossing or ending or at ‘T’ junction area, cross-boxes, “tee” boxes are normally used to link up conduit pipes.
- As soon as the conduits are fixed, site supervisor will check and inspect the site to ensure that the installations are according to the shop drawings. A formal request will be extended to the consultant engineer.
- Install the conduits by tightening the conduits to the saddle using screw.
- Extend the conduits length by connecting another length using GI couplers.
- Run the required cables through the conduit.
Installation of open clip cables
As an alternative you can install the fire suppression system electrical cabling as under:
- Mark the cable route as per approved shop drawing.
- Install the cables using the cable clips by installing the cable clips with cables using fisher and screw.
Installation of Fire Suppression System Devices
- Mark the location of the devices as per approved shop drawings.
- Cutting to be done as per the marking by the civil contractor.
- Fix the base of the devices using fisher and screw.
- Mark the cables as per the requirements (IN/OUT LOOP) if required.
- Terminate the cables to all devices as per the product catalogue.
Installation of Panels
- Mark the location of the panels as per approved shop drawings.
- Cutting to be done as per the marking by the civil contractor. (if recessed)
- Install the PVC conduits inside the wall cutting as required. (for concealed)
- Install GI conduits/Trunk to running the cable to the panel. (surface mount)
- Individual conduit should be installed for main power supply.
- Make necessary holes on the panels and install adapters.
- Install the panel using fisher and screw.
- Run the cables through the conduits/trunks up to panel.
- Identify the cables as with tags and terminate cables with ferrules.
- Terminate the cable to the Fire Alarm Circuit Board as per the approved shop drawing and product catalogue.
Installation Of Clean Agent Fire Suppression System
Identify the actual location of the cylinder based on the approved shop drawings.
Install the supports:
Mark the drill hole location on the wall corresponding to the mounting bracket supplied with the cylinder.
Drill the holes as per drop-in anchor size and install the mounting bracket on the wall using drop-in anchor bolts.
Install the Cylinders:
Mount the cylinder on the mounting bracket and tighten the cylinder on the mounting bracket with the supplied strap using bolts.
Painting of Pipes:
- Clean the black pipe with cotton rag to remove any dust or grease on the pipes.
- After cleaning, paint the black pipes with 1 layer undercoat of wash primer. Ensure all sides (top & bottom) are painted evenly.
- Put the painted pipes in a good ventilation condition for 24 hours for the paint to dry.
- After the paint is dried, then paint the pipes with 2 layer of finish coat. Ensure all sides (top & bottom) are painted evenly.
After the finish coat is dry, install the pipes as per approved shop drawings of clean agent fire suppression system.
Installation of Pipe Support
- Identify the actual location of the hanger based on the approved shop drawing. Mark the position for installing the drop in anchor after coordination with Structural Engineer.
- Cut the required length of the GI angle as per the site condition.
- Fabricate the support by welding the angles as per the approved shop drawing.
- Drill holes on the fabricated support for fixing the GI angle to the wall/slab and also for installation the pipes using U bolt as per require pipe sizes.
- Locate the required support locations as per the approved shop drawing and marks the holes to be drilled on the wall/slab.
- Drill the hole on the marked position as per the anchor bolt sizes.
- Insert the drop in anchor in the hole.
- Tighten the GI angles on drop in anchor using bolts.
- Rigid bracing is required at each directional change fitting, tee and nozzle.
- Cut the required length of the pipe to be grooved.
- Check that the cut ends of the pipe are square.
Install the correct die on the grooving machine for the corresponding pipe size.
- Insert the end of the pipe to be grooved in between the groover dies.
- Support the other end of the pipe using the pipe stand.
- Start the machine and at the same time apply pressure on the pipe toward the machine so that the pipe does not slip out of the groover die.
- Groove the pipe until the required depth of the groove is achieved.
- Pipe Cutting
- Cut the required length of the pipe to be threads.
- Check that the cut ends of the pipe are square.
- Install the Threading Dies
- Install the correct die head with threading teethes on the threading machine for the corresponding pipe size.
- Thread the Pipe
- Insert the end of the pipe to be threaded in-between the die head and tighten the chuck to hold the pipes properly.
- Support the other end of the pipe using the pipe stand.
