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?Road, rail, port and power projects are boosting the market. In the future, we expect real estate projects to add momentum to the industry,? says V G Sakthikumar, Managing Director, Schwing Stetter Sales and Services Pvt Ltd, and Chairman of Mechanisation Committee, Builders Association of India (BAI). ?Infrastructure projects like roads, flyovers, power plants and the general industry are driving demand presently,? says Sudhakar Waggh, Country Manager Service, Aquarius Engineers. ?In the future, building construction could further boost the market for concrete pumps?

?Real estate, road, power plant and other civil construction projects are driving demand for ready mix concrete. In the future, we expect heavy industry, flyover, airport, metro rail, dock, railway bridge, dam, tunnel and canal projects to further boost the RMC market,? opines Naresh Aggarwal, Managing Director, Bharat Cements, which supplies concrete in and around its cement plant in Purulia, West Bengal.

Popular concrete pumps in India
The Indian concrete pump market is distinct from mature markets. Whereas in mature markets like the US, Europe and even China, truck mounted pumps are the main product lines, in India, stationary pumps with an hourly output of 40-90 cu m dominate the market. Stationary pumps are used for high-rise buildings as well as by RMC companies offering job site services.

?Stationary pumps are more in demand as they are more affordable and occupy less space, a key objective at space-constrained sites. Demand for truck-mounted boom pumps is comparatively less,?explains Waggh.

Industry sources peg the demand for stationary pumps at about 1,500/year whereas the market for truck mounted boom pumps is below 100 units/year.

In the truck-mounted boom pump segment, customers who aim to complete jobs in the lowest possible time are opting for the S43SX, S36X [larger] models, says Sakthikumar. ?But during slowdowns when time is not critical, customers prefer smaller equipment like the S17, S20 which pose a lower investment risk,? he says.

Equipment evolution
The need to cater to demand for sturdier and wear-resistant pumps is a strong driver of pump innovations and the introduction of new models. Schwing Stetter has customised its four Indian boom pump models, S17, S20, S36X and S43SX to cope with variations in the quality of raw materials across the country.

?Raw material directly influences the wear and tear of concrete pump parts and thus the operating costs, and the overall pump performance. We have developed parts and pipes for high wear and tear applications and a twin circuit system to facilitate the pumping of stiff concrete,? says Sakthikumar.

Another Schwing innovation addresses a constraint of real estate developers - working in tight spaces. Schwing has launched the ?EASY? system whereby customers can stabilise the boom by extending just two outriggers instead of all four, and still gain a coverage area of 141o.

Universal has responded to growing demand for pumps for high-rise buildings, flyovers, dam projects, wind turbine foundations and other infrastructure projects with Zoomlion concrete pumps featuring a hydraulic system with double pumps and double circuits.

?Driving the pumping system and distribution system with two independent pumps - instead of one as in single pump double circuit models - allows a more stable oil flow rate to the pumping unit,? explains Ranjit More, Managing Director, Universal
Construction Machinery & Equipment Ltd. Additionally, a single operator can easily change the concrete piston in these pumps without any special tools in 15 minutes. Extra stroke in the hydraulic cylinder allows the piston to extend from the concrete cylinder, enabling horizontal discharge up to 430 m and vertical discharge up to 120 m.

Extra features for extra power and versatility is taking the concrete pump industry to new highs.

Overcoming Challenges to Create a World Record in Long Distance Concrete Pumping

• Hindustan Construction Company (HCC) created a world record in long distance concrete pumping at the 100 MW Sianj Hydroelectric Power Project site, a Himachal Pradesh Power Corporation Limited project. HCC pumped concrete 2,432 m horizontally during the construction of a 6 km tunnel with a finished diameter of 3.85 m and average lining thickness of 0.25 m. The previous record was of 2,015 m in France. The power project lies on the river Sianj in Kullu district.
• ?Long distance pumping made sense in this project because of the relatively small diameter and the length of the tunnel. Vehicular movement and crossing becomes challenging in a congested working space. Controlling the temperature and humidity and providing adequate ventilation becomes challenging as the tunnel length increases,? says Arun Karambelkar, President and CEO, HCC E&C.

Long distance concrete pumping brought along its own challenges, such as the selection of the concrete pump and pipeline, the layout of the concrete conveying pipeline, the selection and quality control of concrete materials and dealing with diverse climatic conditions and safety. Here?s how HCC dealt with these matters:

• HCC chose Schwing?s SP 4800 model for the job. Based on the required flow rates, productivity and pressure considerations, HCC choose a 150 mm internal diameter pipeline. To sustain high pumping pressure, a pipeline of variable thickness (10 mm thick near the pump, then 7 mm thick) was selected.
• The pipeline layout was designed to be efficient for installation and maintenance, cost-effective, with least pressure drops due to bends and less wear of pipeline. It was installed on concrete blocks for stability; adequate clamping arrangements were made for jerk-free operations, especially for the close-to pump pipeline.
• HCC closely controlled the quality of the crushed aggregates to control the quality and consistency of concrete. HCC optimised the aggregate crushing plant for optimal performance. Diverse climatic conditions (temperatures ranging from 5?C to 35?C) also impacted the concrete mix, as did the required placement rates vis-a-vis the available transit mixers of 4 cu m capacity and two CP 30 batching plants. A specially formulated chemical admixture (BASF SKY8787) was used to make self-compacting concrete (SCC) with varying retention periods (4-12 h) and setting times ranging from 18 hours to 24 hours.

