Since its founding in 1917, the company has established itself as a leader in the design of high-efficiency systems for transporting abrasive materials for their customers in the power generation, biomass & Waste-to-Energy, pulp and paper, and other industries.  With more than a century of experience, A-S-H solutions are widely used across North America and select global markets offering after-sales support, spare parts, maintenance services, and system upgrades.

Allen-Sherman-Hoff history

1917

Three mechanical engineers, Frank Berry Allen, John Baker and Frank H. Dunbar form the Baker-Dunbar-Allen Company in Cleveland, Ohio. Their goal was to improve coal handling techniques for power plants. In 1921, Frank Allen left for Philadelphia, Pennsylvania, to form a new company with Max Sherman and Leigh Hoff. Together they formed the Allen-Sherman-Hoff Company (A-S-H) and subsequently purchased the equipment, drawings and patterns from the Baker-Dunbar-Allen Company.

1920 - 1929

Allen-Sherman-Hoff’s business initially consisted of the supply of cast iron hoppers for coal storage and the collection and conveyance of bottom ash below the boilers
 

1930 - 1949

The original arrangement was modified in the early 1930s when A-S-H develops the HYDROSEAL pump, designed to better handle the high abrasive wear of the ash. Its use allowed the collected ash to be carried through pipes at faster conveying rates and farther distance from the boiler.
A-S-H introduces the Hydrovac™ pneumatic vacuum conveying systems for the transport of fly ash to the sluices. A new line of fly ash components is developed to combat the wear of abrasive fly ash moving at high velocities. HYDROVACTOR® vacuum producers and steam jet exhausters provided the required vacuum-induced flows. The hydraulic bottom ash handling system, utilizing the HYDROSEAL pump, dominated the ash handling industry until the introduction of the jet pump which provided improved performance at a lower cost with reduced maintenance.

1950 - 1959

A-S-H introduces its complete line of HYDRO-EJECTOR jet pumps in 1952.

1960 - 1969

The Allen Family retained control of the company until 1963 when the assets of the ash handling group were purchased by the Baldwin-Lima-Hamilton Company and a new corporation named Allen-Sherman-Hoff, Inc. was formed. This new company operated first as a subsidiary, then as a division, of Ecolaire Incorporated.
 

1970 - 1979

Ecolaire establishes the offices of A-S-H in Malvern, Pennsylvania.
A-S-H successfully negotiates the technology transfer contract with the People’s Republic of China, establishing A-S-H’s dominance of the ash handling industry in the PRC. A-S-H was also awarded the two largest ash handling system contracts ever tendered at that time, both for Taiwan Power Company’s Taichung Station.
Allen-Sherman-Hoff advances its technology development in dilute-phase transport systems, pressure dense-phase transport systems and mechanical drag conveyors.

1987

Allen-Sherman-Hoff acquires HydroAsh from the L. B. Foster Company of Pittsburgh, Pennsylvania. At the time of this acquisition, HydroAsh had established itself as the third largest ash handling equipment supplier in the United States. Under Allen-Sherman-Hoff, the HydroAsh group targeted the industrial ash handling market, its strongest niche. Eventually the design strengths and products of HydroAsh were assimilated within A-S-H’s product offerings.
In late 1987, Ecolaire merges with Joy Manufacturing Company. A-S-H’s operations were combined with Western Precipitation (WP), another Joy unit, forming Joy Environmental Technologies, Inc. The product offerings of this new company included A-S-H’s ash handling equipment and WP’s air pollution control equipment.

1995

Anticipating a synergy with its highly successful sootblower and auxiliary boiler equipment business, Diamond Power Specialty Company (DPSC), part of The Babcock & Wilcox Company (B&W), acquires the assets of Joy Environmental.
Allen-Sherman-Hoff was established as a division of DPSC for the supply of traditional ash handling systems, equipment and parts, while the Western Precipitation air pollution control equipment was joined under B&W’s environmental technologies group.

2002

Diamond Power International, Inc. (DPII) acquires certain assets of the Beaumont Birch Co., establishing Allen-Sherman-Hoff as part of DPII’s ash handling division.

2016

As part of a company-wide strategy to integrate operations and emphasize its complete and broad power plant capabilities, B&W realigns the Allen-Sherman-Hoff operations under the B&W company brand, marketing all ash handling systems, products, parts and upgrades with the Allen-Sherman-Hoff (A-S-H) product brand.

2022
 

Recognizing the enduring value of the Allen‑Sherman‑Hoff brand and its close alignment with customer needs, B&W re‑establishes Allen‑Sherman‑Hoff as an independent business unit. This move strengthens customer focus, preserves specialized material‑handling expertise, and improves agility in delivering tailored solutions and lifecycle support.

2025

ANDRITZ strengthens boiler service business by acquiring Allen-Sherman-Hoff from US-based Babcock & Wilcox Enterprises, Inc. The acquisition supports ANDRITZ’s long-term strategy to grow its aftermarket and service business by offering customers complete lifecycle solutions and support. “We are excited to welcome Allen-Sherman-Hoff to the ANDRITZ family,” says Henrik Wikstedt, Senior Vice President, Recovery & Power Service division. “Their expertise in material handling complements our existing portfolio and enhances our ability to deliver integrated solutions and services for cleaner and more efficient boiler operations.”