- Start the machine and engage the die head into threading position.
- Thread the pipe until the required length of the thread is achieved.
- After the threading, loosen the chuck and remove the pipe.
- Drain the residual threading oil from the pipe into the oil tray of the threading machine.
- Groove the pipe ends according to the manufacturer’s specification, project specification and consultant’s approval.
- Pipe must be free from indentation, projection or roll marks on exterior from the end to the groove, to assure a leak tight seat for the gasket.
- Pipe must be free from indentation, projection or roll marks on exterior from the end to the groove, to assure a leak tight seat for the gasket. Refer to figure 1 next page.
- Place gasket over pipe ends, being sure gasket lip does not overhang pipe end.
- Align and bring 2 pipe ends together and slide gasket into position centered between the grooves on each pipe. No portion of the gasket should extend into the grove on either pipe.
- Loosely assemble all segment leaving on nut and bolt off to allow for “swing-over” feature.
- With 1 nut and 1 bolt removed, use the “swing-over” feature to position housing over gasket and into the grooves on both pipes.
- Insert the remaining bolt to allow easy tightening of the nut. Be sure track head engages into housing recess.
- Tighten nuts alternately and equally maintaining metal-to-metal contact at the angle bolt pads. Tighten securely to assure a rigid joint.
- Drill the hole according to the manufacturer’s specification, project specification and consultant approval.
- Remove 1 nut and bolt from housing. Loosen the other nut until it is flush with the end of the bolt. Remove the tape and lift the gasket from Mechanical-T outlet.
- Check gasket supplied to be certain it is suited for intended service. Apply a thin coat of silicone lubricant to gasket lips and outside of gasket.
- Reposition gasket into housing using alignment tabs on slides for proper positioning.
- Rotate the lower housing approximately 90° away from the upper housing in the hole.
- Make sure that the locating collar is in the outlet hole by rocking the upper housing in the hole.
- Insert bolts in his hole and finger tighten both nuts. Be certain oval-neck of bolt engages recess in housing. Make sure that the locating collar is in the outlet hole and the positioning lugs are properly aligned.
- Tighten bolt nut uniformly until the upper housing is in complete surface contact in the gasket pocket area and the assembly is rigid.
Screw Fitting Installation
- Check the pipe length required based on the approved shop drawing.
- Mark the desired length on the pipe and cut it. Make sure the pipe ends are square.
- Place the pipe in the threading machine and thread it accordingly. Make sure the thread of the pipe is in good condition.
- Remove the oil from the pipe end after the threading procedure and wrap it with Jute and Boss White or Teflon tape.
- Install the pipe to the screw fitting.
- Install the pipe as per approved shop drawings with provision to install the nozzles at location as indicated on the approved shop drawing.
- Install support near to the last bend of each nozzle location.
- All drops to 180 degrees nozzles require back-bracing in the opposite direction of the discharge.
- Ensure that there is no residuals present inside the pipe before installing the nozzles.
- Install the nozzles by tightening the nozzles at the last end of the pipe at location as identified on the approved shop drawings.
Testing & Commissioning of Fire Suppression System
- Pressure testing for the system should be done before installation of the nozzles.
- Air is used as the medium of pressure testing for Clean Agent System.
- Ensure that testing equipments /tools are ready .
- Ensure that system should be measured with calibrated pressure gauge installed at the lowest point.
- Ensure the pressure gauges are calibrated and valid calibration certificates available, issue calibration certificates to the consultants.
- Pressure shall be applied to the system by means of air compressor. The compressor discharge shall be connected to the system through a glove valve and recently calibrated pressure gauge of suitable range.
- After the test pressure is reached, the compressor shall be block off by closing the glove valve and the variations of pressure in the system monitored on the pressure gauge.
- Check the pipes, pipe joints and accessories for the leakage of air while pressuring and if any, attend the fault and rectify.
- Ensure all the leakages are arrested after the correction is made, the pressure test shall be repeated until a completely tight system is ensured and the testing procedure shall follows as:
- Pressure line at 40 psi for 10 minutes and at the end of 10 minutes, the pressure drop should not exceed 20 percent of the test pressure as per NPFA.
Pressure testing documentation shall be submitted along with inspection request for consultant /client approval.