Elevator compensation chains

Why a shaft needs a compensation chain

The elevator compensation chain is a device for load compensation in the “car–counterweight” system. It is installed in the shaft, connecting the base of the car and the counterweight, and balances the weight load from the traction rope: at the lower and upper floors the rope weight falling on the different sides of the system differs greatly. In buildings with a lifting height of 30 m or more, such balancing is necessary.

Without compensation the car and the counterweight are balanced only in the middle part of the shaft; the compensation chain equalises the system along the whole height. In our catalog such chains come in two versions — rubberised and in a PVC sheath; the weight by gauge is given in the table.

How it differs from a traction chain

A traction chain transmits the drive force: it operates in a mechanism, usually on a sprocket, and its characteristics — pitch, calibration, strength — are subordinated to that work. A compensation chain does not transmit the drive force: its task is to balance the system. Therefore the main parameter for selection is not “strength like a traction chain” but the weight per metre and the version that provide the required compensation.

At the same time the chain works under loads, and selection for a specific elevator installation is important: the wrong choice leads to a dynamic imbalance of the system. The sets of standardised loads for elevator and traction chains are different — they cannot be compared “head-on”.

Sheath and protective coatings

A compensation chain usually has a construction wrapped in a PVC-rubber composite material: the sheath reduces the noise from the chain's operation and ensures smooth running of the elevator. For additional noise reduction in the shaft, chain stabilisers are used.

The metal core is protected from corrosion by a coating: zinc plating is the standard measure for damp conditions, more details in the article Chain zinc plating. The sheath material, coating and gauge are agreed when ordering for a specific installation.

How the required weight is determined

The compensation weight is determined from the weight of the traction rope minus the weight of the travelling cable chain; then the weight per metre of the compensation chain is selected by the manufacturer's gauges. Reference points for our range (from the “Weight per 1 m of chain” table in the catalog):

• rubberised chains Ø7–Ø11 mm — about 1.23–2.85 kg/m;
• plastic-wrapped chains Ø5.5–Ø7 mm — about 1.12–1.88 kg/m.

The weight per metre is the key parameter: it determines how fully the chain compensates the imbalance. The exact calculation and the permissible version options are agreed when ordering.

What to look at when replacing

• Installation parameters: lifting height, required compensation, fastening method — the length and weight of the chain depend on them.
• Version: rubberised chain or chain in a PVC sheath; for damp conditions, discuss the protective coating in advance.
• The assembly: the condition of the fastenings and stabilisers is checked by the specialised organisation servicing the elevator.

The criteria for taking the chain out of service and the replacement procedure are established by the servicing organisation under its own regulations — these norms are outside the plant's scope, and we do not publish them. The selection of a chain for your installation and the replacement decision are made together with an elevator equipment specialist and our manager. The admission and certification of elevator components are handled by the specialised organisation — we do not make such claims.

Send the parameters — we will select

State the lifting height and the required compensation (or the traction rope data), the desired version and the quantity. Send the data to a manager — we will select chains by our gauges and calculate for your installation.