Tunnel Logo 1 1940s Tunnel Brand
Tunnel Logo 3 Big T Brand used from the late 1960s


  • Grid reference: SJ29146210
  • x=329137
  • y=362102
  • 53°9'5"N; 3°3'34"W
  • Civil Parish: Buckley (Mold), Flintshire: a small part of the new plant is in the parish of Hope

Clinker manufacture operational: 1949 to date

Approximate clinker production to 2015: 31 million tonnes (13th)

Raw materials:

  • Carboniferous Limestone (above - Cefn Mawr Limestone Formation: 326-331 Ma - below - Loggerheads Limestone Formation: 331-335 Ma) by road (12 km) from Cefn Mawr quarry at 319900,363400: Mold, Flintshire
  • Coal measures shale and colliery waste by road (11 km) from the Llay Main colliery tip at 332300,356200: Llay, Denbighshire. The tip of Bersham Colliery (331200,348100: 20 km) containing 6 million tonnes is next up.
  • Superficial sand from Hope and Bodfari


  • 1949-1968 Tunnel Portland Cement Company Ltd
  • 1968-1986 Tunnel Cement Ltd
  • 1986-2009 Castle Cement Ltd (RTZ to 1989, Scancem to 1999, HeidelbergCement to 2009)
  • 2009 to date Hanson Cement UK (HeidelbergCement)

The plant was one of several post-war projects that were somewhat delayed by the economic circumstances of the late 1940s: it was originally scheduled for start up in 1947. It was the last green-field plant location to be remote from both raw materials and its position seems to have been predicated by the rules of the then-existing pricing cartel. Even water was not available on site: it was pumped from an artesian well 8 km away. Both raw materials are brought by rather arduous trips on minor roads through a semi-urban area. The use of colliery waste, with a potential fuel saving, was not new: it had been employed at Cousland much earlier. Despite the obvious suitability of dry process, FLS were uninterested in this, and the plant used standard wet process as previously installed by them at many other hard-rock sites such as Hope, Ketton, Drogheda, Limerick and Ribblesdale. By the 1960s, however, they had started to develop “long dry” kilns, and A3 became a successful first venture in Britain. The carbonaceous rawmix made it peculiarly appropriate in this instance. It had a long service life.

The need to maintain capacity while getting rid of the wet kilns necessitated its replacement with the highly-efficient A4, which for the first time allowed full utilization of the potential heat content of the raw material.

The plant is on the Wrexham to Connah’s Quay branch railway and could use this initially for shale movement (from Llay Main’s siding when it still operated) as well as coal and despatch. Now only coal arrives by rail, and the plant transport is nearly all by road. The A55, 3 km away, gives rapid access to the motorway network.

Please contact me with any relevant information or corrections. I am particularly interested in firmer dates and statistics.

Note: technical information on currently operational plants is ✄withheld in the public version of the site at present, except where already published (see references).


  • For the wet process, two 675 kW ball mills, in closed circuit with centrifugal separators.
  • For the long dry kiln, one 1125 kW ball mill with drying air supplied by an oil fired furnace.
  • For the precalciner, ✄..

Four rotary kilns were installed:

Kiln A1

Supplier: FLS
Operated: 4/1950-1991, 1995-2005
Process: Wet
Location: Hot end (cooler ports) 329218,362115: Cold end 329125,362147: hot end enclosed
Dimensions (from cooler ports): Metric

  • 1950-1966 98.00 × 3.000BC / 3.450D
  • 1966-2005 98.00 × 3.300B / 3.000C / 3.450D

Rotation (viewed from firing end): clockwise
Slope: ?
Speed: ?
Drive: ?
Kiln profile (from cooler ports): -3000×3300: 34000×3300: 35750×3000: 62750×3000: 65000×3450: 97250×3450: 97250×3000: 98000×3000: tyres at 3000, 32000, 59000, 86000: turning gear at 56000: dust return at 61000.
Cooler: Unax planetary 10×6.30×1.400
Fuel: 1950-1970, 1975-2005 Coal: 1970-1975 oil
Coal Mill: indirect: 410 kW Tirax ball-mill common to A1 and A2 with oil-fired drying air
Typical Output: 1950-1966 415 t/d: 1966-2005 420 t/d
Typical Heat Consumption: 1950-1956 7.10 MJ/kg: 1957-1966 6.75 MJ/kg: 1966-2005 5.70 MJ/kg

Kiln A2

Operated: 12/1949-1991, 1995-2005
Location: Hot end (cooler ports) 329214,362104: Cold end 329122,362137: hot end enclosed
Dimensions (from cooler ports): Metric 98.00 × 3.000BC / 3.450D
Kiln profile (from cooler ports): -3000×3000: 62750×3000: 65000×3450: 97250×3450: 97250×3000: 98000×3000: tyres at 3000, 32000, 59000, 86000: turning gear at 56000: dust return at 61000.
Cooler: Unax planetary 10×6.30×1.200
Typical Output: 415 t/d
Typical Heat Consumption: 1949-1956 7.10 MJ/kg: 1957-1966 6.75 MJ/kg: 1966-2005 5.60 MJ/kg
Identical in all other respects to A1

Kiln A3

Supplier: FLS
Operated: 1966-3/3/2005
Process: Long dry
Location: Hot end (cooler ports) 329203,362087: Cold end 329083,362129: hot end enclosed
Dimensions (from cooler ports): Metric 128.00 × 4.150BC / 4.550D
Rotation (viewed from firing end): anticlockwise
Slope: ?
Speed: ?
Drive: ?
Kiln profile (from cooler ports): -3300×4150: 85000×4150: 88000×4550: 128000×4550: tyres at 3500, 34500, 74000, 113500: turning gear at 69000.
Cooler: Unax planetary 10×13.00×1.600
Fuel: 1966-1970, 1975-2005 Coal: 1970-1975 Oil
Coal Mill: indirect: Tirax ball-mill
Typical Output: 930 t/d
Typical Heat Consumption: 3.95 MJ/kg

Kiln A4

Supplier: FLS
Operated: 26/07/2005 to date
Process: air-separate precalciner: details ✄
Location: hot end 329138,362045: cold end 329076,362067: unenclosed
Dimensions: ✄
Rotation (viewed from firing end): anti-clockwise
Slope: ?
Speed: ?
Drive: ?
Kiln profile: ✄
Cooler: grate: details ✄
Fuel: ✄
Coal mill: ✄
Exhaust: ✄
Typical Output: ✄
Typical Heat Consumption: ✄

Sources: Jackson, pp 248, 291: Tunnel Cement (brochure), Tunnel Portland Cement Co., Ltd., 1950: Mervyn E. Foulkes, “The History of Cement Manufacture at Padeswood, North-east Wales” in Magazine of the Buckley Society, 28, 2004: Mervyn Foulkes also produced a video: A History of Cement Making at Padeswood Works in North Wales, Knew Productions, 2006 - the motivations for the production of this video were essentially the motivations for making this website - it is highly recommended.