Choice of Equipment for Pumping Huge Quantities of Concrete Project:

Oncology Radiation Chamber Room, Hiranadani Hospital,

Mumbai By: Lafarge India Ltd.

Assignment: To retrofit a bunker in the basement by pouring concrete in an RCC wall covered by a one metre thick RCC slab beneath the existing basement RCC slab. Key challenges: 1. Concrete had to be poured without disturbing the operations of the hospital. 2. The concrete had to be poured with uniform density to comply with stringent Atomic Energy Regulatory Board standards.

Method and material: For the final slab, concrete was poured through core cuts from the ground floor. To achieve the required density and uniform spreading, Lafarge used Agilia? self-compacting and self-levelling concrete with a compressive strength of 40 MPa; around 700 cu m of concrete in all.

?Lafarge opted to use a Schwing Stetter concrete pump SP1800, a model that is usually deployed wherever vast quantities of concrete have to be pumped horizontally or vertically. It has a maximum output of 73 cu m/hour with a concrete pressure of 108 bar,? says Frederic Guimbal, Chief of RMX and Aggregates, Lafarge India Ltd.

Desirable Features in a Concrete Pump
Ranjit More, Managing Director, Universal Construction Machinery & Equipment Ltd elucidates desirable features in a concrete pump, and the reasons therefore:

Intelligent control systems: Control systems enable easy operation and render the electrical system highly reliable.
Well-designed S valve: To ensure the smooth flow of concrete
Large angle fluent hopper design: To allow high suction capacity and minimise the feed accumulation area
Fine filtration device: To treat the hydraulic oil and extend the lifetime of the hydraulic components and the oil change interval. Driving the pumping system and distribution system with two independent pumps allows a more stable oil flow rate.
- Ranjit More, Managing Director, Universal Construction Machinery & Equipment Ltd.

Stationary pumps are more in demand as they are more affordable and occupy less space.
- Sudhakar Waggh Country Manager Service, Aquarius Engineers

Long distance pumping made sense for our Sianj Hydroelectric Power Project because of the relatively small tunnel diameter and length.
- Arun Karambelkar President and CEO, HCC E&C

Choice of Equipment for Vertical Pumping

• Project: Lodha Washington House project at Altamount Road, Mumbai
• Challenge: Pumping concrete 160 m high
• Choice of pump: Aquarius 1407D HR pump
• We evaluated the height to which we had to pump the specified grade of concrete to decide on a pump. To choose a provider, we evaluated the cost of the options and availability of spares and service,? says Mahesh Gawade, P&M Department, Capacite Infraprojects Pvt. Ltd.
• We chose Aquarius for this project because it offered us a cost saving of 10 per cent to 15 per cent, which is more or less the margin on projects, so it?s very considerable. Also, Aquarius offered us 24x7 support services.?

Real estate, road, power plant and other civil construction projects are driving RMC demand.
- Naresh Aggarwal Managing Director, Bharat Cements.

Schwing Stetter concrete pump SP1800 is usually deployed wherever vast quantities of concrete have to be pumped.
- Frederic Guimbal Chief of RMX and Aggregates, Lafarge India Ltd.

Concrete Pump Commissioned 1 km Underground

• Site: Hindustan Zinc Ltd operated a zinc mine in Rampura Agucha, Rajasthan, the world?s largest zinc mine and the third largest open-pit mine
• Project: Construction of vertical and horizontal tunnel for underground mining
• Timeline: February 2016
• Contractor: Shaft Sinkers (Pty) Ltd, Mauritius
• Challenge: Deep digging faces challenges of water flooding inside the tunnel, safety issues, precision issues, etc., which call for special arrangements such as concrete grade selection, safety design arrangements, improved equipment specifications, voltage stabilisation, etc.
• Solution: Aquarius 1003E electrically driven concrete pump
• Customisation: ?We made special provisions in the control panel, pump settings, base frame, etc., to meet the stringent site requirements,? explains Sudhakar Waggh, Country Manager Service, Aquarius Engineers. ?The pump is installed at a depth of nearly 1 km below the ground level. At different levels, several horizontal tunnels branch off from the vertical tunnel, making substations. The pump supplied concrete over a horizontal distance of 30 m to 40 m, to the hopper of the shot concrete machine for application on the tunnel walls.?

Aquarius offered us a considerable cost saving of 10-15 per cent.

- Mahesh Gawade P&M Department, Capacite Infraprojects Pvt. Ltd.

Customers who aim at completing jobs fast are opting for larger truck-mounted boom pumps.

-V G Sakthikumar Managing Director, Schwing Stetter Sales and Services Pvt Ltd, and Chairman of Mechanisation Committee, BAI