Technical Guide

1. Driving System

(1) Traction Method

Two types of driving systems for rope-type elevators include drum method (winding-drum type elevator) and traction method (traction type elevator). The traction method comprises the following:

(a) Geared

Motor rotation (speed) is reduced, by 1/10th using a speed reducer, equipped with worm or helical gears, and transmitted to the traction, sheave of the traction machine.

(b) Gearless

The traction sheave is connected, directly to the shaft of the traction, motor, and the motor rotation, (speed) is transmitted directly to, the traction sheave without any intermediate gearing.

(2) Hydraulic Type

With the hydraulic type driving system, the hydraulic power unit forces oil into the hydraulic jack (a combined plunger and cylinder) and the plunger pushes the car upwards using energy stored in the oil under pressure. The car descends automatically as the oil returns to the cylinder along the same route. Car-and-jack combinations are described in the table below.

Following the introduction of the machine-room-less traction method elevator, production figures for hydraulic-type elevators have been falling each year.

(a) Direct Acting (direct plunger driving)

Plunger pushes up car directly at a 1:1 ratio of plunger-to-car movement.

1. Driving System

(1) Traction Method

Two types of driving systems for rope-type elevators include drum method (winding-drum type elevator) and traction method (traction type elevator). The traction method comprises the following:

(a) Geared

Motor rotation (speed) is reduced by 1/10th using a speed reduce,equipped with worm or helical gears, and transmitted to the traction, sheave of the traction machine.

(b) Gearless

The traction sheave is connected, directly to the shaft of the traction, motor, and the motor rotation (speed) is transmitted directly to, the traction sheave without any, intermediate gearing.

(2) Hydraulic Type

With the hydraulic type driving system, the hydraulic power unit forces oil into the hydraulic jack (a combined plunger and cylinder) and the plunger pushes the car upwards using energy stored in the oil under pressure. The car descends automatically as the oil returns to the cylinder along the same route. Car-and-jack combinations are described in the table below.

Following the introduction of the machine-room-less traction method elevator, production figures for hydraulic-type elevators have been falling each year.

(a) Direct Acting (direct plunger driving)

Plunger pushes up car directly at a 1:1 ratio of plunger-to-car movement.

(b) Indirect Acting (suspended type or roped hydraulic drive)

Plunger is connected to car by roping, using a deflector and suspension sheave, moves car up and down at a, 1:2 ratio of plunger-to-car movement.

2. Roping Systems

There are various roping systems as shown in the figures and tables below. Although they vary according to the traction speed, rated load, and other factors, roping should be kept as simple as possible. Reducing the number of deflectors and suspension sheaves improves longevity and efficiency of the ropes.

With 2:1 or 4:1 roping, car speed is reduced to 1/2 or 1/4, respectively, of the rope speed, because suspension sheaves are provided above (or below) the car and counterweight, and both ends of the rope are attached to the machine room beams. With these roping systems, loads on the rope is reduced to 1/2 or 1/4 as well, hence the diameter and number of ropes can be reduced.

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Exhibition 2011

Updates!

Workshop on pumping technology by Turkish Experts has been accomplished at Zarahh Group's premises.

Sales Training has been started to the Sales force.

Innovative technology is being using for Bore wash.

Service and Maintenance of submersible pumps & Bore on monthly contract basis,

Water Treatment Plant at Ethopia is in underprocess.

Irrigation system & wastewater treatment plant has been accomplished at PAKISTAN AIR FORCE 'S golf club karachi.

PANI package has been offered.