How do I select the right V-belt cross-section?

V-belt cross-section is selected based on design power (power × service factor) and the speed of the faster shaft. Use selection charts: Z/SPZ for up to ~4 kW, A/SPA for ~2-20 kW, B/SPB for ~5-60 kW, C/SPC for ~15-150 kW, D for ~50-500 kW.

What is the difference between classical and narrow V-belts?

Classical V-belts (Z, A, B, C, D) have a wider profile. Narrow V-belts (SPZ, SPA, SPB, SPC) transmit more power per belt and per unit width. Narrow belts are preferred for new designs due to higher power density and efficiency.

How do I calculate the number of belts needed?

Number of belts = Design Power / (Power per belt × Correction factors). Correction factors include wrap angle factor (C1), belt length factor (C3), and number-of-belts factor. Round up to the nearest whole number.

What service factors apply to V-belt drives?

Service factors for V-belts: 1.0-1.2 for uniform loads (fans, pumps), 1.1-1.3 for light shocks, 1.2-1.4 for moderate shocks, 1.3-1.8 for heavy shocks. Multiply by 1.2 for more than 10 hours/day operation.

What is the maximum recommended V-belt speed?

Maximum recommended belt speed: 25-30 m/s for classical V-belts, up to 40 m/s for narrow V-belts. Above these speeds, centrifugal forces significantly reduce belt capacity and special high-speed belts should be used.

免費工程工具 #088

V 型皮帶選型計算器

選擇 V 帶截面並計算所需皮帶數量。皮帶剖面依據 ISO 4184；功率額定值基於典型製造商型錄資料。輸入功率、轉速、服務係數及滑輪直徑。

ISO 4184 剖面 Z/A/B/C/D SPZ/SPA/SPB/SPC

功率 (kW)

較高的軸轉速 (RPM)

服務係數

小皮帶輪直徑 (mm)

皮帶剖面

速比 (D₂/D₁)

快速預設

結果

所需皮帶數量

—

設計功率 (P_d)

—

單條皮帶功率 (P_b)

—

建議剖面

—

皮帶線速度

—

設計功率

皮帶數量

其中 C₁ 為包角係數，C₃ 為皮帶長度係數，P_b 為單條皮帶的基本功率額定值。

V 帶剖面選擇指南

輪廓	類型	頂寬	功率範圍（典型）	最小皮帶輪 ⌀
Z	標準型	10 mm	0.2 – 4 kW	50 mm
A	標準型	13 mm	0.5 – 15 kW	75 mm
B	標準型	17 mm	2 – 55 kW	125 mm
C	標準型	22 mm	10 – 150 kW	200 mm
D	標準型	32 mm	40 – 500 kW	355 mm
SPZ	窄型	9.7 mm	0.5 – 8 kW	63 mm
SPA	窄型	12.7 mm	1.5 – 30 kW	90 mm
SPB	窄型	16.3 mm	5 – 80 kW	140 mm
SPC	窄型	22 mm	20 – 250 kW	224 mm

提示： 窄型 V 帶（SPZ、SPA、SPB、SPC）每條皮帶的功率容量比傳統截面高 30–50%，建議用於新設計。