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The Crown Block is the fixed set of pulleys (called sheaves) located at the top of the derrick or mast, over which the drilling line is threaded. The companion blocks to these pulleys are the traveling blocks. By using two sets of blocks in this fashion, great mechanical advantage is gained, enabling the use of relatively small drilling line to hoist loads many times heavier than the cable could support as a single strand.

ALCO offers, supplies and stocks a variety of highly engineered Crown Blocks with one of the most complete offerings in the industry. We provide access to a comprehensive portfolio of various types of North American ALCO Manufactured & Internationally Manufactured Crown Blocks to meet each customer’s specific requirements from standard to highly tailor made solutions.

  • ALCO Crown Blocks are designed, manufactured and certified to API Spec 8C SR2 (-40) PSL 1
  • ALCO Crown Blocks are available in load-ratings from 50-ton (44,480daN) up to 500-ton (444,800 daN)
  • Current designs accommodate up to seven (7) sheaves
  • Custom designs are also available to suit your drilling-operation needs
  • North America and International Manufactured options

Types of ALCO Supplied Crown Blocks

ALCO supplies a large variety of Crown Blocks to meet your individual needs. We specialize but are not limited to the following:

  • Multiple Sheave Unites
  • Customer Engineered Designs
  • North American  Manufactured Options
  • API 8C Licensed Sheaves and Q1 In House Manufacturing

Contact our expert sales staff for pricing, availability and product specifications for the Crown Block right for your application at the link provided on this page

Features / Benefits

  • Design
    • All products designed, manufactured and certified for low temperature applications
    • Heavy-duty wireline guards
    • Secondary retention on all primary-load-path hardware components
    • Available with up to seven (7) sheaves
  • Side Plates
    • A514 steel side-plates allow for smaller overall dimensions with higher load-ratings
  • ALCO Sheaves
    • Forged one-piece sheaves with flame-hardened wireline grooves
    • Extra-heavy groove area to allow multiple re-cuts