Form work


After welding/installing the anchors, you must fill the castable mortar.But to fill the castable mortar,you require a mould to hold it.That mould is called as form work or shuttering or casting.

Qualities of a good shuttering

·         It must never allow water leakage.

·         It must withstand the castable pressure without bulging etc.,

·         Use only mild steel or stainless steel or polished plywood only for casting jobs.

·   Use only thick shuttering material as thin shuttering material bends due to castable pressure. 

·         The shuttering material to be clean without any dirt.

·         Never use shuttering material which has crack,bend or any damage.



 (castable form work image)
                          

Precautions

·         Never remove shuttering unless it was confirm that the mortar got dry.

·         Paint grease or any oil on the shuttering surface(internally on the phase which contacts the mortar) for easy removal of shuttering works.This paint of oil or grease avoids moisture loss from the mortar to atmosphere. 

·         Never do any shuttering work in a hurry.


Castable mixing & preperation

Are you thinking that the castable preperation is a paramount complex method?
If you think its yes,then you are wrong. Because any castable preperation is simple and basic method.Lets see how.

Follow the following points for efficient castable mixing and preperation

·         Keep the work area and its surroundings clean and dry to avoid contamination of castables by outside foreign material.

·         Mixer equipments,other equipments & tools to be clean.

 Arrange and keep ready all necessary equipments tools,castables,manpower,welding systems and accessories etc.,

·         Lubricate the mixer machine parts and bearings to avoid struck up of mixer machine in the middle of the work.

·         To avoid such problems,its recommended to service mixer machine at required intervals.Also run the mixer machine daily for a few minutes to avoid bearing jam.

·         Perodical inspection of mixer machine was recommended.

·   Check the belt condition of the mixer machine to avoid any slippage which causes improper mixing.

·         If any abnormal sound from mixer machine,it may be due to belt too looseness or it may be some other problem.So stop the machine and rectify it.

·    Clean the mixer machine pan to avoid contamination of other materials with castable while mixing.

·  Shift the required castable/refractory to near by work site at required quantity.Castable mixing and work area to be very near to each other for easy and quick transportation and to avoid any delay.

·    Ensure that the required anchors and shuttering works are completed as per requirement.

·   Never start any castable mixing work without completion of the above said works very strictly.

Ensure that the castable/refractory life has not expired or not near to expiry date. 

What is the efficient method to mix castables?


Its very easy and time saving to mix castable by shovels,but it was the correct method.shovel mixing leads to improper mixing resulting in castable life failure,cracking of castables etc.,

So never use shovels for castable mixing.
Use only paddle type mixer machines for castable mixing which provides sound mixing.


(castable mixer machine) 

How to use paddle type mixer for castable mixing?


Just follow the basic procedure to get required castable mixing.

·        Connect the electrical supply and run the machine for few seconds to check for any obstruction,to check for any hitting of mixer blades with pan walls internally etc.,

·   Load the required quantity of castable into the mixer pan while mixer is in running condition.

·      Never load the castable while mixer is in stopped condition as it causes mixer machine motor overload while starting.

·    The castable quantity to be loaded into the mixer machine is to be strictly as per supplier specification only.

·         Run the mixer machine for few seconds with castable in dry condition (without adding water) for even and good distribution of castable inside the mixer which facilitates good mixing.

·     Add required quantity of water for castable mixing.The water quality to be ice cooled & drinking type.

1.  Ice cooled water ie., add ice to water to suppress the heat due to castable + water reaction.(Heat causes castable cracking,low castable life etc.,)

2.   Drinking water ie., any contaminated water affects the castable + water reaction which affects castable life and causes cracking etc.,

· The quantity of water to be strictly as per castable supplier recommendation only.

·         If required you can add slightly more water than the supplier recommendation, but not less than supplier recommendation as less water is always danger of causing clogging of castables,cracking,quick setting of castables before strengthening or application etc., 

·   Spray the water using watering can circumferentially around inside the pan mixer while mixer machine is running for good castable mixing.






·       Never pour the water inside the mixer machine at one place as it causes castable clogging.Just spray it continously as per requirement.

The water level in any castable mix can be predicted by Ball in hand test.  

What is ball in hand test?
Take little quantity of castable mix and mould it in a small ball form.Now throw/toss the castable ball upto one feet (just approximately) and catch the ball in your one hand.

                
If the ball remains stiff in its shape,it shows that water level in the castable mix is correct.

If the ball cracks or breaks,it indicates that water level is low in the castable mix.

If the ball material drains out between the finger of your hand, then it means the water level in the castable mix is high.

      
   

 (paddle castable mixer) 


Never use shovels for castable mixing at any cost.
·     Initially spray 3/4th of the required water quantity.but if required spray more water for good mixing consistency.

·       Never mix for more than 3 minutes to 4 minutes as over mixing creates castable setting and castable loses its strength.

·     Always mix castables in smaller batches to avoid wastage and mixed castable mortar waiting time.

Mixed castable mortar must not wait for work for more than 15 minutes or else the castable loses  it strength.