Cranemaster is a specialist provider of shock absorbers and heave compensators for offshore crane and lifting operations. Our heave compensators and shock absorbers compensate forces and motions directly at the load or hook level, securing offshore lifting operations and enabling clients to work in higher waves. We have a large fleet of Cranemaster® units for lifts up to 1400 ton ready for rental, located in Norway or at our local representatives.
Our competent engineering team is eager to solve any challenge you have related to dynamics or motions, using our existing technology or through development of tailor made solutions. Orcaflex analysis of lifting operations are carried out by our analysis team.
Pioneers in offshore lifting
Since its foundation in 1983, Ernst-B. Johansen AS (the official company name) has become a market leader in the field of shock absorption and passive heave compensation systems for offshore lifting operations.
The founder Ernst B. Johansen perceived a gap in the market following an increasing number of lifting incidents in the North Sea. With hard work and dedication he made the company a success in its niche.
Today – through its marketing brand Cranemaster – Ernst-B. Johnansen AS works closely with the world’s leading offshore contractors.
Continous product development
Innovation and continuous product development is at the heart of the Cranemaster philosophy. Since the first units were developed in the early 1980’s, they have been continuously improved and refined, with features such as Lock & Release, Quick Lift and Depth Compensation.
Today our advanced systems are equipped with valves, sensors and PLS automatically optimizing the properties of the units from lift-off to landing.
Our new and modern facilities allows us to carry out various tests and simulations and even our largest units can be handled in-house.
Worldwide Cranemaster Network
Local stock, service and solution engineers through trusted partners worldwide. Feel free to contact them directly.
News from Cranemaster
Order & Delivery
Cranemaster have the world’s largest fleet of rental units ready for immediate mobilization. Combined with rapid response from quotation through to delivery ensures our customers short lead times and on-time delivery.
The Cranemaster® units can be shipped by road, sea or air. Shipment is usually done in open containers or on pallets. If air freighted, the units can not be pressurized in advance. The units are delivered with shackles on both ends (heavy duty or wide body), hoses, manometer, gas filling set, adapter for Nitrogen bottles and valid certificates. If required, a Cranemaster service technician can assist with mobilization, give sessions on site for the operational crew and/or assist offshore during the lifting operation.
Dimensions and weight for each unit is given in Product Datasheets and can be requested either through our Inquiry Form or from our Rental Fleet overview. Our sales engineers are happy to help you find the best solution for your requirements.
A Cranemaster passive heave compensator (PHC) is a spring-damper system based on gas pressure and hydraulic fluid. As it is self contained, no external connections of hoses or wires are required.
Yes, utilization of a Cranemaster shock absorber will have an effect on peak loads for lifts in air. When there is relative motion between a lifted object and the boom tip, a snap load will occur. As a consequence, the dynamic amplification factor (DAF) will increase and potentially lead to unacceptable high peak loads. A Cranemaster unit will work as a shock absorber, efficiently removing these snap loads, and as a result reduce DAF and improve safety. Typically, this will enable you to conduct such lifts in higher sea states, and thereby increasing the operational weather window.
No, as Cranemaster passive heave compensators rely on external forces to reduce motion, they will have no impact on the movements of free hanging objects in air.
Both Active Heave Compensation (AHC) and Passive Heave Compensation (PHC) are techniques used on lifting equipment to reduce the influence of waves upon offshore operations. AHC differs from PHC by having a control system that actively compensates for any movement using external energy. Passive systems reacts to external forces without additional energy to control the motion.
Yes, Cranemaster units will work perfectly together with AHC that responds to inputs from an accelerometer.
Yes, Cranemaster heave compensators are designed to instantly respond to its surroundings, take up slack wire and reduce dynamic loads.
Cranemaster units are certified for operations down to 3000 meter. As of today Cranemaster units has been used at close to 3000 meter water depth.