Recording power meter - for mutisheave block and tackle cables esp in well boring

摘要

The work delivered by the cable in eg ton-km is computed by an analogue computer fed with inputs corresp. to the cable run-out and the cable tension as in parent patent, the cable run out being measured by a friction wheel in contact with the cheek of the winch or drum. Instead of electrical methods, the friction wheel drives hydraulic or pneumatic tachometer transmitter and the cable tension is also measured hydraulically or pneumatically. Operational safety in hazardous atmos. is obtd.