How much LPG and power do Rajkot investment casting units use, and what goes in a buyer's carbon figure?

Rajkot's 110 or so investment casting units used 184 million kWh, 2,610 t of LPG and 8.9 million scm of gas in 2014 to 15 for about 48,000 t of castings. That is about 3 t CO2 per tonne from energy alone, mostly power. A buyer's figure adds the alloy you melt.

The cluster in TERI's 2015 profile

• About 110 units: about 10 making 70 tonnes a month, most around 40, and about 25 around 10.
• About 160 tonnes of castings a day, roughly 48,000 tonnes a year, in stainless steel, carbon steel and brass, mainly for pumps, valves, auto and textile machinery.
• About 70% of units bake shells and heat treat on PNG; the rest on LPG.
• Melting and shell baking take about 30% of a unit's energy each; cold room air conditioning, compressors and heat treatment take most of the rest.

Why the per-tonne figure is so high

• Yield is only 40 to 50%: gates, runners and rejects get melted again, so melting takes about 2,000 kWh per tonne of good castings although molten metal needs only 600 to 850.
• Ladles are tapped in small lots as shells come ready, so furnaces hold metal hot for 45 to 100 minutes.
• Wax rooms run at 22 to 24 degrees C all day: a typical unit has 3 or 4 chillers of about 50 TR.
• Units on PNG average about 0.55 toe per tonne of good castings; units on LPG about 0.72.

The cluster's CO2 on today's factors

• Electricity: 184 million kWh x 0.675 kg = 124,200 t.
• Gas: 8.9 million scm x 2.05 kg = 18,250 t.
• LPG: 2,610 t x 2.98 = 7,780 t.
• Total about 150,200 t on 48,000 t of castings: about 3.1 t CO2 per tonne, 83% of it from power. This is energy only, before the alloy.

What a pump or valve buyer's figure needs

1. Your energy per tonne of good castings, as above, from twelve months of bills and dispatch weights.
2. The metal: kg of alloy melted per kg shipped, with a figure per kg for each grade, such as 304 or 316 stainless, from your bar or scrap supplier.
3. Wax, ceramic slurry and stucco if the buyer asks for a full product footprint.
4. Most investment castings ship as pump, valve or machine parts or under 7325, outside CBAM today, so this is a buyer request, not a customs filing. Confirm the CN code.

Worked example: TERI's typical 500 t a year unit on PNG

• Power: 1,900,000 kWh x 0.675 = 1,283 t CO2
• Shell baking and heat treatment: 100 toe x 41.868 GJ = 4,187 GJ x 56.1 kg = 235 t
• Total: 1,518 t for 500 t of good castings
• Energy per tonne: about 3.0 t CO2, before the alloy
• Raise yield from 45% to 55% and melting power per good tonne falls by about a fifth

Energy use is TERI's typical unit. Gas uses the IPCC natural gas default per GJ. The yield line assumes melting power scales with metal melted per good tonne: 45 / 55 = 0.82.

What Senseible does here

Send Senseible your PGVCL bills and gas or LPG invoices and it builds the monthly energy and CO2 records; divided by the tonnes you dispatched, that is the energy per tonne a buyer asks for. The alloy figures come from your metal suppliers and sit beside it.

• Supplier evidence for your buyers
• Investment casting footprint per kg
• Are pumps and valves covered by CBAM
• Emission factor for purchased stainless

Sources: TERI, Cluster profile: Rajkot investment castings foundries (SAMEEEKSHA, 2015; data 2014 to 15), IPCC 2006 Guidelines, Volume 2 Energy, Tables 1.2 and 1.4, CEA CO2 Baseline Database, version 22.0, CBAM Regulation (EU) 2023/956, consolidated, Annex I

Last reviewed 2026-10-30. TERI data is from 2014 to 15. Update if a newer Rajkot investment casting profile is published.